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 Tracking in the Near North Winter Landscape
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Tracking in the Near North Winter Landscape

I was excited the weekend of December 14-15, 2024,  to host Earthtrack’s Tracking Apprenticeship group out of our home in Nobel, just North of Parry Sound.  My hope was to share the diversity and abundance of wildlife of this part of the “near north” with the group, most of whom were from Southern Ontario.

Two weeks before the scheduled weekend we did not have a flake of snow on the ground and I was a little concerned.   Three days later though, on December 4, bam!  Winter arrived and we had 2-3 feet of snow and were so thankful for it.

On Saturday we headed forty minutes north of town to crown land near the Naiscoot River.  Sunday, we stayed closer to town, exploring the forest and wetlands near Avro Arrow Road.

Over the two days we observed the tracks of seventeen different species including:

ruffed grouse, raven, northern flying squirrel, pine marten, fisher, moose, white-tailed deer, shrew, vole, wolf, red squirrel, red fox, white-tailed deer, river otter, short-tailed weasel, northern racoon and beaver.

We spent most of the weekend following fisher trails.  I was astonished by how active they are and how they weave back and forth and over and under and around trees and other landscape features.  At Naiscoot, we began following one fisher trail (presumably a female), but before long encountered a second trail that was much larger and in which we could really see claws in the drag marks.   While the trails did not obviously follow on top of each other, we did observe places where they crossed or were in close proximity.  

Early in the day we observed some ravens taking off from the forest.  This lead us to two different sites where a fisher had fed- one on a red squirrel, and the hind leg of a deer.

 

We wondered where the leg came from?  Road kill, predation?  Did the fisher bury it or did they dig up the cache of the original predator?  The meat had been cleaned from most of the bone, but there were not really any clear teeth marks on the bone.

It was so interesting to see how the gait of the fishers changed depending on snow depth and the purpose of travelling, for example a two by two lope in deeper snow, transverse lope in shallower snow, walk or trot when near to food sources.

 

 

One fisher print also reminded me of a time when I once confused a print of a fisher with what I had thought was a bobcat.  One missing digit can sure make a difference, and every pad does not always register!

 

 

 

 

 

 

 

 

 

I was also thankful to have the opportunity to observe and compare the off-set lope of a short-tailed weasel (on the left side of the picture), side by side with the bound of a red squirrel.

 

Finding a pair of wolf trails was also a treat.

 

At Avro Arrow, I had my first opportunity ever to track a pine marten.  There were some areas where the marten and fisher shared the same trail, giving us the opportunity to compare their prints side by side.  While they both moved in a two by two lope, the marten prints (pair two and four on this picture) were smaller with a more narrow trail width.

 

We also observed the sitz mark of a northern flying squirrel who had glided down from the trees and then landed leaving a tail drag across the snow before bounding away.

 

An additional treat was the trails of at least one (or more), river otters.  It was easy to imagine how they enjoyed travelling on their bellies as they slid across the landscape, whether it was over ice, snow, rocks or other natural features.  At one point, one even slid over the snowshoe trail we had left in the morning!

One of the best parts of this weekend for me was how emergent it was.  While we had a general idea of where we might end up but at both locations we let the tracks lead us.  We followed one species, and then the next as the tracks presented themselves.

I was struck many times, by how the land, when covered with new snow, is like a giant canvas.  The animals were the artists, leaving their unique tracks, signs and prints as they went about the business of surviving life in the winter forest.  How magical it was to spend time in this magnificent gallery with like-minded folks. 

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 A Story Of Stones At Old Baldy
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A Story Of Stones At Old Baldy

Bend over.
More.
Even more.
You may have to
sit
on the ground
with your head
almost
touching
the earth.
You have to look
a rock
right
in the eye.

– from Everyone Needs a Rock by Byrd Baylor

I will do my best to keep this one concise, but covering 4 Ga (four billion years) in a short blog post is going to be a tough one, so please bear with me.

An Introduction

The Beaver Valley was shorn into the land through the cataclysmic pummeling of boulders and rocks propelled by massive riverine torrents spilling from the melting glaciers. Smashing their way across the newly exposed landscape which had been buried under approximately 2 km (~1.25 miles) tall walls of glacial ice, massive boulders, some carried by the ice from thousands of miles away, were being unloaded by the retreating glaciers and hurled across the landscape by epic rivers of incredibly cold meltwaters. These boulders bounced and slammed against the Georgian Bay Shale, and Manitoulin and Amabel Dolostone formations and a few other layers of bedrock before being washed out to the bottom of Georgian Bay, or settling along the valley floor. A broad river, much larger and much more fierce than the present day Beaver River, ran from valley wall to valley wall, eroding rock and depositing till picked up as the glacier repeatedly grew and lurched Southwards and ebbed and waned back Northwards over 2.5 million years of various states of glaciation. This till, carried from as far South as the Appalachian Mountain ranges to the Precambrian volcanic rock of the far North of Turtle Island, was strewn about the valley floor. The area looked like many modern mountain glacial moraines found today, full of rubble and stone, gravel and sands, with no visible life to be seen.

In time, and I mean a long time, wind blown spores of lichens and fungi along with seeds of cold hardy grasses and forbs began to colonize the rubble slowly changing the landscape from stoney valley to something akin to the present day tundra. Seeds of shrubs like willows (Salix spp.) and cottonwoods (Populus spp.) may have been first if we look to the tundra for example, growing quickly and dying back, building up a soil layer more suitable for later post-glacial successi0nal species. A couple of those species were White Pines (Pinus strobus) and Eastern Hemlock (Tsuga candensis) both lightweight wind blown tree species hailing from glacial refugium in Southern Appalachia. Maples (Acer spp.) migrated up from the mouth of the Mississippi, yet took a bit longer than the lighter and hardier conifers. As the world warmed and more faunal visitors returned to the valley, larger seeds were spread. Animals like American Crows (Corvus brachyrhynchos) and Blue Jays (Cyanocitta cristata) would be great acorn and chestnut dispersers, spreading the heavier seeds with their scatter hoarding caching behaviours. I have no records or research, but I bet the Huron-Wendat people who occupied the lands of the Beaver River, and those who likely were there before them, also had a big role in whatever diverse plant species began to spread through the valley. Slowly, very slowly the valley would be transformed into the deep lush forests whose soils and possible seedbank so eagerly desire to reclaim the land if let be.

How Can We Know What Has Happened On The Land By Looking At What Remains?

Dolostone

Marcus sitting with the dolostone.

An image of what Turtle Island/North America looked like 450 mya.

The photo above is of Marcus sitting against the sheer rock face at the top of Old Baldy. The stone is exposed dolostone which makes up Amabel Dolostone Formation. This dolostone is the product of the bodies of ancient animals which dwelt within the tropical Silurian sea about 450 million years ago.

Wait.. what?

Let me explain.

Dolostone is a sedimentary rock, formed from the calcium carbonate stored in the shells of some ancient brachiopods and cephalopods as well as from the carbonate-secreting algae which lived in a shallow tropical sea some 450 million years ago (mya). At this time our region of Turtle Island/North America was just below the equator and this gave lots of opportunity for ancient sea animals to flourish in the warm waters. The bodies of these animals were made up of the calcium carbonate mentioned above. These bodies which absorbed and used the calcium carbonate to create their hard shells eventually died and sunk to the bottom of the sea. Time rolls on and more and more bodies piled up. More carbonate was released into the aquatic environment Though time and pressure of oceans, through currents and more and more bodies piling up, limestone began to form. As the limestone begins to form a process of dolomitization occurs with the limestone becoming interspersed with magnesium found in the sea water. As the limestone becomes impregnated with the magnesium and the whole solution hardens, it all turns to dolostone.
This dolostone is very similar to limestone, yet with the addition of the magnesium, becomes very durable and is therefore less prone to erosion. While other layers of rock and shale may wash away after 400 million years, the dolostone remains as a remnant sign of the ancient sea beds. As near my home in Guelph, the dolostone cliffs of Old Baldy are like the fossilized dinosaur tracks through ancient creek beds in Texas – remnant traces of life from long long ago.

Glacial Erratics

Throughout the forests of Old Baldy there are many large boulders which do not conform to the dolostone bedrock which underlies everything. They just don’t match up with the rest of the rock that makes up the hill. If the hill is covered in rocks that don’t look like, or aren’t made up of the same stuff as the rest of the hill then we can understand, in tracking terminology, that these boulders are not part of the baseline of the landscape. We can then ask the questions, where are they from and how did they get there?

Some folks used to think that these massive rocks came from the great biblical floods of Noah. Wave action rocked the rocks back and forth for a while until the rocks ended up many thousands of kilometers from where they originated. In a distant sort of way they were right, but instead of water, it was ice.

The most recent glacial advance began about 95,000 years ago and during that period massive lobes of ice advanced Southwards across Turtle Island/North American swallowing and consuming almost everything in their path. As the glaciers covered the landscape, blocks of rock were torn off their home landscapes and carried by the glaciers only to be deposited someplace new. These rocks are called glacial erratics as they are wanderers (errare means ‘wander’ in Latin) across the land. They’re picked up, tossed around and left behind like I do with small sticks and stones on my own wanders. Now the cool thing about these erratics to a tracker might be that if geologists can figure out where the rocks have come from, then they can use these rocks to reconstruct and understand the path that the glaciers took.

I am still new to rock identification and when Alexis and I spoke about the boulder in the photo above, we both knew who to ask for more information: Bill the Bear, retired hydrogeologist and always curious and friendly tracker. I ended up writing him an email and asking what he could tell from looking at a photo of the rock. Turns out he could see a lot.

First he could tell by the colour and texture of the rock that it was likely volcanic in origin and because of that “very very far from ‘home’ ”. He wrote that it was likely composed of iron and magnesium that have been altered by chlorite on the rocks surface as result of being exposed to water over millions and millions of years. He suggested that if his assumptions were correct, then this erratic was likely of Precambrian origin. This would have been “part of the ‘mountain-building’ process, in what is now northern Ontario, which made the Himalayan mountains look like foothills!”
Bill mentioned Precambrian in origin which I think implies that this rock is from the Canadian Shield which is Precambrian igneous rock, which means it was formed between 3.1 Ga (3.1 billion) to the beginning of the Cambrian Period, about 538.8 million years ago. This is a massive span of time, inconceivable to me really, but somehow still awe inspiring. The word igneous means that this rock was “born of fire” or as Bill mentioned, volcanic in origin.
Rocks of volcanic origin are produced in a variety different ways. In the book Ontario Rocks by Nick Eyles, the author states that igneous rocks are formed when magma cools and becomes solid. The grain size of the the rock depends on how fast the rocks cool, with finer grains showing up in rocks that have cooled quickly and course grain in magma that has cooled slowly. This rock was rough to the touch and in my follow up research gets me thinking of a type of rock known as gabbro which is a slow cooling rock formed from molten magma from deep within the Earth’s crust. I have read that these rocks would have become solid more 1 Ga (1,000,000,000, one billion) years ago, and was eventually brought to the Earths’ surface by uplift caused by tectonic shifts and erosion caused by weather, water and wear on the land. Then again the glaciers picked it up and plopped it down at Old Baldy perhaps around 12,000 years ago.

I havn’t been able to figure out more about this rock in particular but I am in search of anything more that might flesh out the details a little more. This might take some time, but I guess that’s what this is all about. The rocks will wait.

Post Glacial Isostatic Adjustment

As mentioned above, the ice sheets around the area of Old Baldy was covered in these massive mounds ice approximately 2km thick. 2000m. 4 CN Towers. 11 Seattle Space Needles. They were @#&$*+!! huge! It’s hard to imagine how tall they must have been, let alone how much they weighed. But they weighed a lot. According to one source, a cubic meter of ice weighs about 916 kilograms (2020 pounds), so it’s kind of interesting to think of what 2000 m of ice might weigh, but really that’s just one spot. Imagine these ice sheets covering all of the Northern parts of Turtle Island/North America and almost the entirety of Canada. To quote Wallace Shawn’s character Vizzini in the 1987 hit The Princess Bride, “Inconceivable!” I can’t find actual numbers but lots of adjectives are thrown around, such as “enormous,” or “massive,” and “incalculable” are a couple of good ones. The glaciers weighed so much that they depressed the Earth’s crust and mantle below. In Northern Ontario near Hudson’s Bay there are estimates that the land was pushed down about 270-280 m (~300 yards), though less in Southern Ontario. This made the land adjacent to these depressions rise as well, like a crest or plate when considering pressure releases in animal tracking.

The rate of rebound in the area around Old Baldy in Southern Ontario would be about 4 mm per year. Image from Crustal motion and deformation monitoring of the Canadian landmass by Joseph A. Henton, Michael R. Craymer, Rémi Ferland, Herb Dragert, Stéphane Mazzotti, Donald L. Forbes. Geomatica, 2006.

But something amazing happened as the glaciers started to retreat. The land which had been previously depressed by the incredible weight began to rebound and rise up, and much the adjacent lands which had lifted began to subside (sink down again). This process of rebounding land is called Post-Glacial Isostatic Adjustment. Though it has had many other names over the years such as glacial rebounding, isostatic rebound or crustal rebound, post-glacial isostatic adjustment makes the most sense in that the land isn’t just lifting up again. Some land is subsiding (sinking), some land is being pushed away from where it once was, and this is causing changing sea levels, and even shifting the Earth’s rotation. Post-glacial isostatic adjustment translates to “Changes in equilibrium of the Earth’s crust after the glaciers” which is a more honest and accurate interpretation of what the names are trying to describe. To get back to the point, through these changes of the elevation of the land in the Old Baldy/Blue Mountains area, the land in that area has risen over 15 m since glaciation and is still continuing to rise at a rate of about 15 cm per hundred years or 1.5 cm per decade. It’s not that much in the grand scheme of things, but I still think it’s pretty wild.

When researching geology in the context of tracking the landscape I am reminded of a phrase that Alexis Burnett often attributes to one of his teachers Tom Brown Jr., and I hope I am not misquoting here.. “The Earth longs to be flat, everything else is a track.” A mountain is the track of tectonic plates shifting and smashing into one another, an odd stone in a field the sign of a glacier, and an Oak (Quercus sp.) tree is the remnant sign of a seed possibly dropped by a Blue Jay many years before.
I’ve been thinking about how in a world of calamity and upheaval, extinction and war, that sometimes there is a grounding in remembering the ancient body that we all come from.

Researching and working towards a deeper understanding of the geology of this venerated hill has actually been a peaceful reflection when places of peace have been so hard to find. I recognize that these are epic cataclysmic histories, but the stories held in the stones at Old Baldy have brought about a deep sense of peace for me when it seems so lacking in the world right now. Maybe it’s the disconnect of me not being present for the upheaval and torrent of glacial meltwaters and crushing sheets of ice, but doing the research, piecing together clues, and imagining the magnitude does create a profound sense of wonder and awe, a stupefying amazement in the unveiling of a billion years of mystery written on the body of the hill. I deeply appreciate the work and practice of listening to the stones and tracking the beauty of the land.

To learn more :
Walking Through Time : Exploring Niagara Escarpment Geology in the Beaver Valley Bruce Trail Section by Beth Gilhespy, M.Sc. Self published, 2023.
After The Ice Age : The Return of Life to Glaciated North America by E. C. Pielou. The University of Chicago Press, 1991.
Ontario Rocks by Nick Eyles. Fitzhenry & Whiteside, 2002.
Geology and Landuse Between Guelph and Hamilton: A Self-guided Tour by Chesworth, W., Martini, P., McCarthy, P. and Sadura, S. Dept. Land Resource Science, University of Guelph, 1996.
Ancient Earth interactive globe – see what the Earth looked like from 750,000,000 years ago up to now
NASA’s video on Earth Rebound and Subsidence
Ontario: The Geology of Isostatic Rebound – Rising Land

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 Mudflats are For the Birds!
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Mudflats are For the Birds!

On our most recent Apprenticeship Weekend, October 26-27, 2024, we spent seven hours tracking along an expanse of mud where the level of the Grand River had been lowered to accommodate spring runoff.  During that time we probably covered only a few kilometres, but each of us crossed paths with hundreds, if not thousands, of prints, most of which came from birds.

 

I’d like to go through some of the bird species we encountered, their distinguishing features and in some cases, associated behaviours.  I’ll go from the largest to the smallest.  My main source of information was the book Bird Tracks by Jonathan Poppele, published by Adventure Quick Guides.  Additional information came from Bird Tracks and Sign by Mark Elbroch and Eleanor Marks, Stackpole Books.

 

 

 

 

The largest print we observed was of a great blue heron, which its longest point, was 8” long.  The length of the print confirmed it was a blueheron as other large birds who would also be likely in the area (for example sandhill crane), have prints that are much shorter since they lack the long toe one (the hallux in birds).  The only species who might overlap in configuration and length is the bald eagle.  While we did see an eagle, we did not locate their prints, which are much more bulbous with talons registering further from the print due to their length and curvature.

 

 

 

 

 

 

 

 

 

 

Canada goose prints were abundant on the mudflats.  The tracks that interested me most were prints where there was a lot of weight on the toes, long strides and then an abrupt end to the line of tracks. The goose was running and then took off!  The prints looked so unusual as they showed striations or lines from the leading edge of the webbing.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Interestingly, only a few hundred metres from the goose take off, Tamara spotted another take- off point, this time from a crow.  Crows, ravens and bluejays, like all corvids “share a distinctive track feature: toe three angles to the inside and hugs toe two”( Poppele).  The crow, being much lighter and more agile than the goose, was able to take off from a standstill with a big push down as evidenced by the two prints beside each other, pushed deeply into the mud.

 

 

 

 

 

 

 

 

 

Another track that we observed many times was of the greater yellowlegs.  This is not a common shorebird normally, but was likely in the area on their migration.  A few of us were fortunate to have been close to one individual as they walked along the shore probing the mud.  Through my binoculars the legs were indeed a very bright yellow.  The yellowlegs prints could be distinguished from other shore birds because of their size,  slender toes and lack of palm showing in the print. 

 

 

 

 

 

 

Photo credit: Byron

 

Next in order from biggest to smallest were prints of  killdeer.  These prints were more abundant than the yellowlegs and could be distinguished because they were almost equal in length and width, were asymmetrical, tended to be pigeon-toed in their movement and lacked a hallux.  We observed several killdeer both flying and walking.  Like the yellowlegs, they were likely not resident, but rather were on their migration journey.  Photo credits: Byron

 

 

The final shorebird print we observed was of a sandpiper (likely spotted).  This print was smaller still and less abundant than the other shorebirds.  Note- this image was taken from a different location

 

 

 

 

 

As we observed these prints and many more (including red fox, opossum, beaver, mink, racoon, skunk, white-tailed deer, muskrat), I was thankful for mud, clay, clear skies, knowledgeable mentors and friends who enjoy connecting to animals through their tracks as much as I do.  Looking forward to our next adventure together!!

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 Tracking at Saugeen Shores, 2024.09.28
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Tracking at Saugeen Shores, 2024.09.28

The most recent outing with the Earth Tracks tracking apprenticeship group was too much. I can’t even figure out what to start writing about. Maybe it should be about the Northern Harriers (Circus hudsonius) we saw swooping low over the grasses and sedges out along the peninsula? Or maybe the Sandhill Cranes (Antigone canadensis) and Great Blue Heron (Ardea herodias) wading out across the small inlet. I think I’ll start with the confusing ones…

When the apprenticeship visited the Saugeen Shores, I got confused. How do we tell the difference between Sandhill Crane tracks and Wild Turkey (Meleagris gallopavo) tracks? I am sure it is simple to some folks, but I still get mixed up every time I encounter either of their tracks where species could overlap in the same habitat.

Let’s start with my quick measurements. I sadly only wrote down one length measurement and that was 8 cm. The widths I wrote down were 9.5, 11.5 and 12 cm. While the length measurement does not fit for either Wild Turkey and the Sandhill Crane according to Elbroch and Marks, the widths do. Some of the tracks I thought I could make out a hallux, or toe 1, but I wasn’t sure as there were many of the same track in the area, often overlapping one another.

All in all, Sandhill Crane didn’t seem as likely creators in light of all the other factors mentioned above. Instead I believe the tracks were made by a mixed group of older and younger (considering length of some of the tracks) Wild Turkeys.

These weren’t the only bird tracks we saw…

Edited photo of Greater Yellowlegs we saw taken through my monocular (photo edited for better display online).

I first noticed the Greater Yellowlegs (Tringa melanoleuca) calls before seeing them. They reminded me of a Killdeer (Charadrius vociferus) call in timbre and frenetic energy, but different in cadence and length. We were on the beach where I had just been looking at Killdeer tracks moments before and wondered if it was them, but when they were pointed out later it made more sense that these were the Greater Yellowlegs based on their size. When I got out the monocular my eye was attracted to their long bill and airfoil-ish, football-like, body shape.

Andy and I watched two of the Yellowlegs run and stutter about in the shallow water of a narrow shallow channel running between estuaries at the edge of Lake Huron. We waited until they had made their way around a small sand bar and when they did we went over to where they had just been in search of tracks.

Greater Yellowlegs tracks are similar to Spotted Sandpiper tracks, which come in at small 2.2 – 2.5 cm (⅞ – 1 in) L by 2.5 – 3.2 cm (1 – 1¼ in) W, which is a noticeably smaller. Jonathan Poppele says the same as Elbroch and Marks, that the metatarsal will rarely show on the Yellowlegs, but does tend to show up on the Spotted Sandpiper. Good to keep these in mind in case I see either of these two in the future.

The Yellowlegs tracks kept us busy for a while, but we kept going as we had so much more to explore. I walked back to grab my bag and revisit something else I had taken a look at earlier. Some skeletal remains of some sort of fish. A couple of the bones we found looked like they could be a spinal column. A couple looked like saw blades and we even cut some sedges with them, just to see how well they would cut. Some I couldn’t figure out at all. And then there were a couple which struck me both as familiar and as very strange. Two identical bones, the same bone yet likely situated opposite each other in the body, curved with small tooth-like tubercles or nodules on them. Here are some photos, one from the day of, and some taken later in my backyard.

Gill filaments and gill rakers on a Rainbow Trout (Oncorhynchus mykiss).

Most fish have gills. Some have lungs, but we’re going to discuss the gills so I am going to stay on point. How do gills work? Well the fish draw in oxygenated water in through their mouth. They then pump this water over the gill filaments so oxygen can enter the bloodstream. These same gill filaments also allow oxygen poor water to leave through the same gill slit.
Most bony fish have five boney gill arches, sometimes called branchial arches, on each side of their heads. The gill arches support the gill rakers on the anterior side (closer to the front of the fish) and gill filaments on the posterior part (closer to the tail). Gill filaments again are where gas exchange occurs. The gill rakers are little protrusions which “rake up” small particulate which can be consumed by the fish and may also be for prey retention in the case of a fish consuming smaller stuff. Think of them both as filters, one for gas, the other for food.

1,1,3-3,1,1 dental formula of the European Carp, counting from the outside in on the near gill arch, and then the inside out on the far gill arch.

For some fish, the fifth gill arch is modified. There are no gill filaments. Instead there are boney tubercles are called pharyngeal teeth. These pharangyal teeth are probably modified gill rakers which have evolved to serve a new function. They sit in the back of the throat of a few different fish species. They aren’t teeth anatomically, but they serve a lot of the same function as teeth do. They help fish to crush and break down small mollusks and crustaceans or even tough vegetation that they are consuming as well as help to filter whatever is going down their throats. Based on the size of the teeth and the other bones we found, I think we identified this individual as a carp.

Carps are in the family Cyprinidae which also include chub, dace, shiners, true minnows, koi, and Goldfish (Carassius auratus). They all lack oral teeth but they do have pharyngeal teeth (as do some other families as well), and these pharyngeal teeth display with such diversity that they can be used to identify different species. There are even pharyngeal teeth formula to help with this identification, but for now I only know the this individual species dental formula : 1, 1, 3 : 3, 1, 1, counting from the outside in on the near gill arch, and then the inside out on the far gill arch. Based on the teeth we found, I am going to call this fish a European Carp (Cyprinus carpio), also known as the Common Carp. They are a non-native species which loves the warmer vegetated shallows of the Great Lakes and many of the rivers which spill into them, such as the Eramosa River where I live. European Carp teeth have been described as having the same 1, 1, 3:3, 1,1 dental formula, and the teeth themselves are “robust, molar-like with crown flattened or somewhat furrowed”. Still no idea how they died and wash up on the beach, but they were there, picked clean, likely by some of the birds in the area as few bones which were present were broken, which is pretty common sign for mammals scavenging.

The thin drag marks left by the outer edges of the tail projections (called uropods) are usually an obvious distinguishing feature of crayfish (Astacoidea) trails. Trails appear as two well-spaced parallel lines, with tracks from the legs registering outside these lines. Crayfish walk primarily on the four pairs of legs (periopods 2 through 5) behind their claws (periopod 1), the first two of which have two fingers at the end that form small pincers. Tracks often register in groups of three or four, depending on whether the last pair of legs leaves distinguishable imprints… On good substrates, the pincers on each of the front two leg pairs register as two distinct dots.

Looks right, sounds right, but I wish I could know the direction of travel. From looking at the drag marks in the dots, again created by the legs, I believe that the crayfish was heading from the top of the image towards the bottom of the image. Why do I think this? Remember snow? Well, when say a White-tailed Deer (Odocoileus virginianus) or a Coyote (Canis latrans) is moving through the snow I often see a slope descending from where the animal is moving forward and about to put their foot down, and then a sharp lift out of the deep snow with incredibly little to no ascending slope at all. While this sand was not deep snow, I believe the same results happen in various substrates, even with different types of bodies creating the marks.

Another cool invertebrate trail we found looked muddy and as if little bits of sand had been pushed up from below to form a crumbling esker, like a tiny mole tunnel. We were looking at it wondering who could have made it when I remembered Shane Hawkins saying she once found a spot where a Common Snapping Turtle (Chelydra serpentina) trail suddenly ended in a strange muddle oval-circle shape. She wondered if the turtle had dug themselves in so she started to dig, and to her amazement, she found the resting turtle deep in the mud. I knew this wasn’t a turtle trail but decided it would be worthwhile to try and dig throughout a neighbouring tunnel and see if I could find something living inside it. And I did!
I dug out a small, maybe 22 mm long, wet, soft, squishy larvae which immediately reminded me of a firefly larva with it’s strange somewhat segmented abdominal terga plates, extending and retracting head. Firefly are in the Coleoptera order (beetles) and this little dude looked a lot like a beetle larva so that was my first guess. It isn’t a very useful guess though. Coleoptera make up about 40% of all known insect species, and about 25% of animal life on Earth. To put it another way, 1 of every 4 species of animal on Earth is a beetle. So it could be a beetle or it could be an larva that looks somewhat similar.

It is likely that the species we found is in the genus Stratiomys. I ended up posting the photo above on inaturalist with the suggestion of Stratiomys as the genera and another user confirmed the i.d. I then looked up the user and it turns out he works as a taxonomist with a special interest in Stratiomyidae! Inaturalist is a very useful resource. I would suggest looking using the website/app, especially for difficult i.d.’s like insect larva.

We kept on with our day, meaning we walked another 10 meters or so and then stopped again to admire another trail.

The trail could be described as alternating patterns of two rows of dots laid atop one another. We interpreted this as a front foot landing and then a hind foot. But which was which? And which way was the animal going? And who was this animal?

When I see a trail like this, a trail that does not widen or narrow along the entirety of the length we can see, as I did with the crayfish, I immediately think of a body that has a fixed width, or at least has parts of the body that cannot get any narrower or wider regardless of how fast or slow they are going. Alastair measured the trail width at about 20 cm (~8 in). This is wider than any invertebrate that I know of and must denote another, larger species. I think we all understood almost right away that this was a trail left by a turtle. Their spines cannot flex and they cannot narrow or widen their trail widths. But which turtle was it? There are records of Common Snapping Turtles, Midland Painted Turtles (Chrysemys picta ssp. marginata), Spotted Turtles (Clemmys guttata), Wood Turtles (Glyptemys insculpta), and there may be Blanding’s Turtles (Emydoidea blandingii) and maybe Northern Map Turtles (Graptemys geographica) in the area. All of these turtles but one are too small to make such wide of a trail. The Midland Painted Turtles trail widths according to Filip Tkaczyk in his book Tracks and Sign of Reptiles and Amphibians are 10.16 – 16.76 cm (4 – 6.6 in), which is too small for the trail we found. The Common Snapping Turtle trail width is 20.32 – 26.67 cm (8 – 10.5 in) which fits well for our trail we found. I do not have the numbers for the trail widths on any of the other species listed above, but I am fairly certain that the Snapper is the largest turtle in the area, so the trail is likely from a Snapping Turtle. I don’t remember if there was a tail drag or not, but the presence of a tail drag can help with the identification, as well as the plastron drag. The plastron is the bottom part of the turtles shell on the underside of the turtle. Some turtles drag their plastrons, while others tend to lift theirs off of the ground when they walk. Painted Turtles have a relatively wide plastron that often drags when they walk, where as the Snapping Turtle raises their body as they walk and the plastron does not show until moving through deeper substrates or when coming to a stop. Again as we saw no evidence of a plastron drag this too points to a Snapping Turtle.

Now, more questions. What was the direction of travel, towards or away from the water, and how do we know?

Snapping Turtles have 5 toes on the front feet and all of them tend to show up in ideal substrates. They also have some big long and thick claws which really dig into the sand or mud or other substrates you find them in. Front tracks also tend to be turned toward the center of the animal/trail at about a 45° angle, which makes it easier, sometimes, to figure out fronts from hinds. The hind tracks also have 5 toes, but usually only 4 of the toes register. The hind tracks do not turn inward in that same 45° angle as the fronts do, but instead face forward towards the direction of travel.

Alastair took the time to describe the trail in detail for all of us noting exactly this, that the front foot claws were angled towards the center of the trail, and that the rear foot would be pointing in the direction of travel, which meant the Snapping Turtle was walking up and out of the water towards the higher vegetated ground.

We sat down for lunch around the spot of the Snapping Turtle and watched a Ring-billed Gull (Larus delawarensis) make some tracks as we ate and then moved on.

I have to admit that we saw a lot more stuff, fascinating discoveries, each one deserving their own lengthy blogpost but I look at my calender and see that with another tracking weekend coming up in only a few short days, I feel like this one needs to be brought to a close. Perhaps someday I’ll get back to some of the other things we saw but for now this is the end.

Now I just can’t wait to get back to Saugeen to see what new we’ll find next time.

p.s. Did you know that you can estimate the age of a fish from counting the growth rings on their scales? Similar to trees in cooler climates, fish grow slower in the winter and the growth rings show up closer together and create the appearance of a thicker or darker ring. These thick or dark “winter rings” can be counted to determine a fish’s age! Now I have to start looking at scales as well as teeth.

To learn more :
Bird Tracks and Sign by Mark Elbroch and Eleanor Marks. Stackpole Books, 2001.
Bird Tracks by Jonathan Poppele. Adventure Publications, 2023.
Freshwater Fishes of Ontario by Erling Holm, Mary E. Burridge, and Dr. Nicolas E. Mandrak. ROM, 2010.
Pharyngeal Teeth video by Timothy Spier
FishBase entry on Cyprinus carpio
Tracks and Sign of Insects and Other Invertebrates by Charley Eiseman and Noah Charney. Stackpole Books, 2010.
Tracks and Sign of Reptiles and Amphibians by Filip Tkaczyk. Stackpole Books, 2015.
A Guide to Common Freshwater Invertebrates of North America by J. Reese Voshell, Jr. The McDonald & Woodward Publishing Company, 2002.

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Wolf Spiders at Sauble Beach, September, 2024

On the weekend of September 28-29,  this year’s tracking apprenticeship group spent two days in the Sauble Beach area.  On the 28th, the majority of our time was spent along the lake shore where we were able to observe a variety of prints in sand, mud and silt that was either wet or in the process of becoming dry.

On the 29th, we moved inland away from the lake where there was much less moisture.  The dew from the night before, while no longer visible as drops, had dampened the sand enough that in the morning when we arrived many prints were very clear, telling the story of coyote, fox, squirrels, mice and other residents who had been active during the preceding evening or early morning. 

 

 

These squirrel prints were very clear in the dew-dampened sand

 

 

 

 

 

 

 

 

 

 

The sand allowed us to clearly see the recent movement of a fox as they went back and forth across the area.  We were able to compare fox and coyote tracks and analyze gaits and some movements.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

The sand also beautifully held onto tracks and trails of smaller creatures including insects, spiders and snakes.  It was these that caught my attention as they were so different from the prints of mammals, and are rarely seen in my neck of the woods where I don’t often see fine-grained sand.

The first new sign that caught my attention was these. 

 

 

Once the first was noticed, we spotted several more.  According to Tracks and Sign of Insects and Invertebrates by Eiseman and Charney, this hole and it’s accompanying tube are likely the den of a “wolf” spider.

As a little girl, “wolf spiders”,  like “fire ants” to the children I spend time with today, were sort of mythical.  Any spider that was big and hairy we called a “wolf spider”, but I have never had the opportunity to learn more about them until now.

Wolf spiders belong to the genus lycosidae (almost 2500 species known worldwide),  and are known for having keen eyesight (and eyeshine when put under a light at night) and are both hunters and opportunists.  They do not use webs to trap their food, and will hunt both in the day and at night.  Females of this genus carry their egg sacs in their spinnerets, occasionally putting them down when hunting.  Once the eggs hatch, the mothers carry them on their back or bellies until they disperse.

Three distinguishing factors that help identify wolf spiders from other spiders are the placement of their eight eyes, presence of tarsal claws, and the angle at which they carry their fangs (chelicrae) (pointing towards each other).

 

 

While wolf spiders can be found in leaf litter, under rocks and even in sphagnum moss, some species, like the ones in the sand in Sauble, build a burrow.  According to Eisemen and Charney, “Many wolf spiders make silk-lined burrows in the ground with circular entrances.  When excavating, they tie the soil together in little pellets which they carry in their chelicrae and drop a short distance from the burrow entrance.”  Some species also create a “turret”, as we saw at Sauble.  These spiders will also block the entrance to their burrows for the winter.  Wolf spiders have also been known to carry their egg sacs up to the mouth of their burrows to sun them.

An additional sign that may be found around wolf spider burrows are their footprints as they make hunting forays as I believe can be found in the image above.

I look forward to learning more about wolf spiders and other invertebrates who leave their trails and sign in the sand in the future.

 

 

 

  

 

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Snapping Turtle Nests and the Joy of Wondering

  

Over the weekend of September August 31-September 1,  a small group of four of us joined Alexis for another weekend of tracking as part of the 2024-2025 Tracking Apprenticeship program. This particular weekend we were based out of the Algonquin Wildlife Research Station.

The weather was perfect for tracking; sunny, but cool and breezy for most of the weekend.

On both days we spent most of our time on the far side of Lake Sasajewun.  Even though we were in Algonquin on a long weekend, we did not see another soul while on the land together, but we did see lots of tracks and sign.  Of note were  prints, scat or other sign of the following species: 

southern flying squirrel, moose, otter, white-tailed deer, mink, muskrat, pine marten and black bear.

Of particular interest to me was our discovery of a lone snapping turtle egg.  My part of the province, Georgian Bay/Muskoka, is home to many turtles.  I have seen eggs laid in many different locations, but our discovery of a lone turtle egg, in the “cradle” of a large tree tip up, was most unusual and led me to decide to write this blog about snapping turtles.  The egg (see above) was in
a depression that was at least 1.5 m wide and 1 m deep.

Snapping turtles are the only species of reptile in Ontario whose eggs are spherical.  (The exception to this is the spiny soft-shelled turtle, but they are not found this far North.)

Before I had a chance to begin writing this post, a friend and I made another discovery closer to home that made for the great tracking experience that I now share.  This gave me a chance to apply previous knowledge, make use of print resources,  and exercise the skills of observation and questioning that I have learned from Alexis, Byron and Tamara since 2022. 

 

As I write, the date is September 7.  The temperature dropped last night and now it truly feels like Autumn, with today’s high being only +11 C, and it has been raining most of the day.  I went tracking this morning, and before we had even entered the
forest, we encountered a mystery.

.

Two snapping nests (by the size, shape and volume of eggs), had been very recently dug up by a predator.  The first question was who had dug them up.  To answer this question I needed to consider my best guesses of who would eat turtle eggs in my area: red fox, raccoon, skunk, coyote (the hole was too small for bear).   A single canine print led me to think fox or coyote.  The size of the print was too small for a coyote.  Further evidence that the predator was a fox was the scat that I discovered in the exposed nest cavity.  I had not observed this behavior, (the depositing of scat into a food source) before. We had to wonder whether it might have been a sign that could be interpreted as “This is my food, keep out!).  The hole and nearby vegetation did
smell like fox urine.

I wondered, could there be any eggs left in the hole that the foxed missed/planned to get later?  Was that the reason he/she had defecated right into the hole?   After carefully removing the scat, we started to dig and removed many empty shells until finally discovering two that were partially hatched, and one that was still unopened.  One of the hatchlings appeared dead while the other moved slightly.

Once the hatchlings warmed up in the closed car (as we went tracking for an hour in the forest), we were able to safely release them.  It felt good to know that we had helped two make it to the relative safety of the wetland from which their mother had emerged in the spring,

.

As we pulled out onto the road (an on-ramp to highway 400 South) I noticed more hatchlings on the road.  We discovered four, one of whom was still alive.  There were also at least four additional fox scats on the road.  I guessed that the fox or perhaps more than one fox, had spent the last evening and early morning eating hatchlings.  With their keen ears and noses, they likely were able to easily find them as they moved through the grass, trying to find their way to water.

 

Due to time constraints, we didn’t examine any of the scats to see their contents.

 

Questions we were left to wonder:

-Did the fox find the hatchlings and then go back to the nests to dig them up or did the fox notice them emerging and then start to eat them?  (We found one hole that looked typical for a nest that had safely finished hatching.)

 

And finally, how did that egg end up below that tipped-up tree in Algonquin?  No visible nest in site, no tooth marks on the egg either.  This one will have to remain a mystery.

 

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 Invert Sign at Dunby Rd.
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Invert Sign at Dunby Rd.

Atop of a Common Milkweed (Asclepias syriaca) plant, on one of the highest leaves, we noticed a slight inward bend to the leaf, with a bit of webbing holding the opposite leaf edges closer together. When I leaned in to examine the leaf, a midsized spider emerged. They were hairy, striped and spotted. This spider had two darker lines going up the middle of her abdomen with white spots along them. I kept trying to reposition the leaf so I could get a photo of the spider’s face in hopes of counting the eyes and looking for the pedipalps (sensory appendages at the front of the spider) to see if this individual was a male or female. You can usually tell male or female based on the size of the pedipalps. I remember Chris Earley, naturalist at the University of Guelph Arboretum explaining once that the pedipalps on male spiders look like little boxing gloves held at the front of their faces, and I can really understand this image and helps to remember. This individual kept shifting their stance with every turn of the leaf under they eventually hopped down to the leaf before and I couldn’t see them anymore. Based on the hop, the size, and the way the spider held themselves, I guessed a jumping spider (Salticidae).

When I gave up on trying to find the spider who had hopped away I was gifted with another chance to examine a spider, as a second spider, slightly smaller than the first, emerged from the tangle of webbing at the base of the Milkweed leaf. This time the spider looked very different. This one appeared to be mostly black, with two white lines opposite each other in the middle of their abdomen. I also noticed two interesting red spots, or bands along the abdomen, and questioned, as I always do when I encounter any black spider with red colourations, if this was younger Northern Black Widow (Latrodectus variolus) before remembering that the Black Widows are much smoother, shinier spiders and through present, are rarely encountered in Southern Ontario. After a second, we could see that this black spider looked similar enough to the first, and I think a couple of us thought this too was a jumping spider. Soon this second spider jumped out of view. I examined the Milkweed a little longer and moved on.

It was only in my follow up research at home, checking the 2013 book Common Spiders of North American by Richard A Bradley that I learned that these two fairly distinct looking spiders were probably of the same species, the Brilliant Jumping Spider (Phidippus clarus), with the larger brownish one female, and the smaller black one, male. Brilliant Jumper is often found in old fields, open grassy areas, meadows, in all sorts of vegetation. This is exactly the habitat we found them in; a regenerating field, slowly being taken over by shrubs, some Scots and White Pine (Pinus sylvestris and P. strobus) and Trembling Aspen (Populus tremloides) . I really like thinking that if someone showed me a photo of a Brilliant Jumper I can then also imagine the habitat – the spider can be an associated sign of specific plant communities which would grow in these particular ecotones.

The silken construction, which was holding the folded in edges of the base of the Milkweed leaf is called a retreat. Many species of spiders create retreats and they are created for a variety of purposes including mating, protecting eggs, hibernating, resting, molting.. all really just hiding to avoid the detection of predators and/or waiting for prey to come by. Retreats can come in all sorts of shapes and forms, varying by species and may even show a great deal of diversity between retreats constructed by members of the same families. The retreats can be found the sides of human fabricated structures, or built on leaves, as the one above. Sometimes they are decorated with dead leaves, lichen, soil, and even body parts from the spiders dead prey. I know I’ll be looking for more Brilliant Jumper retreats now to see if I can sort out any common themes in their constructions.

As we slowly moved our way up a hill towards the woodland I stepped on a compacted pile of sand on the slope of the hill covered in grasses, Ragweed (Ambrosia artemisiifolia), Goldenrod (Solidago sp), and more. I looked down and saw that which I had just trampled, and just afterwards, I could smell them too.

These citronella ants are likely Lasius claviger, also known as the Common Citronella Ant or The Smaller Yellow Ant. Genus Lasius was formally known as the genera Acanthomyops. The “claviger” part of the name comes from “clavi”, which translates to “club” referencing their club-like antennae (“clavi” also informs the word “clover” to describe the common wildflowers in the Pea family). I have been known to eat a couple everytime I encounter them. I mentioned this to some of the folks present and a couple people tried tasting an ant. They are potently aromatic, with a citrusy, lemon verbena odour and taste which is quite pleasing. But I have never really known what causes this odour, and how the ants produce it. So I decided to look it up.

From my research, it seems like some members of the Lasius genus have enlarged mandibular gland located just inside the anterior portion of the head, which holds a lot of two very powerful citrus like compouds. One compound is citronellal, which is known to keep insects away in other contexts, which I wonder if aids in repelling would be parasites in the nest or wards off colonial invaders? Citronellal also acts as a antifungal agent, which would serve a species who mostly nest in soils, home to a myriad fungal hyphae. Citral another compound and is also found in some common plants such as Lemon Balm (Melissa officinalis), Lemon (Citrus limon), and Lemon Grass (Panicoideae subfamily). Citral is used in perfumery to enhance the lemony notes and also in flavouring of different foods.

Ants are very sensitive to chemical smells and pheromones and communicate extensively with these various compounds. I have read that the ants can share where food is by leaving a trail of scents excreted from their abdomen for other worker ants in the same colony to follow, while other chemicals can encourage ants to increase speed in their pace. In the case for Lasius ants, these powerful chemicals are likely being excreted as a chemical alarm call to alert other members of the nest when some alarm worthy event is happening, like when I stepped on the nest. Scents as alarm call is a pretty cool mechanism. I have been revisiting Eastern Chipmunk (Tamias striatus) alarm calls lately, such as their Chip! Chip! Chip! warning of ground predators, or their cluck, cluck, cluck warning of aerial predators. These auditory alarm calls alert us to the behaviours and movements of other animals on the landscape and is a form of tracking. Could we also then tune into our sense of smell as a powerful human tool to track our co-inhabitants? I believe we already do. We use scent to tell the difference between Coyote (Canis latrans), Fox (Vulpes vulpes), Porcupine (Erethizon dorsatum) and White-tailed Deer (Odocoileus virginiana) urine deposits. We can smell if a Striped Skunk (Mephitis mephitis) has sprayed recently. We can tell when fruits are ripe, or even the state of decomposition a body is in when we come across a dead animal on the land. Of course the citral and citronellal are a bit more subtle, but wouldn’t it be cool if we could smell the alarm given by the ants if a Common Shrew (Sorex cinereus) or Northern Flicker (Colaptes auratus) were to invade the ant nest? This is going in my list of tracking goals.

I still have an additional question about these compounds : how are these compounds produced in the mandibular glands? I still can’t sort that bit out. I am looking for the research, but my thought is that for researchers it is probably such a basic biological process that it doesn’t need to be covered in the literature. Maybe I’ll figure it out eventually.

We set off again, walking into the woods, exploring what we saw as we came to it. We checked out the scat of Ruffed Grouse (Bonasa umbellus) and Porcupine, a few different fungi and slime molds. Eventually as we were walking through to the tall mostly deciduous forest I got really stoked when I looked over and Diana was crouched down with some folks excitedly examining something on the forest floor. I had to figure out what they were all looking at.

A huge moth, a Silk Moth (Saturniidae family) to be a bit more accurate, was there nestled on top of the leaf litter just hanging out. Who were they? Were they resting? Hurt? It seemed like the moth was doing ok, but just chilling. I couldn’t identify the moth right away, but Diana did. Polyphemus Moth (Antheraea polyphemus). I took a closer look when I was photographing the moth (from a million different angles in case I missed anything) in hopes of learning to better i.d. a Polyphemus Moth in the future. The base colour of the moth is pale orangey brown, though sometimes can be pinkier, with transparent window (!!!) spots on both the forewings and hindwings. The windows on the hindwings are encircled by yellow, then black, and a touch of blue on the proximal side. I observed the antennae and realized that this was likely a female as the moth was larger and the antennae themselves were thinner and not as feathery or comb-like as males of many other moth species.

I was wondering if this female was going to be laying eggs soon, or if they had already? Polyphemus Moths, and all other Silk Moths actually, do not have mouths when they transform into adults, so perhaps this female was just tired from a short, but busy, adult life with no food and was just taking a rest on the forest floor. It won’t be a long rest though. The adults tend to only live for about four days. Turns out the Polyphemus females will emerge, quickly mate, lay tiny eggs that look like tiny chestnuts or maybe tiny hamburgers singly or paired, or even sometimes three together, and then die shortly afterwards. I read one page from the University of Waterloo where they observed a a Polyphemus moth lay 103 eggs in captivity between the dates of June 10-11 (1). I have read another website, this time the University of Michigan, where they write that a Polyphemus will only lay up to 5 eggs in a season (2). A blog (3)written by someone who raised a bunch of Polyphemus’ wrote that they can lay between 100 – 300 eggs. When I think to other insects and I get to wondering if the 103 number might be more accurate? Did UofMichigan mistake the number of eggs in a individual placement session? Maybe it varies with development of the caterpillar?

On the topic of different life stages of the Polyphemus, I wrote a short blog post on different Silk Moth cocoons, including the Polyphemus. Here is the entry on their cocoons :

Polyphemus Moth (Antheraea polyphemus)

Larval host plants : Ash, Birch, Cherry, Dogwood, Elm, Grape, Hickory, Maple, Oak, Pine, Rose, Willow.

Description of cocoon : Oval shaped, ~4.5 cm (1¾ in) usually spun with leaves in outer layer, though often found in the leaf litter. I have read and seen photographs of the cocoon dangling from a low branch similar to Promethea Moth cocoon. The silk is pale cream to white in colour until the caterpillar excretes a substance that toughens up the cocoon and changes the colour to a pale brown.

Notes : Woodlands and forests. Similar to Luna Moth (Actias luna) in size and shape though Polyphemus cocoon is thicker and more evenly oval and less squareish. Unlike other Saturniid moth cocoons, Polyphemus cocoon is entirely closed with no exit hole built in. Pupa will secrete an enzyme to help break down the cocoon when ready to emerge.

Now considering the Polyphemus and all I want to learn about them, I may try rearing them next year to see about observing and answering some of the remaining questions I have.

Learning more about invertebrates and the signs they leave behind is such a valuable part of wildlife tracking to me. I feel like when I teach or share about the inverts, most people are kind of “cool, but where are the mammals?” about it, but I hope to keep learning more so that I can inspire some deeper respect and awe about a couple whole other phylums (Arthropoda, Mullusca, Annelida, etc)! There is so much life out there, that doesn’t look like us, move like us, eat, excrete, breed or breathe like us and every time I learn something new I get stoked. I am grateful to get to share some of that excitement in this post.

To learn more :
Common Spiders of North American by Richard A Bradley. University of California Press, 2013.
Tracks and Sign of Insects and Other Invertebrates by Charley Eiseman and Noah Charney. Stackpole Books, 2010.
A Field Guide to the Ants of New England by Aaron M. Ellison, Nicholas J. Gotelli, Elizabeth J. Farnsworth and Gary D. Alpert. Yale Books, 2012.
The Complete Insect by David A. Grimaldi. Princeton University Press, 2023.
The Evolution of the Alarm-Defense System in the Formicine Ants by Edward O. Wilson and Fred E. Regnier, Jr. The American Naturalist, 1971.
The mandibular gland secretion of the ant, Myrmica scabrinodis by E. D. Morgan, M. R. Inwood, M.-C. Cammaerts. Physiological Entomology, 1978.
Antheraea polyphemus entry at University of Michigan’s Animal Diversity Web
Silk Moth blog by the University of Waterloo’s Ecology

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 Green Herons at Pine River Fishing Sanctuary
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Green Herons at Pine River Fishing Sanctuary

On July 6-7, 2024, we had our first Earth Tracks Tracking Apprenticeship weekend for the 24-25.  Our learning and explorations centred around the Orangeville area.  

At two of our meeting sites, both near the Mono Amaranth Townline and at Pine River, we were greeted by the sight of green herons (Butorides virescens- translated meaning “greenish and bittern-like”) calling and flying past.  At Pine River especially, we were able to observe the herons multiple times as they flew up and down the river.

The green heron is described in the National Geographic Society Field Guide to the Birds as a “small chunky heron with short legs, grey-green upper parts , chestnut brown head, neck and upper breast, and a paler brown belly”.  It has a green-black cap with a small crest and a white throat.  The bill is two-toned with a dark upper mandible and yellow lower.  The legs are usually a dull yellow, but the during the height of breeding season, the legs of the male are a bright orange colour.  We were able to see the bright colouration of the legs of at least one of the birds at Pine River.

Green herons winter as far south as Mexico.

I have been fortunate to have green herons nesting at a pond where I work, so thought this blog would be an excellent opportunity for me to learn more about this smaller cousin of the more commonly seen great blue heron (Ardea herodias).

For a full summer I mistook the flight call of the green heron for the chirp of river otters (Lontra canadensis).  But once I was able to put the bird and their call together I began to notice them regularly and was able to identify the rough location of their nest.

In the summer of 2023, we were fortunate to have a young green heron leave their nest and land on a floating mat of moss and other plants in a spot where we were able to observe them for several days.  I invited local photographer Thom Morrisey to come and snap some pictures.  

Though I watched carefully on and off for three days, I never did see a parent feed this youngster and after a few days it appeared to have left. Eventually my curiosity got the better of me and I paddled out to get a closer look.  The baby was still there, just further into the vegetation.  It was spooked by us and it flew back to the area of its nest.  It was very camouflaged until it flew.

While we were not able to locate the nest at Pine River, the frequency of our observation of the birds over the afternoon led us to believe that there was likely a nest on the opposite side of the river.  This assumption was further validated when I found  what appeared to be part of a green heron eggshell in the forest where we were tracking.

 

According to Colin Harrison’s A Field Guide To The Nests, Eggs and Nestlings of North American Birds, green herons breed by water in many habitats including on tussocks or muskrat houses, and at varying heights in trees by both salt and fresh water.  From my observations,  they usually nest near moderate sized ponds around an acre or two in area.  They usually use the same nest site over successive seasons.  Their clutch size ranges from three to six eggs which range in colour from creamy to pale blue-green.

Green herons are opportunistic feeders, preferring small fish (iBird Canada).  From my observations, these birds hunt from branches and trees overhanging the water more than blue herons, who most often wade with their necks extended.

The government of Canada reports that green herons have experienced moderate decline over the past several decades most likely due to the draining of wetlands and the pressure of increased urbanization.  They are not a species of special concern at this time.

Apparently this bird can sometimes develop a tolerance to living near people.  Unfortunately, the pair I have regularly observed did not return to our pond this summer.  I hope it was not because of us.

The opportunity to watch the green herons at Pine River was gift for all of us.  It was special to spend time tracking the shore of the river and observing this interesting species.

 

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Deeper Questions of Common Sign : Tracking at Kinghurst

This past Saturday was another outing with the Earth Tracks Wildlife Tracking Apprenticeship. We went out to the Kinghurst forest in Grey County, Ontario to see what we could find together. It was a small group of six of us, but that made it a little bit sweeter as we could really dig in to all of the things we were seeing.

Things got started for me with finding a White Pine (Pinus strobus) tree that had been recently visited by a Pileated Woodpecker (Dryocopus pileatus) who was in search for food deep within the heartwood of the tree.

This particular White Pine seemed to have been a regular feeding tree for a while. There were three holes which appeared to be from this Winter, and two lower holes which appeared to be from a previous winter, as the wood inside was dark with debris, a bit of what looked like a speckling mould. While the holes created by the woodpecker were pretty severe, the tree was still quite alive as noted by lot of resinous pitch trying to help scab over the wounds in the tree.

When taking a look onto the ground below I noticed a pile of fairly fresh chips which had been chiseled out from the tree. Within this pile there were a couple of small, somewhat tubular, black and white masses, some covered by the fallen woodchips, some sitting atop of them. I got excited to see these as they are incredible signs left behind by the Pileated, detailing the story of what had occured.

This was Pileated Woodpecker scat, which was made up almost entirely from the chitinous exoskeletons of the Carpenter Ants (Camponotus sp.) the woodpecker had been feeding on from the excavated holes. The Carpenter Ants were in the heartwood where they too excavate the wood, creating colonies where they lay eggs, rear their young, and live out their lives. I have read in Tracking and the Art of Seeing by Paul Rezendes that the Pileated listens for the ants in the tree. This could make sense in the Summer when the Carpenter Ants are active, but in the Winter, when the ants are in diapause, how do the Pileateds find the ants? Are they just returning to trees where they know the ants have been in the past? Are they using other senses to find the ants? What about smell? The smell of the tree resins would be pretty powerful and may cover up the scent of any formic acids the ants are producing in the colony, and I actually don’t know if Pileateds have a good sense of smell. Perhaps they don’t?
Another thing I was noticing about this tree is that the older holes are lower on the trunk of the tree and the newer holes are higher up. I have heard and seen that the behaviour of Pileated Woodpeckers excavating lower in the tree is done in Winter as the Carpenter Ants migrate to lower areas on the tree as the ground temperature is warmer than the ambient air temperatures higher up. If this is true, could it then be true that the Carpenter Ants may only go as low as they are compelled to by the cooling Autumn or Winter temperatures? Could we use these woodpecker excavation holes to determine relative chill of the Winters when they were produced? Was the Winter colder when the older holes lower on the trunk were created?
Another question which may be worth looking into in the future would be how the Pileated Woodpeckers deal with the sticky resins which must get all over their bills and perhaps their feathers, too. Do they rub their bills on branches as a bird of prey might when they are cleaning their bills of the gore from their recent meal? Does their saliva help break down the pitch? Do they have saliva? So much to know..

For years I have been identifying a shrub, the Alternate-leaved Dogwood (Cornus alternifolia), otherwise known as Pagoda Dogwood because of the habit of branching in an alternate pattern (leaves branching out from the main stem in a staggered habit) as opposed to most other dogwoods which branch in an opposite pattern (leaves and branches coming off of the main stem in opposite each other, like how our arms branch out from our “trunk” from the same point along the length of our body).
We were checking out the Alternate-leaved Dogwood because we noticed some possible old incisor scrapes on the narrow trunk. Alexis pointed out the incisor marks and mentioned that this was a favorite shrub of the White-tailed Deer (Odocoileus virginianus) to feed on in this part of the world. I hadn’t noticed the faded grey wood which appeared exposed for at least a year. I wondered at why they were incisor scrapes instead of antler rubs? If I remember correctly, Alexis pointed out that the width of the scrapes if taken individually would be too narrow for an antler rub. Also, the height where they were on the shrub may be a little too high for an antler rub. I believe Renato or perhaps Tamara pointed out the clean lines where the teeth entered into the bark at the base of the scrape, as well as the clean exit holes where the deer pulled the bark off of the trunk would be unlikely in the case of the more abrasive antler rubs, which tend to leave frayed uneven edges at the tops and bottom of the wounds in the bark.

In Winter, sometimes a faster way to identify the Alternate-leaved Dogwood is by noticing that sometimes the branches can be a golden yellow colour which appears bright amidst the drab of greys, browns and white. We noticed the same thing while we were out tracking. Sure it wasn’t tracking an animal, but noticing how plants interact with their environments and who interacts with the plants can still teach us about a place, and that is really my end goal. I had noticed this many times before in my neck of the woods and I was able to share that this wasn’t necessarily an identifying feature of the dogwood, but instead a field mark of an entirely different species which was infecting the dogwood!

Especially seen in Winter when the Pagoda Dogwood has lost all their leaves, the Golden Canker (Cryptodiaporthe corni) slowly infects and kills twigs, small branches, and possibly even the main stem of the shrub. Golden Canker is an Ascomycete fungi which likely infects the shrub though wounds in the bark, lenticels (pores in the bark for gas exchange), leaf scars (where leaves were once attached to the twig), or broken limbs though this remains uncertain. When I often see the canker infecting Pagodas along the sides of trails, I have wondered if these particular shrubs were infected through wounds acquired through broken limbs from cyclists or folks running by and breaking off branches accidentally? The fungus gets under the protective bark and may just chill in the tree for a while, not really causing any problems. But something, perhaps drought, or too much Sun, causes stress to the shrub, then the canker can start to reveal itself and the shrub begins to show signs of infection.

I remember when I first looked up Golden Canker; it wasn’t because I wanted to know which fungus was killing off the branches, I didn’t even know it was a fungus! It was from a pure sense of wonder, a question: Why were some of the branches of the Alternate-leaved Dogwoods I was finding yellow? By framing the curiosity in a question I changed how I engaged with it. I was then compelled to look it up, to investigate the unknown. If I tried to label it right away, I would have come to some conclusion and been stuck in a, likely incorrect, diagnosis and never really learned about the relationship between the canker and the shrub. By leaving the question open ended it allowed for all sorts of possibilities, none more possible than another. If I had framed the question in a closed way, with a simple answer, I may not have investigated further. All this reminds me that questions can be more valuable sometimes in trying to see and learn new things than unfounded conclusions and answers are. It reminds me to keep a sense of wonder if I want to learn to see which I cannot yet see in the world.

Keeping on, we found what appeared to by either Coyote (Canis latrans) and/or Domestic Dog (Canis familiaris) tracks and trails. We followed them for a while, measuring strides and individual tracks of the feet trying to find any discriminating sign, but I personally, I couldn’t really settle on one or the other, though the trail did seem rather straight, and didn’t waver much, though the animal may have turned back towards the direction of the parking lot, a behaviour which I usually associate with a dog returning to their human (Homo sapiens).

Thus we began looking at different squirrel trails, including the Red Squirrel (Tamiasciurus hudsonicus) and Grey Squirrel (Sciurus carolinensis). I have heard of different ways of telling them apart but my go to is the trail width. Measurements collected from Mark Elbroch’s Mammal Tracks and Sign indicate that a Red Squirrel trail width for a bounding gait is 7.3 – 11.1 cm (2⅞ – 4⅜ in), while a Grey Squirrel trail width in a bounding gait is 9.5 – 15.2 cm (3¾ – 6 in). This shows an overlap and so I wonder, what are some other distinguishing features to look for in a blurry trail?

What about stride length? High end of a bounding stride of a Red is 63.5 cm (25 in) and a Grey 76.2 cm (30 in), which is 12.7 cm (~5 in) which isn’t much to go on with. Anything else? Sometimes following out a trail can tell us a lot. So that is what I did a couple of times. First one led to a White Pine (Pinus strobus) with a Red Squirrel watching me from the base of the trunk, which was a bit of an easy giveaway. The other led to a ran along a log, past a stump with a Red-belted Polypore (Fomitopsis pinicola) all the way up to a midden pile of old Black Walnut (Juglans nigra) shells. The shells were chewed up on both wider sides and all but a couple with what appeared to be incisor scrapes along the midrib. The few without had no real midrib remaining. This is pretty tell-tale signs of Red Squirrels.

Elbroch writes for Grey Squirrels “[l]ook for their signs spread below many perches, rather than accumulating in large piles below just several perches…” which would be more common for the Reds. Seems like a Red to me.

It wasn’t until a moment later when Alexis asked if I had seen the incisor marks on the polypore? I responded that I did not, but I quickly returned to investigate.

Red-belted Polypores are often found growing on trees in the Pine family, hence the specific epithet “pinicola”, and they have been used in medicine for immune support due to their anticancer, antifungal, and antibacterial qualities (Hobbs, 2020). As I looked at the bracket fungi growing on the stump I wondered if the animal who had consumed some of the outer ring, the newer growth, had understood these properties and was consuming the fungi for these reasons?

My first thought when looking at the fungi was that the Red Squirrel had been feeding on it, but on closer inspection, I started to have my doubts.

Often rodents anchor into a mushroom with their lower incisors and then cut into the mushroom with their upper incisors, cutting away a morsel to eat as they bring the uppers down to meet the lower. Imagine biting into an apple. Now when this happens on a tougher shelf mushroom like the Red-belted Polypore sometimes the incisor marks stick around. The issue I took with the Red Squirrel possibility was the width of the cuts of each of the incisors. They just seemed too small for a Red Squirrel.
According to Mark Elbroch’s book Animal Skulls (Stackpole Books, 2006) Red Squirrel incisors measure 1.06 mm at the smallest. This is even a measurement of the bottom incisors which I do not believe to be the ones used in cutting away a bite of mushroom. I just use this number to illustrate that the smallest data point is still too large for the sign left behind. In light of that, we must assume someone else was mowing down on the mushroom. Two other small rodents in the area would be Deer Mouse (Peromyscus maniculatus) and Southern Red-backed Vole (Clethrionomys gapperi) both of whom may consume fungi. Deer Mouse upper incisor measurements range from .64-.86 mm, with an average of .73 mm. For the Southern Red-backed Vole, the uppers range from .65-93 mm, with an average of about 77.5 mm. These numbers are closer to the the width of the incisor cuts which I estimate at around .7-.8 mm. I estimate because my ruler has relatively thick lines in comparison with the incisor scrapes and no delineation between the millimeter markings to determine the exact number (maybe I’ll ask for a good caliper set for my birthday). Both the Deer Mouse and Southern Red-backed Vole have many recorded instances of consuming fungi, though I cannot find a paper or published article about them particularly feeding on Red-belted Polypore. All in all, I cannot name who I believe it to be between the Red-backed or the Deer Mouse, but I do not believe I saw feeding sign from a Red Squirrel.

As we went on there were some questions around gaits which I thought were pretty fun and I was curious about looking into further. Here is a photograph of one of the gaits.

If you look carefully you can see five toes on either foot, with an alternating patter of a longer tracker beside a somewhat shorter one. This is the trail of a Raccoon (Procyon lotor) whose trail leaves behind the track pattern of their fronts and hinds landing beside each other. Everyone in our group agreed with this assessment. We were wondering which gait created this pattern, are there multiple gaits that leave this pattern, and what was each gait properly called? Gaits are called different things by different authors and sometimes between different animals, notably equine gaits. But I’ll do my best to parse out the details below.

Raccoons move in all sorts of gaits, but they, like most animals, have a preferred set of gaits that they commonly use. One of these gaits is called a pace. A pace is described as when the front and rear on the same side of an animal step forward in unison or nearly so. If I was on all fours and my right front and right hind step forward at the same time and then come down at the same time, or nearly so, and then my left front and left hind step forward and land together and this pattern is repeated over and over, than this is a pace. The University of Minnesota College of Veterinary Medicine website on gaits defines a pace as “a two-beat gait. The two lateral limbs are used alternately for weight support, i.e., the left forelimb and left hindlimb move in unison, as do both right limbs. The forelimb may cycle slightly earlier than the ipsilateral hindlimb.” It is a gait shared by Raccoons, Bears (Ursus spp.), Mountain Lions (Puma concolor), as well as Camels (Camelus spp.), Giraffes (Giraffa spp.), and members of the Elephantidae family. The pace is a gait that doesn’t require as much energy as a trot and has a lower arc of stride, or vertical oscillation in the movement. It’s a pretty chill gait for a Raccoon to use. I have also heard this gait called a waddle since the body sways laterally back and forth as the animal moves forward. I believe that a pace is actually the same thing as a 2×2 walk, but is just a different name. If anyone reads this and disagrees, please let me know. I am here to learn!

Right before we sat down for lunch under a skirt of Spruce branches (Picea sp.) we came across another trail. This trail changed patterns a couple of times, and considering this frequent change, and based on the more rectangular shape of the tracks, the narrow trail and overall size of the tracks we recognized them as s Striped Skunk (Mephitis mephitis). Commonly I see a track pattern representing a transverse loping gait for the Striped Skunk, but it does seem to switch patterns pretty frequently. Let’s review the gaits in the first photo (the one with the boots). From the bottom left I see a group of four tracks made up of a right front, right hind, left front, left hind. This we would call a transverse lope for two reasons; the hind feet do not entirely pass the fronts making this a lope and not a gallop. Secondly, we call it a transverse lope because the trail shows a pattern off footfall going across the body, with the right front landing first, and then the left front. As the left front is leaving the ground the right hind touches down beside where the left front was previously. After the right hind touches down it is followed by the left hind. Both hinds then push off and create a bit of a gap where the animal is temporarily airborne for a moment before the right front lands again in the next group of four. Note that these groups of four are also indicative of a lope where as an overstep walk would be in groups of two, but we’ll take a look at that below.

The trail shown in the fourth photo starts to show that the Skunk is slowing down. How does the trail show this? Starting with the two tracks below and to the right of the ruler, we can see that the longer track of this group of two is directly above the shorter track. The bottom of that group of two is a right front track (RF) and the track above it is from a right hind (RH). These are followed by a left front (LF) and then a left hind (LH). When examining a trail to determine the speed of the animal it is helpful to remember that the further ahead of the fronts that the hind tracks land, the faster the animal is moving. That also implies that the slower an animal is going the further back the hinds will land. Since the hinds are landing just ahead of the front tracks, we call this an overstep walk, as the hinds are overstepping the front. If the animal was moving even slower, than the hinds would land behind the fronts and we would call it an understep walk. If the Striped Skunk were moving a faster than in the photo, we would see that the right hind would land to the right of the left front track, and once these two tracks, the hind of one side of the body landing adjacent to the front of the opposite side, then we move from a walk into a lope, which is what we see in the first photo in the gallery.

Gaits can be confusing, especially when trying to explain through the internet, from someone who is still learning themselves. If you have questions, email me.

As with every outing I could go on and on as I already have, but in hopes of retaining a reader I will include one more observation. But which? Should it be a study of the strange larvae we found in the White-tailed Deer scat? What about the Oppossum (Didelphis virginiana) trail? Or maybe the old tree so decayed by white-rot that I could claw a hole right through to the hollowed out core? Instead of any of these or the many other wonders we encountered I will revisit a subject which has been irking me slightly for the past few months. Ruffed Grouse (Bonasa umbellus) cecal scat.

As I have written of before, Ruffed Grouse have two different kinds of scat. First we’ll cover their pellets. These are tubular scats about 2 cm – 3 cm (~¾ – 1⅛ in) long made up of woody materials. They are usually a pale brown with one end white due to uric acid, though I have found scats where this uric acid appears to have been washed away. The other kind of scat I find is more liquidy amorphous, lighter brown, often nearby to the pellet scat. No discernable or constant measurements as there is no constant form. This scat doesn’t last for a long time and will soon wash away as the rain comes or snow melts.

If these two different types of scat are such a constant in our tracking discoveries, what about them is confounding? Well, why are there different scats? Where in the body do they come from? Do they serve different purposes?

In Mark Elbroch and Eleanor Marks’s Bird Tracks and Sign they write

“Interestingly, after producing these lower-gut-generated solid evacuations, some game birds, such as a grouse, often then evacuate a semi-liquid brownish mass from the upper gut, or cecum, with the two types of droppings coming out sequentially; the more liquid, almost liver-colored scat comes out second and is spread on top of the solid matter. In Ruffed Grouse, it is common to find the hard, fibrous scats at one roost and the soft, brown cecal droppings at another.”

Again, I often find them together, but this isn’t the issue. The issue is complex and I might need a second to explain it.

First what the hell is the cecum? According to few sources I looked into the cecum in birds are two little pockets that stick out of the proximal colon around the junction with the small intestine. Usually they are fingerlike in shape an extend orad (towards to mouth of the bird). Some birds have big cecal pockets, but many have small or no cecum. Birds in the order Galliformes, chicken-like birds like the Ruffed Grouse, Wild Turkey (Meleagris gallopavo), Peacocks (Pavo spp.), and domestic Chicken (Gallus gallus domesticus), all have longer larger ceca compared to many other groups of birds. They also have a bit of a sphincter at the base of the ceca with small villi (tiny little projection which absorb nutrients) which may help to allow fluids to enter the ceca while other particles are passed back into the intestines through waves of involuntary muscle contractions (peristalsis).

From what I understand so far, as all materials pass from the small intestines down to the large intestine, some of the partly digested materials will be taken up by the cecum in a sort of reverse peristalsis, where it will ferment and the cellulose will be broken down further by action of bacteria which inhabit the ceca. The ceca will also reabsorb as much water as possible. The dry firm fibrous pellet scat is made up of the debris which passes through the intestines without getting to the ceca, but the wetter pudding-like scat comes from the ceca. In my research I have both read and heard folks explain that the cecal scat has a stronger scent than the pellet fibrous scat, but I have never noticed this.

However weird this muddy pudding scat seems it is actually very normal and healthy for the birds to pass, and since I have been wondering about the cecal scat of Ruffed Grouse, I believe I have since found cecal scat of Wild Turkeys, too.

Some further questions I have about the ceca and cecal scat are :

  • If the bacteria found in the ceca break down the cellulose, does that mean most of the pellet scat would be made up of lignin based particles?

  • How do parts of the intestines “know how” to separate distinct materials? Are the villi picking up on chemical constituents? Structures of materials?

  • Is the whole process similar with mammals who have cecum? Why do they not have two types of scat?

Above is a video I made on our outing of trying to see the consistency of the cecal scat. You can see how it’s pudding like in texture. In Bairbre OMalley’s textbook “Clinical Anatomy and Physiology of Exotic Species” she writes of birds in general who’se digestion is similar to that of Ruffed Grouse :

Some species use cecotrophy to help survival on rough forage. Food passes down the intestines to the coprodeum by peristalsis. Occasionally an unknown mechanism returns the ingesta by retroperistalsis back up to the cecum. The long villi in the cecum separate the nutrient-rich food from the indigestible portion. High nutrient particles are absorbed and the rest is passed distally in a powerful cecal contraction to re enter the cloaca as cecal droppings. These semi-solid, chocolate-brown droppings are normally discharged about once a day.

In another paper, “Gut Size, Body Weight, and Digestions of Winter Foods by Grouse and Ptarmigan” by Robert Moss he describes the digestive process as :

Briefly, the gut is generally full of digesta day and night. The crop is filled with food shortly before going to roost and this store is passed into the gut and digested during the night. After being ground in the gizzard, digesta pass through the small intestine. At the junction of the small and large intestines are two long tubular diverticula, the caeca, into which the more liquid fraction of the chyme is diverted and where it ferments. The more fibrous fraction of the chyme passes by the caecal entrances into the large intestine and is rapidly and regularly egested. The major emptying of the caeca occurs once daily when the bird is about to leave, or has just left, its roost.

Both of these quotes are better descriptions than mine above. I thought I would include them instead of trying to paraphrase. Sometimes that’s easier and just makes more sense.

—

This has been a rather long entry that has taken nearly two weeks to write. I don’t know how much sense it will make, but I find it useful to go back and review the things we know and try and take a deeper look into the how we know them, and into the literature to confirm or challenge how we know them. I want to get better at not only seeing the tracks and sign left behind, but to better understand the how and why it got left behind. From there, I want to be able to better project, to hypothesize, what other sign could look like, though imagining the forms and functions of the animals. I figure I can only do this by knowing the ecologies of the animals better, and by knowing who they are. Ironically, we can do this better by knowing their tracks and sign. I guess it’s a cycle of attention and focus.

To Learn More :
Tracking and the Art of Seeing by Paul Rezendes. Harper Perennial, 1999.
The University of Minnesota Extension page on Golden Canker
Mammal Tracks and Sign by Mark Elbroch and Casey McFarland. Stackpole Books, 2nd ed., 2019.
Medicinal Mushrooms by Christopher Hobbs. Storey Press, 2020.
Animal Skulls by Mark Elbroch. Stackpole Books, 2006.
Mammalian mycophagy: A global review of ecosystem interactions between mammals and fungi
University of Minnesota College of Veterinary Medicine website on gaits
Bird Tracks and Sign by Mark Elbroch and Eleanor Marks. Stackpole Books, 2001.
The Avian Cecum : A Review
Clinical Anatomy and Physiology of Exotic Species by Bairbre OMalley. Elsevier Limited, 2005.
Gut Size, Body Weight, and Digestions of Winter Foods by Grouse and Ptarmigan by Robert Moss. The Cooper Ornithological Society, 1983.

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 Sign of Birds in Algonquin Park
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Sign of Birds in Algonquin Park

This year I wanted to keep birds in focus and at front of mind in my ongoing learning about wildlife tracking. I wanted to do this because birds are often overlooked when folks think of looking for tracks and sign in the field, even though there is often so much to find. Obviously track and sign is a way to really get to know the birds better and to deepen our relationships with them, and I wanted to continue along that path, especially since it can be hard to find good resources or tools to help interpret what we are seeing on the land.

While in Algonquin Park this past week with the Earth Tracks Winter Wildlife Tracking Trip I tried to pay more attention to some of the bird sign throughout our days, though I didn’t always get some good photos, and I missed recording some beautiful songs and calls. I will share however what I did find in the park and what I have been able to learn thus far.

 

Pine Siskin (Spinus pinus)

Pine Siskins were my focal species for the week. That meant that every night before I ate I would research something particular about the Siskins and share this fact or discovery with the group. This was a great intro to the Siskin and helped me realize I didn’t know much at all about them… which was just the right inspiration to learn more.

On our final day in the park, Alexis came back from his scouting mission carrying in two Siskins he had found dead on highway 60. We had been seeing them every morning during our scouting missions, in small flocks, sometimes at the edge of the road, sometimes hanging out on the yellow line. They had likely been attracted to the road due to the salt. I took a lot of time to investigate the little bodies, looking at their feathers and measuring their feet. The right feet on both dead birds measured 27mm L. Toe 1 (also known as the hallux) seems to be closer to the inside of the foot and the talons appeared quite long compared to some other birds I’ve got to hold.

The Siskins had beautiful yellow wing bars and edges of yellow on their tail feathers (retrices). I have read that male Pine Siskins from Southern populations have more yellow in the wings than females, but sexual dimorphism in the Northern populations may be more challenging to sort out as the colour differences may be much more subtle. A bird biologist friend told me that when studying Pine Siskins in the field, they use both wing length as well as size and brightness of the yellow marks on the bird to sex these birds in the hand. I sadly did not get the chance to measure the wing lengths. Using a chart created by the McGill Bird Observatory’s Migration Research Lab, I believe these birds to be both second year males, but I am still new at this.

Finally, the Pine Siskins are notable for some of their boisterous bubbling tinkling raspy high pitched song and their calls which remind me of TIE fighters flying by in Star Wars. What does that mean? Try and pick out the quick vvvrreeeee rising in pitch within this chorus of Pine Siskins, Red-breasted Nuthatches (Sitta canadensis) and Black-capped Chickadees (Poecile atricapillus) :

 

Red Crossbill (Loxia curvirostra)

One morning while out scouting on highway 60, we stopped to check out some tracks on the side of the road and Alexis noticed a Red Crossbill laying still in the middle of the road. I ran out of the truck and went over to pick them up to see if they were still alive, not expecting much. The bird was dead, but so newly deceased that they were still very warm despite the -8°C (17.6°F) temperatures. Their neck had been broken, likely hit by a truck headed West just before we got there. Again, it was also likely that the Crossbill was on the road attempting to consume salt. Researchers suspect the Crossbills find the road salts to be an easy source of minerals which they require in their diets.

Despite getting the chance to hold and really look close at the Crossbill I did not think to measure the foot length.

Tyler Hoar of the Finch Research Network writes that the Winter of 2023-2024 is a big year for Red Crossbills throughout Southern Ontario due to a sparse year of Spruce cones in the Northern boreal forests where a lot of Crossbill visitors are coming from. They have come South in search of a large crop of White Pine cones and seed. When birds come down looking for better food sources we call these irruptive years. This is true for the Pine Siskins as well, although they have a more generalist seed eating diet than the more specific Crossbills.

The Red Crossbill’s diet can be pretty damned specific. There are different populations of Crossbill whose bills have evolved to specialize in opening cones and retrieving seeds from specific conifer species. Some may be better able to wedge their bills into a White Pine, while others may be better suited to extract and husk Eastern Hemlock (Tsuga canadensis) seeds. In Cornell’s Handbook of Bird Biology (3rd ed., 2016) I read about a study where they had two populations of Red Crossbills from different geographic regions (Rocky Mountain (RM) and South Hills (SH) regions) try and open the cones of Lodgepole Pines (Pinus contorta) originating from the two distinct areas where the two populations of Red Crossbills were from. RM Crossbills could open the cones from their own region in 5 seconds, and the cones from SH in about 7 seconds. The SH Crossbills could open RM cones 13 seconds, but cones from their own SH region in 6 seconds! This is theorized to be due to coevolution in with the Lodgepole Pines in their own territories which helped shape and specify their bills to match their local Lodgepole, a coevolution which is also influenced by the presence of Red Squirrels (Tamiasciurus hudsonicus) who feed on the seeds from the Lodgepole Pine cones. I am curious to know if the Red Crossbill we found, and those we heard throughout the week, have specific relationships with specific species in the park, or whatever home region they are from up in the boreal forest?

Red Crossbills aren’t just reliant on a the conifers for a good food source. While other birds, who mostly mate in the Spring when their mating hormones are triggered by a longer photoperiod, Crossbills tend to breed opportunistically, like when they find an abundant seed crop. This makes sense on a lot of levels as a Human (Homo sapiens). I feel that coming across the abundance needed for producing a clutch would be the most appropriate time to mate and begin nesting. The lengthening photoperiod (the period of light in a day) and promise of Spring are general securities for raising young, but the immediate abundance seems like a good motivator. I wonder what other factors there are that influence the mating period that Humans just don’t know about?

Black-backed Woodpecker (Picoides arcticus)

White Pine (Pinus strobus) trunk with the bark scaled off. Rock Lake, Algonquin Park, 2024.02.14.

This is the first year of the Winter Wildlife Tracking Weeklong that I have managed to remember to get a photo of this incredible and extensive behaviour likely done by Black-backed Woodpeckers. What’s going on in the photo? This is a large White Pine tree which has had a ton of the outer bark chipped off. I think in the field we may have called this behaviour bark sloughing, which is when a bird removes the entirety of outer bark of a tree. Rather than sloughing, this tree looks like it has had the outer scales of bark removed, which is called bark scaling. I have read both terms used interchangeably or to describe the opposite of what I have described above; scaling for when the entirety of the bark is removed and sloughing for when only chips of outer bark has been removed. Despite this confusion, I am going to stick with these definitions previously mentioned: here, bark scaling means chipping at outer bark only, while sloughing implies removing larger pieces the bark down to the wood.

The bark scaling behaviour in the photo above is a common enough sight in Algonquin and I feel I have seen it before on other Pines, Hemlocks, and maybe even other trees such as some of the Firs (Abies spp.) or Spruces (Picea spp.). Why are they sloughing the bark? To get at small bark boring beetles which live and feed below the outer bark. Who is the insect which the Black-backed Woodpecker was feeding on? Likely the Hemlock Borer (Phaenops fulvoguttata) which is a common small (8-11 mm L) bark borer in found throughout Southern Ontario. The Hemlock Borer is black with three yellowish spots on each elytron (wing covers) in a crescent pattern. They have been recorded on different species such as the Balsam Fir (Abies balsamea), Tamarack (Larix laricina), White (Picea glauca), Red (P. rubens), and Black Spruce (P. mariana), and again, the White Pine and Eastern Hemlock. The Hemlock Borer and other bark boring beetles (Buprestidae) show up more readily on trees which are already dealing with heavy environmental stressors such as low water availability, high tree density, or recent fires. And, in another instance of a bird co-evolving with other species in their environment, researchers believe that the Black-backed Woodpecker has black plumage all down their back because of this diet of bark boring beetles. Black-backs have evolved to be camouflaged against the blackened barks of fire scorched conifers where, again, their bark boring beetle prey deposit their young and where the larvae grow. What a cool adaptation! While burned areas are preferential for P. arcticus, they may also be found frequenting boreal forests with conifers and aspens.

Likely galleries of the Hemlock Borer (Phaenops fulvoguttata) exposed by Black-back Woodpecker (Picoides arcticus) bark scaling.

Pileated Woodpecker (Dryocopus pileatus)

While out with a small group on the Thursday of our weeklong adventure in Algonquin we came across a beautiful dead trunk, likely of a Big-toothed Aspen (Populus grandidentata) full of diverse animal sign. We found Beaver (Castor canadensis) chews at the bottom which girdled the tree and likely initially wrought the tree’s doom, along with a number of large Pileated Woodpecker holes with Carpenter Ant (Camponotus spp.) galleries within. The larger Pileated holes can be pretty wide and fairly long (I have measured one at 75 cm, or 29½” long, and I have seen larger) and deep enough to peer into the dark hollowed heart of the tree where the Carpenter Ants have set up their colonial homes.

If you look carefully along the side walls of the Pileated holes, you can often find the marks of the stout bill of the woodpecker from when they were repeatedly smashing their heads against the tree. It seems that for a long time researchers have wondered how all of the woodpeckers who smash their bills against the trees can do this without suffering from any sort of brain damage. Some folks talk about the tongue of many woodpecker species being so long that it wraps around the braincase acting as a cushion for the brain, similar to an air bag in a vehicle helps reduce injury in the case of an accident. Another paper I found was all about how woodpeckers can’t get concussions when using the amount of force that they do. They write that despite smashing their heads with accelerations up to three times that of the human concussion threshold that “these [woodpecker] species would need to hit their selected spots twice as fast as observed or strike at its top speed on wood that is four times as stiff to suffer a concussion.” The video abstract from their paper is embedded below.

Back to Algonquin, this tree we were examining was a special tree, not only for us but also for all the species which had interacted with the tree since they had died or been in decline.
While we were attending to the varied sign on the tree, a Pileated Woodpecker flew in and began hammering away at the wood in another Populus tree just off to the side of where we were standing. We watched silent and still for quite a while, and then began to move a little bit hastier and noisier once we realized our movements weren’t likely to push off the Pileated. We made our way up a small hill back to the trail and realized we were on the same level as the great bird. We stayed with the bird, watching how they titled their head this way and that to gain better leverage to chisel away at the rotten trunk. When we heard a snowmobile coming we stepped off the trail once more. The Pileated took off and alighted on a another nearby tree but this time further into the brush of the forest. Once the roar of the engine had passed, the woodpecker returned and got back to enlarging their new cavity. We noticed some hesitation now and then in the head movements of the bird and realized thought that this was when they were actively feeding on the insect prey inside.

A question I have, which I was actively looking out for in Algonquin, was if Pileated Woodpeckers tend to create their feeding holes on the South side of the trees more often than other directions? By the end of the week, it seemed the total number of holes facing South seemed higher than holes facing any other direction, when counted individually, but the South facing holes were not what I saw the majority of the time. In my follow up research I read the Pileated Woodpecker chapter from Life Histories of North American Woodpeckers by Arthur Cleveland Bent (who used the scientific name of Ceoploeus pileatus abieticola Bangs for the bird) and there he notes that his correspondence all seem to agree that most of these holes are done in the Winter. I find this intriguing because this is what I have seen as well when it comes to the excavations made closer to the ground. Why closer to the ground? As the months grow colder, Carpenter Ants tend to congregate in the warmer parts of the trees, and in Southern Ontario that means down near the bottom of the trunk, or the bole as it is sometimes called. The ants gather closer to the ground as the ground temperature is warmer than the Winter ambient air temperature. The ants then enter a state of diapause where development and growth is stilled until warmer temperatures return, usually lasting between 3 – 4 months, though I wonder if the ants become active during the warmer breaks in Winters like this year?

From Bent’s chapter on Pileated Woodpeckers, also known as Log-cocks:

Of the major wintertime operations Vickers (1910) has written:

Like the flicker, the [pileated woodpecker] is a great lover of ants, which accordingly occupy a large place in his bill-of-fare. So, to dine on the big black timber ants, which are his special delight, he drives holes to the very heart of growing forest trees, tapping the central chamber of the colony, where, in winter, he finds the dormant swarm unable to move and feasts upon them at leisure. . .And the Log-cock makes no mistakes, though man might find no outward sign of an ant-tree. Doubtless that strong formic smell, coupled with his experience in sounding tree trunks–as a man tells a ripe watermelon by the ‘plunk’ of it–enables him not only to find the tree, but, what is more remarkable, to drive his hole with such precision that he taps the heart of the community.

The Pileated holes often become homes for other animals as well, such as Flying Squirrels (Glaucomys sabrinus and G. volans), owls, Peromyscus mice, and likely more. I wonder if these animals may feed on the ants within as well? Also, how much bark scaling or sloughing would a Pileated get up to? So many questions.

Ruffed Grouse (Bonasa umbellus)

Throughout the week there were quite a few trails made by the Ruffed Grouse. Often an indistinct trail in the melted and blown over snow, the trail could be sorted by looking at the width and seeing where it appeared to suddenly begin or surprisingly stop.

The Ruffed Grouse isn’t the only grouse in the park, as the Spruce Grouse (Falcipennis canadensis) are also present, though I have heard more commonly found on the Eastern side of the park. Their tracks are very similar according to Elbroch (2001) with the Spruce Grouse tracks measuring 3.8 – 5.7 cm (1½ – 2¼ in) L x 5.1 – 6 cm (2 – 2⅜ in) W and the Ruffed Grouse coming in at 4.1 – 5.7 cm (1⅝ – 2¼ in) L x 4.4 – 6 cm (1¾ – 2 ⅜ in) W. While the trails of the Ruffed Grouse can be confused with some other species it is good to look for the game bird tracks, similar to Wild Turkey (Meleagris galopavo) though smaller.

Another sign of Ruffed Grouse are their two types of scat we found. First type of scat was their liquidy, or frozen, cecal scat which is often pale brown and often sunken somewhat into the snow, when there is any. This scat doesn’t last for a long time and will soon wash away as the snow melts. The second type of Grouse scat seems to persist quite a bit longer. It appears as a dry, compressed tubular pellet with a slight crescent-like curve to them, often with a bit of white uric acid on one end. These scats are made up of tiny pieces of plant material which did not breakdown throughout the digestive journey.

When monitoring Ruffed Grouse snow roosts (learn more about Ruffed Grouse snow roosts here), biologist, author, and writer Bernd Heinrich noticed that the Ruffed Grouse were depositing roughly 3.7 fecal pellets per hour. This has become a bit of scat math that I have come to practice whenever I come across Ruffed Grouse scat in the woods (thanks for the hot tip, Tamara!). By looking at the images you can get an idea that the Grouse who expelled these pellets was likely there for over 8 hours. When it comes to food, Bernd also noticed that in only 15 minutes the Grouse can fill their crops with enough tree buds to last them through the night. I imagine then that a Ruffed Grouse only needs to be up and bopping around for such a short period of time. This is a great strategy to minimize energy waste throughout the colder times of year.

—

Now there is so much more I need to learn about when it comes to bird sign, and it is going to take more years of observing and researching, and likely stepping up how I observe, record and even setting up some more experiments to get at the answers I am after. For now, I am grateful for the birds and the lands they inhabit and shape, for Alexis and the apprenticeship, and for everyone who came out for the Winter Wildlife Tracking weeklong in Algonquin Park. And just so you know, next year’s dates are Feb 9th – 14th, 2025, so save the dates!

To learn more :
McGill Bird Observatory’s Migration Research Lab
Winter Finch Forcast 2023-2024 by the Finch Research Network
Cornell’s Handbook of Bird Biology edited by Irby J. Lovette and John W. Fitzpatrick. Wiley-Blackwell, 3rd ed. 2016.
10 Types of Woodpecker Holes and Other Woodpecker Sign on Trees
Peterson Reference Guide to Woodpeckers of North America by Stephen A. Shunk. Houghton Mifflin Harcourt, 2016.
Woodpeckers minimize cranial absorption of shocks paper by Sam Van Wassenbergh, Erica J. Ortlieb, Maja Mielke, Christine Böhmer, Robert E. Shadwick, Anick Abourachid
Life Histories of North American Woodpeckers by Arthur Cleveland Bent. Smithsonian Institution United States National Museum Bulletin, 1939.
Bird Tracks and Sign by Mark Elbroch. Stackpole Books, 2001.
How Do Birds Survive The Winter? by Bernd Heinrich

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