Categories
Nature Observations

Return of the Ravens

Ravens are awesome, beautiful birds.

My parents’ farm property in Norfolk County has been blessed by the construction of a very exciting nest. One day when I arrived at their house and opened my car door I was greeted by the distinctive “croak” of a Common Raven (Corvus corax). The sound startled me, placing me in the woodlands of Algonquin Park, but there was no mistaking that call, and the size of the bird making it. I could see the calling raven, perched atop an unused silo. As exciting as this brief sighting was, the true significance of this bird’s presence was not yet revealed.

Later that same week, my Mom asked about the large crows and mentioned that they were building a nest on top of the silo. She said they went back and forth with sticks in their beaks. Maybe this news wouldn’t be so exciting to some people but for myself the thought of a raven nest that I could regularly observe was exhilarating.

And observe it I have!

On a recent visit, I went back to check out the nest and take some pictures. After only a few moments of watching the silo, I heard the sounds of one of these amazing birds returning and saw it carrying a  large stick in its beak. The raven dropped the stick onto the nest pile without even landing, continuing to soar through the sky on its powerful wings. Apparently, if a dropped stick doesn’t stay in the nest, the ravens won’t pick them up again off the ground (Stokes and Stokes 1989). The sticks are taken from tree branches, broken off by the ravens, not collected from the ground (Stokes and Stokes 1989). In addition to large sticks, the nest could contain dirt and grass clumps as well as an interior lining of gathered hair or bark (Stokes and Stokes 1989).

The raven didn’t even land, just dropped the stick from the air onto its nest.

A few minutes later, a turkey vulture (Cathartes aura) came drifting towards the silo. The large bird seemed to be planning to perch atop the silo, something I have seen vultures do previously. Swooping onto the scene with deep throaty “croaks” the raven pair chased the vulture off into the distance, something that was reminiscent of the classic behaviour of corvids mobbing raptors or owls.

One of the ravens pursuing a turkey vulture.

As I said at the beginning of this post, the call and sight of ravens makes me think of Algonquin Park, and that’s for good reason. Until now, it was the only location I had seen these birds. Ravens used to be common across all of Ontario but mainly due to habitat destruction and human persecution, they have been mostly absent from far southern Ontario for about a century (Cadman et. al. 1987). Ravens were even rare in Algonquin Park until the 1960s because of the poisoned baits left out for wolves (Tozer 2012). The most recent field guide I have (Bezener 2016) still has the raven range map cut off before reaching most of Southern Ontario.

I’ve tried unsuccessfully to find a good source for the current breeding range of ravens in Ontario, but I suppose I’ll have to wait for the next edition of the Breeding Bird Atlas, which is collecting data right now (2021-2025) for its creation. It’s an amazing project, and if you have the time to contribute go for it! Suffice to say, this nest of ravens is a fairly new thing in my area and is very exciting. I hope that they have a successful nesting season, and I have a feeling I will have more posts about this nest in the future! At the time these observations were made (March 29, 2022) the ravens have possibly already laid eggs in the nest, as Tozer (2012) gives a range for Alqonquin raven egg-laying as March 20 – April 19. Stay tuned!

Raven and turkey vulture, showing nicely the relative wingspans of these two large birds.

References:

Bezener, Andy. 2016. Birds of Ontario. 376 pp. Partners and Lone Pine Publishing.

Cadman, M. D., Eagles, P. F. J., and Helleiner, F. M. 1987. Atlas of the Breeding Birds of Ontario. 617 pp. University of Waterloo Press.

Tozer, Ron. 2012. Birds of Algonquin Park. 474 pp. The Friends of Algonquin Park.

Stokes, Donald and Stokes, Lillian. 1989. A Guide to Bird Behavior. Volume III. 397 pp. Little, Brown, and Company.

For Previous articles that have some relevance to this one, see:

Canada Jay (Perisoreus canadensis)

Algonquin Observations, Part 3 – Peck Lake Trail

Fuzzy Flies and Song Sparrows

Categories
June 2021 Observations Nature Observations

The Wonders of Wrens

Twice on the Lynn Valley trail this past month, I managed to get some pictures of Wrens singing. These tiny birds burst with song much larger than themselves and it’s always a treat to see or hear them. 

When I saw and photographed the two Wrens, I assumed them to be the same species, and even possibly the same individual bird. I had found them in the same general location on the trail, separated by about a week and in location maybe only 100 metres away from each other. After submitting the pictures to iNaturalist (a website I use extensively for my observations and identifications), they were identified as two separate species in the same Genus. The Genus was Troglodytes, an evocative title for such small birds, one that stems from their habit of nesting or foraging in hidden holes, which I suppose are like caves. My first Wren spotting was a Winter Wren (Troglodytes hiemalis).

Winter Wren

The Winter Wren constructs its nest of twigs and moss and often hides it in one of the most incredible places: the tangled roots of fallen trees (Bull and Farrand Jr., 1994). When I encounter fallen trees, I have often been struck by the vertical clifflike nature of the mass of dirt still held fast by thick tree roots. On these miniature cliff faces, the Winter Wren hides its nest, and hides it so well that they are notoriously difficult to find. Bernd Heinrich, in his excellent book Winter World, describes the nest as “a snug little cavity with walls camouflaged with a lattice of moss and conifer twiglets” (p 61). Amazingly, only the Male Wren constructs the nest (at least in the two Wren species I’m writing about here) and he will often create more than one as part of his territory, from which the female can choose her favourite. When the female chooses one of these nests, she will add the lining of fur or feathers and the male will know that his territory has been accepted (Stokes 1979). This strategy of nest building (though not the nest location) applies to the other species I spotted on the Lynn Valley Trail: the House Wren (Troglodytes aedon).

The most conspicuous feature of Wrens (the Family Troglodytidae) in my experience is their stiff little tails and the way they flick them around often perpendicularly to their backs. According to A Guide to Bird Behavior, the tail is raised more and more to the vertical with increasing excitement or disturbance. This seems to indicate that I’ve rarely observed calm Wrens. House Wrens don’t nest among the upturned roots of fallen trees like the Winter Wrens, but instead in a natural or manmade cavity. The House Wren’s acceptance of human-made structures for nesting is the origin of their name. Besides nesting in nest boxes constructed by people for birds, House Wrens will apparently also nest in mailboxes, flowerpots, and jacket pockets that are hanging outside (Bull and Farrand Jr. 1994). I can think of few more appealing things to find in my jacket pocket than the nest of a tiny bird.

References:

Stokes, Donald W. A Guide to Bird Behavior. 1979.

Bull, John and Farrand Jr., John. National Audubon Society Field Guide to North American Birds: Eastern Region, 1994.

Heinrich, Bernd. Winter World, 2003.

For more Bird Observations, see:

-Nature Observations: Pinery, Winter 2019

-Feeding Opportunities

-Eaters of the Dead

And for more photos and natural history check out my instagram: norfolknaturalist!