A mad dash to the final line!
Despite the much anticipated – and extremely late – arrival of American Redstarts on May 16, not much of note happened during the first few days of the second half of May: between May 16 and 19, daily diversity ranged between 42 and 52 species, with no major movements of migrants. The weather was still quite cold, with frequent overcast conditions and East winds. No precipitation fell at the station during this time but rain was frequent to the South of us, which could have slowed migration.
I write “not much of note happened” but that is slightly misleading: it is Cabot Head after all! That said, a Green heron was seen flying over Wingfield Basin on May 16, a species seen only occasionally around the station; on May 18, an adult Peregrine Falcon was perched on Middle Bluff for a long while; later, that day, a fast flying shorebird crossed the sky, intent on a destination known only to itself. The pure white belly, short neck and legs, and all dark wings gave it away as a Solitary Sandpiper. Still on May 18, alarm calls of crow alerted my gaze across Wingfield Basin, where I discovered a very large bird flying low along the shoreline mobbed relentlessly by two crows: an eagle but not a bald one, instead an immature Golden Eagle! It perched briefly on the top of a spruce, but, still being harassed by the black sentinels of the woods, it took off to find a quieter spot. Luckily for me, that spot was a large log underneath Middle Bluff, where I could admire it at leisure. I was delighted: having missed it last Spring (for the first time in all my Spring seasons), and having resigned myself to not seeing it this year. Indeed, all observations but three have been before May 8, which is when I started monitoring in the strange year of 2020. But, there has been later observations: in 2015, it was May 18, and in 2011, it was May 25 and 29 (likely the same bird that year). After a while, the 2020 Golden Eagle finally took off once more and disappeared towards the southern horizon, only to better return about an hour later for a much appreciated Encore!
Despite that exciting observation, it was a somewhat subdued few days in terms of migration, which made the following few days even more striking. On May 20, it was a mad dash to the finish line! As if held up for a long time, birds were pouring out from the brilliant blue sky in a multihued mix of diversity and in incredible numbers against a fresh East wind. Most birds were flying just a little too high and too fast to be positively identified, except maybe in a broad category, like “Warbler sp.” (unknown warbler): I got about 500 of these at the end of 6 hours of observations! But I also properly identified 20 species of warblers, with a FOY Blackpoll Warbler, and many of them in hard-to-believe numbers: Nashville, Chestnut-sided, Blackburnian, Black-throated Green Warblers, as well as Northern Parula and American Redstarts. As an example of this striking event, there were five Northern Parulas at once in a few trees, mostly males; and later, I would observed three females in one cedar.
That day, there were also many, many Rose-breasted Grosbeaks: a record daily high of 24 birds were counted! Most of them were second-year males (born last year), as evidenced by the brown wing and tail feathers contrasting with the jet-black wing coverts (the small feathers of the “shoulder”). I could sometime see up to five of them in a tree at once!
A feast of feathers and colours! The FOY Scarlet Tanager was one single bright red streak against a deep blue sky. The FOY Indigo Bunting burned blue in a white birch, posed long enough for me to admire its, well, indigo feathers. A smattering of male Baltimore Orioles brought deep orange and raven black, to compete with diminutive Blackburnian Warblers and American Redstarts.
In this most diverse day, the four species of vireos were observed, FOY for Warbling, Philadelphia, and Red-eyed, alongside the previously detected Blue-headed! The Tyranidae family was also out in full force: Yellow-bellied and Least Flycatchers, FOY Eastern Wood Pewee, the local Eastern Phoebes, and quite a few shrieking Eastern Kingbirds flying fast in their striking white and black. Bank and Barn Swallows were also observed for the first time this Spring, adding diversity to the usual Tree and Northern Rough-winged Swallows. One single Chimney Swift flew by the only way swifts know; fast and furious! It is a species so easy to miss for that reason. Among raptors, there were kettles of Broad-winged Hawks, accompanied by a few Red-shouldered and Red-tailed Hawks. A Peregrine Falcon was also seen briefly. And, to crown the morning, her majesty the Golden Eagle returned at the end of the monitoring period to claim the 84th species mark! The 85th species was an “unofficial” Osprey, flying so low and so close I could distinctly see its yellow eyes [unofficial because recorded after the seven hours of monitoring but still very much appreciated].
Reaching, let alone surpassing, 80 species detected in the seven hours of monitoring has not happened often in the history of Cabot Head: in the previous 18 Spring seasons (Diversity in Fall is always lower), 18 days have achieved this milestone, with the still quite unbelievable record of 99 species on May 21, 2011.
After such an eventful day on the 20th, May 21 started with stillness of air and coolness of head: there were no wave-upon-wave of hurrying migrants crossing the still impeccably blue sky. I proceeded with my day, duly noting every species seen but not quite realizing that there were still so many of them. The lower numbers probably fooled me and I was quite shocked that the daily tally reached 81 species (including two only detected through banding)! Seven of these species were different from the preceding day, notably one Red-bellied Woodpecker and three (3!) Red-headed Woodpeckers, all seen in a span of a mere few minutes. There were far fewer Rose-breasted Grosbeaks, but more Baltimore Orioles, than the previous day. Warblers were again at their peak with 21 species, including a rare Prairie Warbler! I was first alerted to its presence by its thin, buzzy, ascending song before being able to observe it for a few minutes. I noted all the telltale marks: the white outer rectrices, the yellow face and body with black streaking on the flanks, the black crescent under the eye, the thin black eye line, the dull green cap and back, as well as the hard to see little chestnut feathers on the back. It is only the fourth Spring season with a sighting, a definition of rare for sure.
Finally, there was some respite for my eyes and ears on May 22 when “only” 60 species were detected, although including a Vesper Sparrow and a late White-crowned Sparrow. It felt like Summer was here: a lot of birds were singing on territory, the trees were proudly showing off their fresh green leaves, angry hummingbirds were fighting for access to the feeder. Nonetheless, migration is not over yet, as shown on May 23, with still new species to arrive: among the 70 species detected (including 17 of warblers), there were FOY Tennessee Warbler and Olive-sided Flycatchers, typical late migrants. The days in the pastures and fields of southern Bruce paid off when I (finally!) heard the flight call of a Bobolink, duly confirmed with a visual observation. Another call gave away not one but two Blue-gray Gnatcatchers, an almost yearly occurrence at Cabot Head, despite the fragile toehold this species has on the Bruce Peninsula.
On May 24, there was no day off for yours truly: up again and eager to see what the day might bring, “expect the unexpected”. But I was definitely not expecting the spectacle of Scarlet Tanagers streaming through the area, with a tally of 16 (sixteen!) in about 30 minutes, and a record-breaking total of 23! Adult males in scarlet and black, second-year males in scarlet and black and brown, and females in more subdued yellow and green: it was as though all age and sex classes were eager to reach their destinations before the storm, as the western horizon was darkening and the ominous rolling thunder was getting closer and closer. There was indeed a strong movement again on that day, with, notably, lots of Magnolia and Blackburnian Warblers. I even doubted my eyes, thinking I might do some double counting: the warblers were lingering and feeding a lot in the trees, as opposed to the mad dash of a few days ago. However, when one net was filled at once with four (4!) Blackburnians and three Magnolias, I realized that I was likely underestimating their numbers. The storm arrived mid-morning, dimming bird activity. But not for our resident Bald Eagle: I observed it dining on a Cormorant at the tip under driving rain! After the one that escaped two weeks ago, the eagle had been successful on Wednesday, I noticed when I surprised it while going out in my kayak. It seems that the eagle has become specialized in preying on Cormorants.
These were unique days, the ones every birdwatcher dreams of, when the marvels of migration are in full display in both number and diversity.
Stéphane
Please encourage Ted’s Birdathon: https://www.canadahelps.org/en/charities/bird-studies-canada/p2p/birdathon20/team/bpbo-corvid-2020/