The return of the cold! ￼
Despite the continuous arrival of birds from tropical locales, the temperatures this week reminded us forcefully that we still live in Canada. There was frost on the ground on Thursday, May 18, a stark and clear statement that one should never put away one’s toque (beanie for our American friends) at the bottom of a drawer too soon in Canada. Actually, one should always have their toque on hand almost any time of the year in the Great White North! The weather was actually quite bearable on that Thursday, since there was no wind. The previous day, on the other hand, a cold North wind blew all day and with it, all our hopes of catching many birds. Indeed, the grand total of the day was 7 birds of 5 species! With the cold, barely any insects stirred, which also meant that very few birds stirred. How do they cope, then? Likely by staying put and fluffing up their feathers in sheltered thick cedar boughs. Some might engage in reverse migration, flying in the opposite direction of their expected migration (i.e. South in Spring), to find better feeding conditions, but the extent and magnitude of this phenomenon is still poorly understood.
The beginning of the week was thus very quiet, except for very large flocks of Blue Jay (up to 200 birds!), with very few birds around and in the nets. However, that was about to change, in the usual boom and bust pattern of Spring migration.
Despite frost on the ground on May 18 in early morning, the air warmed up slowly but surely during that day, with an easterly wind picking up in late morning. East winds are usually a harbinger of rain on the way, be it in a few hours or a few days. Impending rain systems are very often preceded by a strong movement of bird migration. Indeed, that Thursday May 18, 45 birds of 22 species were banded, including 34 birds of 12 warbler species. It was a warm up for the following day…
On May 19, an impressive 113 birds of 27 species were banded, with an overall 87 species detected during the day, the highest diversity of the Spring so far. After its first appearance on May 11, Least Flycatcher were seen in ones or twos. But on May 19, 5 were banded and 8 more were observed. Philadelphia and Warbling Vireos were detected for the first time this year, with one banded and two observed, respectively. Quite a few thrushes were banded too, with 9 Swainson’s, 2 Veeries, and the FOY Gray-cheeked Thrush. The FOY Gray Catbirds were also detected and banded. The stars of the show were the wood warblers again, with 73 birds banded of 15 species. We had the FOY Mourning Warbler. The striking Blackburnian Warbler kept landing in our nets, with 7 birds banded, a high daily total for Cabot Head: records are 8 and 10 birds in 2022 and 2019, respectively. After a day with 10 birds earlier this Spring, a total of 8 Ovenbird were banded; most days are only one or two banded for this species. But the real record breakers were: Bay-breasted Warbler with an impressive 11 birds banded! Previously, the highest daily total was 7 birds (on 2 occasions in 2006 and 2019). A remarkable 10 Tennessee Warblers were also banded; this species is actually rarely captured in Spring (as well as in Fall except for a few seasons): Tennessee Warblers were banded in only 13 in the last 21 Spring seasons, with captures on 24 days in total and the highest banding daily total was 2! Yes, two birds in 2 occasions both in 2019 were the most Tennessee Warblers ever banded in one day. Previous season totals range from 1 to 2 in 11 Spring seasons and 5 birds in 2019 and 6 birds in 2002. So, having 10 Tennessee Warblers banded in one day is unprecedented at Cabot Head.
In that fateful day of May 19, Ted’s excellent ears and eyes detected unusual shorebirds: 3 Semipalmated Plovers, 15 Least Sandpipers accompanied by one Ruddy Turnstone. The latter species was detected only once before, with 5 birds on August 27, 2011. A Green Heron was heard at dawn, likely part of the pair we watched flying above Wingfield Basin in the evening. On that same evening, we also heard the FOY Common Nighthawk after a winter spent in South America.
With so many birds to extract and band on that day and only two of us (thanks for BPBO’s venerable “founding father”, Ted Cheskey, for spending a week volunteering), we didn’t have a lot of time to observe, which makes the 87 species detected even more so remarkable. Rain did indeed arrive on the heels of all these migrants, with intense showers on and off soon after midday. Heavy fog and drizzle settled over the land the next day, on the morning of Saturday May 20, precluding opening nets, the third day with no banding this Spring. The often-unsettled weather of a Canadian Spring means that a few to several days are always missed, often in the first half of the season: we do not open nets when it is raining or too windy, as this would not be safe for birds. On average, about 8 days are lost in a Spring season, 13 in 2017 but only one in 2010. It is likely that we will not lose too many more days this year as sunny and warm weather should now envelop us in a cozy cocoon. Or should it? Keep that toque close by!