How was the past week? Very REVI!

On August 23, rain precluded banding all morning. Clearing at the very end of the monitoring period (7 hours starting 30 minutes before sunrise) brought birds and birders outside. The latter were rewarded from the former, notably with 14 species of warblers, including three Cape May Warblers, one Northern Parula, and one Canada Warbler.

Despite a breezy East wind and overcast conditions, banding resumed on August 24 and brought a spectacular haul of 31 unbanded and 6 recaptured Red-eyed Vireos (aka REVI in the four-letter code used by banders)! Even more remarkable was the net A1 at 7:30am with 18 REVIs in it (and an additional Philadelphia Vireo for good measure). Three of these REVIs were already banded. Daily totals of banded REVIs in the fall seasons from 2002 to 2022 have exceeded 15 birds in only five days (out of 599 days with banding of Red-eyed Vireo), with the highest total reaching 19 birds on two days in fall 2005. So, basically, in one single net in one single net round, we got almost as many REVIs as the highest catch in all the previous fall seasons. The 31 birds banded that day completely smashed the previous 18-year-old record! The following day, August 25, 27 REVIs were banded, 9 recaptured, and many observed without a band. That day was very diverse both for banding and observation, with a final tally of 75 birds of 16 species banded, including 12 Black-throated Green Warblers and 8 American Redstarts (among the 11 species of warblers captured).

On August 26, a strong North wind blew slowly away the blanket of clouds covering our little patch of Earth. It was a quieter day at the nets and in the woods, with only 23 birds of nine species banded and a meagre nine REVIs. The bust of the typical boom-and-bust cycle of migration continued the next day. Under a clear sky and a decreasing East wind, very few birds were seen, heard, or caught (only four REVIs that day).

The first crisp and chilly dawn of the fall arrived on Monday, August 28, under a clear sky and no wind. Summer is inexorably waning away, as inevitable as the spinning of the Earth on a tilted axis. Without the tilt, would there be migration on Earth, depriving us of one of the best spectacles Nature has to offer? (I might be slightly biased)

Tilted and spinning it is! And with it, on that crisp morning announcing the colder weather to come, birds returned to Cabot Head, filling our nets and our hearts with joy and excitement. The REVIs once again stole the show with 18 birds being banded. A Swainson’s Thrush in the nets was the vanguard of the long-distance Catharus thrushes (the Swainson’s, the Grey-cheeked, and the Veery), who migrate through Cabot Head mostly in September on their way to the northern Andes. On that day, a Great Egret was spotted on census by Catherine: it is the fifth time with observation in the fall (last in 2018), with two more observations in the spring of 2005 and 2022. Sparse!

Warmth returned with the strong South wind on the morning of August 29. The wind required us to furl most of the nets after a few hours, as one does not want to see birds swinging wildly in a billowing net. Rain was also approaching fast and started around 11am, forcing us to close the reminding of the nets an hour earlier than normal. As a consequence, the banding total was modest, with REVI still being the most abundant, albeit with only seven birds. Many more were observed flying high and fast in the trees, with about 40 birds counted in total. 

The total for the week of August 23 – 29 is 251 birds, eight birds more than the long-standing record of 2005 for that week. Weekly totals are a good way to smooth the large daily variations in banding and allow quick comparisons between years. Of the 11 weeks of monitoring in a fall season, five have their highest total in fall 2005 (up to now) and four in 2022, these years – not surprisingly – having the second and highest banding totals overall, respectively.

As it is, the current banding total for REVI this season stands at 145 birds, which is already the second highest total ever. And there is still a good two weeks of movement through Cabot Head for this species. The record is 239 REVIs, established in the fall of 2005 when an abundant crop of chokecherry seemed to have enticed this species to spend a lot of time at Cabot Head. Will this other 18-year-old record finally fall? The game is on!