As we’re probably all grumbling about to one degree or another, the Spring of 2019 is cold, wet, and, to put it mildly, unstable! No prolonged periods of fair weather for us or the birds so far this year! The less-than-ideal conditions make it challenging for everyone, especially birds who still need to push North and must find food and shelter along the way. These long-distance migrants need all the food they can get, in order to put on fat, which will quickly be used as the main fuel for their strenuous journey.
The cold dampens insect populations which is not good news for the insectivores, which includes pretty much all the warbler species, and the rain makes it impossible to fly long distances. That said, the many storms and unstable weather of Spring 2019 to date means that birds need to bide their time, while putting on fat as much as possible, waiting for small windows of good weather to keep on truckin’.
All these conditions amplify the boom and bust cycle of bird migration. The last we spoke, more rain was slated to arrive, and it did. It was another full day of pouring rain on May 13 when nets stayed tightly furled. The weather slightly improved for the course of the rest of the week, but conditions were frequently cold, windy, and overcast, with the occasional rain shower/storm (what’s new?). Nonetheless, migration was relatively steady from May 14 to 18, with new arrivals and a good number of captures every day: American Pipit and Common Yellowthroat on May 14; Gray Catbird, Bay-breasted Warbler, and Baltimore Oriole on the 15th; Ruby-throated Hummingbird – finally – on the 16th, though there are not many flowers for them around Cabot Head just yet, meaning they may sip sap from holes in trees in the absence of flowered offerings.
On Friday, May 17, it was cold and foggy at dawn, with a strong West wind blowing. It cleared completely during the morning and we had a good day of observing, with FOY Red-eyed Vireo, and banding, with 71 birds of 18 species, mostly warblers. It looked auspicious for the Presidents’ Birdathon planned on May 19th. Rod and Ted’s excellent birding adventures started well enough, but when they visited Cabot Head, it was to find the place mostly an avian desert. Such is the up and down of bird migration. And little did we know that another crazy day was coming…
Indeed, the strong wind in early morning of that fateful day of May 19th at first kept us in bed a little longer, but when we got up, we immediately noticed that birds were simply… everywhere! They were on the grounds, they were in the trees, they were in the air, and in HUGE numbers! When you see three male Blackburnian Warblers foraging on the ground in close quarters, when you see four (4!!) adult male Scarlet Tanagers sitting in the same tree, with a fifth in the next tree, when you see waves of birds flying overhead, you know that you’re in for a special treat.
So, I decided to open just a handful of nets to see how it would go. Coming back from opening only five nets (out of our 15), we could see that they were already filling up quickly. So quickly, in fact, that I decided not to wait the usual 30 minutes between net checks. Instead, we went to the nets right away, and right away, they were full of birds. The first net, A1, had 15 birds in it, after less than 10 minutes being open. It was the same (17 birds!) with the second net, A2, which is right next to the first one. There were already so many birds, that, while extracting birds from A2, I made another quick decision, to close all the nets! We did close A2 then, but A1 was already packed with birds again. So, we moved on to the next nets, and it was the same story. Luckily, we managed to close the third net open, A4, rapidly. And then, it was a race against time, as it took almost four hours to close the remaining three nets.
While my talented volunteers, Danielle and Scriber, were extracting as fast as they could, I was busily banding as fast as I could. As luck would have it, we had a visiting group that day, and their leader, Graham, kindly offered to scribe (that is, write down the banding data) for me. After a crash course, he was up and running and his help saved us a lot of time. I tasked others in the group with taking empty bags to the nets where extractions were being done, and bringing back bags each containing a feathered gem.
It was a fall-out of a kind I have never experienced before at Cabot Head. Because banding was so busy, even with just a few nets, we did not get to experience it fully: inside the banding lab, or concentrated at the nets, it was not possible to simply relax and enjoy the sheer magnitude of birds around us. But, numbers, despite their dryness, still can tell a powerful story. So, we ended up banding 251 birds of 28 species (including 19 species of warblers), with only five nets open from 30 minutes to four hours. The total of mistnet-hour (numbers of nets times number of hours) was a meagre 11, as compared to a potential of 90 mistnet-hours (when all 15 nets are open for the whole of 6 hours). Imagine for a second that all nets were open for the six hours and that they caught the same amount of birds as experienced, it is a mind-numbing 2,000 birds that we could have caught! It would not have been humanely possible to process all these birds humanely…
There were a few one-day records shattered again that day. We caught seven Bay-breasted Warblers, a tie with May 22, 2007. It is not a very common species banded at Cabot Head, with record totals of seven in 2010, eight in 2008, and 11 in 2002. A total of ten Blackburnian Warblers were banded, most of them bright adult males. There was more Blackburnians banded in that one day than we typically band in a whole Spring. The previous one-day high was seven in May 29, 2002, with highest seasonal totals of 11 in 2010 and 13 in 2002. All the other Springs, there were nine or fewer Blackburnian Warblers banded. During the previous fall-out day this season, we had 16 Cape May Warblers. On May 19, it was « only » 11, still more in one day than in a whole season, since the highest count for a Spring was nine in 2002. The beautiful Northern Parula kept emerging from the bags that day too, with eight birds banded. The previous one-day high was five birds on May 17, 2003. Only one to four birds are usually banded in a WHOLE Spring season, with the exception of nine birds in 2003. And, finally, the highest totals for this amazingly incredible day go to Magnolia and Nashville Warblers: 52 Magnolia Warblers were banded, compared to the previous high of 29 on May 17, 2002; and 48 Nashville Warblers were banded, compared to 26 on the previous 2019 fall-out day and 33 on May 13, 2002.
Phew!! What a day, what a day indeed! Just prior to the banding madness, a cigar with wings, aka Chimney Swift, flew by, well, swiftly; a species that can be very easy to miss and if oftentimes heard chattering overhead more than it’s observed. And the FOY Eastern Kingbird was also seen.
Suffice it to say that the 39 birds banded the following day, on May 20, under a chilly grey sky, seemed like a vacation. Will we get another spectacular fall-out day this Spring? To be continued!