We are now only a few days away from closing the nets, taking them down, and storing them for the winter. Another season is coming to an end. It is not just the Gregorian calendar telling it so, but the ‘Bird Calendar’ is also pointing to a change. We are now witnessing the arrival of the very late migrants, the species bookending the Fall migration monitoring season.
Over Georgian Bay, we are now seeing White-winged Scoters, Common Goldeneyes and Buffleheads (both first detected on October 18), as well as Long-tailed Ducks (first detection on the 19th).
In the woods, on land and in the air, it is a suite of northern breeders. A small flock of four Snow Buntings was seen on October 21; the first of the season. This species has been detected every year, except in 2017, when monitoring ended on October 24. Typically, it is a species detected during the latter part of October: the earliest detection was October 14, in 2007, followed by detections on October 19 & 20 in 2014. However, detections in all the other years were October 23 or later.
The first American Tree Sparrow was a singular bird caught in our nets on October 22. This species shows a mixed pattern of arrival at Cabot Head each Fall: it has been detected as early as mid- to late-September in a few years, but not until mid-October in others. Most of the time, however, the initial few birds are seen during the first half of October, with the bulk of movement occurring later in the month. On October 22, the day of our first American Tree Sparrow, we were also treated to the wonderful sight of a Northern Shrike, perched prominently, albeit fleetingly, on trees near the station in the afternoon sun. It quickly flew across the basin. Northern Shrikes are never seen in any consequential numbers at Cabot Head: three birds in one day being the highest number ever recorded. It is also a late migrant, having been missed in five Fall seasons in the previous sixteen. First arrival dates have ranged from October 14 (in 2016) to October 31 (in 2008).
Also on that fateful day of October 22, we also caught a young female… Rose-breasted Grosbeak! This is definitely not a late migrant species, and it was a shock to see it in our nets. Even more, considering that it is the only Rose-breasted Grosbeak of the season. This species has never been detected in October before, with the latest bird ever being on September 26, 2008!
And finally, on October 24, in the midst of an avalanche of Black-capped Chickadees, Slate-coloured Juncos, and Pine Siskins in our nets, we got one Common Redpoll! As anyone watching their bird feeder during winter can attest, it is a species that doesn’t always visit. They like their northern, boreal quarters quite well, thank you very much. As long, of course, as there is a good seed crop. If it fails, they are content to plunge southward in large, noisy, lively flocks and bring hours of entertainment to our wintery, weary eyes! At Cabot Head, redpolls have been detected in only half of the previous Fall seasons, with first arrival ranging from October 20 in 2015 to October 31 in 2011 and daily and seasonal numbers ranging from a seasonal high of only one bird to a daily high of 159!
Other noteworthy observations: the two Bonaparte’s Gulls were seen again on October 22; one adult Greater Black-backed Gull was seen far out over Georgian Bay, the first sighting of this species at Cabot Head in the Fall since 2005! It was last seen in the Spring of 2011. And, finally, one female Red-bellied Woodpecker was observed on October 23, a regular, though not common bird, seen mostly in October.
The weather forecast for the remaining monitoring days is grey, cold, and wet! But we will keep our eyes sharp and ears attuned to the very end! October 31 will be the final day for the 2018 Fall migration monitoring season.