It was a snowy drive for some of the people who came this morning and it was a later start before we opened nets. The wind wasn’t too bad but we waited to see if the precipitation was going to continue with ice pellets/light snow. It was a great team of volunteers helping on our last day of fall migration monitoring! Thanks to Amy Thorne for her delicious hot apple crisp to start the day as well as a lunch from the Thorne’s to feed everyone once we were done. With the change in weather, different species were staying close to the bird feeders or eating the seed we sprinkle in the traps. The feeder nets were catching numerous birds and overall, we had a busy day handling 82 birds; so many more than anticipated with the weather.
3 Black-capped Chickadee
1 Ruby-crowned Kinglet
2 Hermit Thrush
2 American Tree Sparrow
1 Chipping Sparrow
1 Fox Sparrow
3 Song Sparrow
1 White-throated Sparrow
8 Slate-colored Junco
2 House Finch
23 American Goldfinch
ET’s: 37 spp.
The 47 birds banded by Nancy and the crew brought our season banding number up to 3,125 birds. Although certainly laudable it was only the 6th highest total going back to 2010 (when total net hours started to become more uniform due to my retirement). In fact, we were 500 birds below the average of 3,622 going back to 2010. On the plus side we banded the most species we’ve ever done – 93. And we had significantly higher numbers of a variety of vireos and warblers: Warbling and Red-eyed Vireos; Northern Parulas; Black-throated Green, Blackburnian and Bay-breasted Warblers; American Redstarts; Ovenbirds; and Common Yellowthroats. But other numbers were confusingly low; e.g., 98 Myrtle Warblers vs an average of 307; 28 Blackpoll Warblers vs 62. The picture is even more confusing when it comes to sparrows. We banded a significantly higher number of Field Sparrows (21); The 332 White-throated Sparrows banded was well above the average of 221 but we did only 7 White-crowned Sparrows (vs 27). We managed only 113 juncos (against an average of 186) but could this simply be due to a later arrival? We banded another 17 today while we were taking down the nets. But no matter how you cut it, we’re still 500 birds below average. And just think of how many times we commented to each other that the woods simply felt “empty” – that very suitable habitat was going unused.
Across the country migration monitoring stations are being asked to share and compare their results. Here’s an example of the preliminary discussion lead by Ricky Dunn:
Manomet Bird Observatory (Massachusetts) reported…..that the 2019 fall banding totals were close to the lowest in 52 years. That spurred a conversation with other northeastern U.S. banding stations, which also reported low numbers. They next sent a request for info to LPBO and Powdermill (western Pennsylvania) to see how they had done. Powdermill reported nothing unusual, but LPBO also had a low season (details not yet compiled). And incidental to other correspondence, John Woodcock, at McKellar Island Bird Observatory in Thunder Bay ON, said the following:
This was a most peculiar season at MIBO, we banded only 938 birds compared to the previous 5 year average of 2,300. We kept going to the end of the season but on most days in Oct. banding totals were less than 10. Most notably SCJU captures went from an average of 141 down to 1! Also way down were MYWA, NAWA, TEWA, WPWA, WTSP, PISI, SCJU, SWTH, BLPW, LISP, and AMRE. The weather was favorable for the most part, maybe too favorable. This year birds did not stick around much. In the past, we’ve always had a lot of repeat captures of NAWA & WTSP (for example) throughout Aug. & Sept. but not so this year. They arrived in small numbers and disappeared shortly thereafter. Diversity doesn’t seem to be impacted much though; the 5 yr avg is 67 species, this year was 63 species.
Finally, Quebec banders have also been talking about a slow season, and had a similar suggestion to John’s; that is, food supply for birds was very good and possibly migrants were making longer flights and shortening stopovers as a result. A report from Yukon also noted excellent conditions for breeding (lots of food and favourable weather), but they had “lots of birds” at banding stations this fall.
The point of this message is to ask a wider audience the same question: Did your site have a notably poor fall season? If so, was it general across all species, or mainly result of declines in a few species or groups of species?
I’ll send results of this highly informal survey back to the folks at Manomet.
So there’s plenty to think about. Is the downturn in the numbers of birds witnessed at banding station in the east due to good food availability in the north and the birds are “flying over” on their way south or….are we beginning to see the impact of the loss of nearly 2.9 billion birds recently reported in Science?