Date: 6/8/18 6:50 pm From: Angus Wilson <oceanwanderers...> Subject: Re: [nysbirds-l] Bryant Park Northern Waterthrush etc continue
As you know from your regular visits, Bryant Park seems to have an unusual ability to hold migrants (including some scarce species e.g. Sora, Chuck-wills-widow, Prothonotary Warbler and numerous Woodcock) for long periods. I would wager, but can't prove, many of these waifs eventually die there. Remember the 2-3 chats that lingered for weeks in 2011, one eventually being found freshly dead. The rats probably make swift work of bodies so it would be hard to distinguish disappearances (moved on) from mortality. Compared to other parks, Bryant always strikes me as quite enclosed and the night sky may be masked by bright illumination, especially from the imposing Bank of America building. Does this makes it harder for migrants to escape?
All speculation of course but as you point out, migrants do seem to linger from spring into the summer (and from the fall into the winter). A test would might be to trap and band individuals and look at how long they remain and compare the periods to other urban locations like central park. The habitat doesn't strike me as right for breeding of any of the species you list, even for Catbirds it seems sub-optimal. That's why I don't think they are there by choice.
There was a panel discussion about the topic at a meeting of the Linnaean Society of New York a couple of years ago. Of all the 'pocket parks' in NYC, Bryant seems to be among the best for noteworthy birds. Some of this may be observer diligence, the scant foliage, abundant food scraps and the Patagonia Picnic table effect from birders following up on reports but I can't help wondering if the proximity and dimensions of the surrounding buildings aren't part of the equation. Recently I flew over Mid-Town Manhattan at night and noticed how Bryant Park stood out against the darker surrounding, more so than similar sized parks such as Union Square and Washington Square.
The gender inequality in the Common Yellowthroats is interesting. I wonder if local banders might have some thoughts on this? Are spring migrants through the region a 50:50 split or is the ratio unequal? Diligent field observers might even keep notes on the ratios they observe.
Angus Wilson New York City.
On Fri, Jun 8, 2018 at 7:11 PM, Joseph Wallace <joew701...> wrote: