Wednesday, April 20, 2011

"It's not a Boat-Tailed," writes Tom Fiore and another PS

Boat-Tailed Grackle at The Harlem Meer - 4/9/11
Photo by JANE F. ROSS


Common Grackle in Central Park - 4/18/11
Photo by MURRAY HEAD



Tom Fiore writes:

Marie,

In looking at the photos by Murray Head that you added to your latest nature notes blog entry, this is not a Boat-tailed, but a male Common Grackle. Several things are visible from the photos (yes, that one shows attitude but as we also know, many members of the icteridae [blackbird family] show aggressive posturing and behavior at times - see your nearest male Red-winged Blackbird around a nest-site, for proof of that and try wearing a red scarf over a black shirt if you want even more of a reaction!) - in the middle photo, especially, it is clear that there is a strong demarcation in plumage color from the head, to the back, and also that the iridescent colors on the back are, to borrow from David Sibley's full-sized field guide, "variegated, multicolored" which may be more apparent if the photo is made a bit larger on one's computer monitor screen; the bill is not quite heavy as would be on a Boat-tailed Grackle, nor is the tail long enough in relative view compared with the overall body length as seen in all 3 of the photos by Murray Head. Going back to Jane Ross's photos of the male Boat-tailed Grackle at the Meer on April 9th, one can see in her photos that the tail is proportionately much longer relative to the entire bird, the bill is a bit heavier, and the iridescent color of the back merges closely with the head color as well as being of a more evenly bluish-green. There well could be more Boat-tailed Grackles that will appear in Central Park (or have already) and it is a species which could escape detection at times, as not all, even amongst a park so thoroughly observed by naturalists, will take notice of every grackle they come across there. For now, I believe Jane Ross's photos represent the first and (so far) only fully-documented occurrence of Boat-tailed Grackle for Central Park. Incidentally, on the subject of (larger) grackles, a species to keep in mind is Great-tailed Grackle which has the potential to stray as far as NY. That species has spread greatly over the last century and is still doing so to some extent. A male Great-tailed Grackle at a length about half-again larger than a Common Grackle would be rather apparent in a first look. Great-tailed females and perhaps males also could be visually mistaken for Boat-tailed Grackle.

On the migration front, a fair number of arrivals these past few days and today, Wed.
4/20, there are so far at least a few "new" as well as lingering migrants - this is sent well before a better tally of the day's sightings is apparent. There are migrant birds in much of the park and all over our region now... I just spent 2 hours at Summit Rock, and found no reason to leave that spot - now to see what other areas may offer in bird-life. As I wrote to the NYS bird list, the female Varied Thrush and Red-headed Woodpecker (now with bright red hood) both continue in their respective areas, the thrush south of the Met.; woodpecker south of Sheep Meadow.

Best,
Tom

PS from Marie: Today, Tomorrow and Friday I'll be answering questions about Red-tailed Hawks in the city on the New York Times blog http://cityroom.blogs.nytimes.com/.

Tuesday, April 19, 2011

Is it the same bird? and a PS

On April 9th Jane Ross [http://rossbirds.blogspot.com] reported the first Boat-tailed Grackle ever to be documented in Central Park. I posted her report and photograph of the bird at the Harlem Meer on the next day. Yesterday 4/18/11, photographer Murray Head wrote:

I'm thinking this might be one...
He has the tail... and the attitude (last image)

At the reservoir - South East corner

Also atthe reservoir... about a dozen Ruddys, and the Common Loon,
who was too far off to get a decent photo of.



Three photos by Murray Head -- 4/18/11


PS This week on the New York Times website City Room I'll be answering questions about a pair of Red-tailed hawks now nesting on a window ledge at NYU. [They've been dubbed Violet and Bobby]. You can observe the incubating hawks via a live-stream webcam, and send in more questions. I'll try to answer as many as I can!