I had the fortune to attend the Space Coast Bird Festival in Titusville, Florida this January and found out that there was some great gulling to be had in the area. I joined Bob Wallace and Michael Brothers along with Jan Pierson of Field Guides for a bit of birding at the Volusia County Landfill, where the sky was just full of gulls. There were big species and small species, plenty of goodies like Lesser Black-backed, a Glaucous (rare in Florida), and one Nelson's Gull. It was sure easy to see that this spot had the possibility for anything to land there, and I am sure that Bob and Michael will find some good stuff as they keep searching the site. Unfortunately we only had a morning off from the festival and did not have enough time to adequately cover this landfill. The other spot I hit was Jetty Park in Port Canaveral where I led a gull and tern identification workshop. This spot was also quite good, but with much smaller numbers of gulls, but with some interesting stuff. Thanks to Jeff Bouton, Adam Kent, and Andy Wraithmell for assissting in the Jetty Park gulling! Below are photos of several interesting birds. One of these was a possible Lesser Black-backed x Herring gull hybrid. I am interested in determining if this hybrid cross has been found before in North America, and how common it is at other sites. Cheers - Alvaro Jaramillo.
HYBRID LESSER BLACK-BACKED X HERRING
Jan. 28, 2007 - Jetty Park, Port Canaveral, Florida. I was looking at an adult Lesser Black-backed and panned a few birds to the left and noticed this gull which struck me as odd. It was clearly darker backed than the adjacent Herring Gulls, but was paler than the adult Lesser Black-backed. It was similar in size and structure to the Herring Gulls, so larger and bulkier, as well as larger-billed than the Lesser Black-backed Gull. It also had the odd feature of an orbital ring that was not red, like Lesser Black-backed, but yellowish with an orange tone. The legs were dullest yellow, almost pinkish-yellow, with obviously pinker feet. The leg colors do not come out all that well in these photos unfortunately. But comparing to the obscured Herring behind it, one can see the yellower tone to the legs. The bird was not larger than Herring so Great Black-backed x Herring was not what I immediately thought although from the photos that does seem like a possible solution to this problem as well. The fact that the legs looked to be dull yellowish, not pink, and they contrasted with clearly pink feet also suggested to me that Lesser Black-backed was the other parental species. Unfortunately I did not see the wingtips well, and do not have photos showing this feature. Jeff Bouton (Leica Optics) took some digiscopes with his superior camera, and hopefully I can get those shots from him to compare.
HERRING ? GULL
Jan 23 and 28, 2007. Jetty Park, Port Canaveral, Florida. I went to Jetty Park before the conference to take photos of some of the local gulls to use for my powerpoint presentation on gull ID, and literally the first bird I saw was the one below in the parking lot. I took a bunch of photos and noted how it was in fresh juvenile plumage and therefore likely an Arctic bird. After seeing many more local smithsonianus Herring Gulls and looking at my photos it struck me that this bird was odd looking in its Thayer's like structure, the late retention of juvenile and very nicely barred greater coverts. The only similar bird was one I photographed on the 23d, which is the second photo in this series. On the 28th I had the good fortune of stumbling upon this same bird in the parkign lot (after the gull workshop had finished!) and the whole picture clarified itself. Bird 2 was the same bird, but its left side had a more marbled look to the coverts (an older look). Also extremely odd was that the primaries on that side were broader, more rounded, also older looking! But besides these odd features, what struck me as the bird flew was how extensive the pale of the underwing was, suggestive of a Thayer's Gull. This can be seen in the flight photos below. It also had a moderate, but not extremely extensive amount of pale barring on the tail base. There seem to be various features which are odd for a classic Thayer's, odd for a Euro Herring Gull, and odd for smithonianus Herring Gull. Can anyone come up with a good explanation for this bird, or at least let me know if birds which look like this are common in your area?
This is the other side of the bird, more marbled on the coverts, rounder primary tips.
The pale underwings can be seen here, with dark on the primary tips. The inner primaries show a marbled effect at least on this side of the bird. The barring pattern on the upper and undertail coverts is more contrasting, with fewer bars than on classic smithsonianus.
Another shot, shows extent of dark on wing linings, and undertail pattern.
From above this time, tail looks much darker than from below.
Here is the extent of pale in the tail.
Another shot showing the extent of pale on underwing, which is pretty close to a typical Thayer's Gull. Any ideas on what this is?
Jan 25, 07. Volusia County Landfill, Florida. A second cycle bird. Showed paler mantle color than Herrings, also paler primaries with distinct pale fringes. Rounded primaries, pale eye, and extensive grey on the upperparts used to age the bird.