Florence and Pole Farm: Jan 20th, 21st

While waiting for FedEx Ground to screw up a delivery I birded Florence (NJ) and the Mercer County Park NorthWest (i.e. Pole Farm).

At Florence I arrived to find a lot of ice on the Delaware River at the boat ramp park. This stretch of river heads east-west and of course such is the curse of Florence that the river view overlooks the large Tullytown landfill on the Pennsylvania side. The upside, of course, is that landfills attract a ton of gulls and many of these loaf on the river.

The moment I arrived at the boat ramp park a Great Cormorant flew by and helpfully circled back around to help me clinch the ID - it was starting to molt into breeding plumage so the white flank patch was partially formed. There were quite a few Common Mergansers on the river - probably frozen out further north and from interior lakes. But the main deal is the gulls, many thousands of them, most of them Herring and Ring-billed: there were relatively few Lesser Black-backed Gulls, perhaps less than 10 seen on the entire trip, but I found a pale immature Iceland Gull on the second pass through the flock, and then a second one that kept flying around that was a little darker - towards pale coffee color. After scanning the flock multiple times I went west (i.e. downstream) a few blocks to River's Edge Park where there were very few gulls but luck produced a fly-over third Iceland Gull.

Back at the boat ramp the gull flock had taken flight and moved upstream, so I went to neighboring Roebling and at the park along Riverside Ave I scoped through the chain link fence at the more distant gull flock, (re-)finding two Iceland Gulls and Lesser Black-backed but no Glaucous. I hadn't birded Roebling before but in line with the whole Florence experience the park there overlooked an EPA Super Fund site along the river and seemed to be next to an abandoned manufacturing center. The dilettante nature of birding seems somewhat at odds with the gritty nature of these two towns.

Back at Pole Farm in Lawrenceville a mid afternoon visit yielded the usual suspects: Northern Harrier (2 females, at least one of which was immature), Red-tailed Hawk, a female American Kestrel, American Tree Sparrow and a Short-eared Owl that put in an appearance at a relatively early 3:30pm. Around that time two Eastern Meadowlarks zoomed overhead. Lets hope all these species can hang on for the snow thawing toward the end of the week.

The following morning at Pole Farm I pulled up to find a hovering Red-tailed Hawk, then panned to what I thought was another one before realizing that it was a pale morph Rough-legged Hawk. Possibly the same one that has been in the area for several weeks. I watched this bird for a while as it hunted the field, catching at least one rodent, before it circled high into the air and headed north. I suspect these Rough-legged Hawks cover quite a lot of territory in one day, whereas the Harriers (1 male, 1 female on this visit) seem to cover more limited ground.

(Thursday 22nd: both pale morph and dark morph Rough-legged Hawks were at Pole Farm, with the dark morph showing some aggression toward the light morph. Also there was the female American Kestrel, a single Northern Harrier, Red-tailed Hawk, Dark-eyed Junco and American Tree Sparrow. The Kestrel showed signs of food caching, something I hadn't observed before.)

(Friday 23rd: one apparent male pale morph Rough-legged seen well at Pole Farm, with what appeared to be a second adult female pale morph seen just before I left - it appeared different with a solid black breast band but was only seen at a distance)