Spring migration is just heating up around here so I’ve been stealing odd hours in the nearest stretch of decent habitat. Riverdale Park is a thin ribbon of greenspace along the steep northwestern border of New York City. I’ve never found this park to host a truly impressive array of birds; the sightlines are poor and no matter what time of day I visit, the canopy seems backlit. But during this gray weekend, the tiny silhouettes of birds flitting from treetop to treetop or streaming north overhead evoked the image of a river of migrants flowing abundantly towards the mighty boreal.

Common Yellowthroat

We tend to judge spring birding by the number of warbler species encountered. By that measure, Riverdale Park represents well enough. Yellow, Yellow-rumped, Black-and-white, Black-throated Green, Black-throated Blue, Palm, Northern Parula, Common Yellowthroat, and Ovenbird were evident, most in excellent numbers. I believe at least half of this species breed in the park. In fact, the Black-throated Blue, brilliant in breeding plumage, may well be the same courting buck I’ve encountered here in the past; he did occupy the same tree and was equally brazen.

Stunning Scarlet Tanagers and Baltimore Orioles also made the scene here, as did a bevy of typical Bronx birds. Species I was surprised to spot included Veery and Swamp Sparrow, and while I did anticipate Great Crested Flycatcher, I hardly expected that many! Throw in abundant Blue-headed and Warbling Vireos and you’ve got some splendid seasonal birding. Ah, Spring.

Great-crested Flycatcher in flight