Birds that come to bird feeders change over the seasons. Sure, that sounds obvious, but this point was driven home by recent observations at my feeder. There were six to eight American goldfinches that were regulars at my thistle feeder from October through January, but I have not seen them in the past month or so. Also, three tufted titmice and two red-breasted nuthatches used to be present daily, gorging on sunflower seed, but now are only here about once per week. This reduced number of birds is consistent with my need to fill the bird feeder about half as frequently as before.

Why do such changes occur? I think that I have at least two different flocks of chickadees coming to my feeder. Chickadees seem to be the leaders of mixed-species flocks of birds foraging in our woodlands. Both flocks visiting my feeders include white-breasted nuthatches and downy woodpeckers, but one of the flocks includes the titmice and red-breasted nuthatches, and that flock apparently does not come to my feeder as frequently as it used to. They must have found a different source of food to get them through the winter.

The absence of goldfinches is harder to explain. Vasha Brunelle reports that several goldfinches at her feeder have conjunctivitis — red swollen eyes that can cause the bird to go blind. But I have not observed this disease at my feeder in several years; I wash my feeders thoroughly twice per winter to keep it clear of disease and monthly I check to make sure that no damp moldy seed is present. My lack of goldfinches seems to be unique since others have reported that they still have their goldfinches.

In a related bit of news, the Massachusetts Audubon Society’s Wildlife Information Line sent out an announcement on March 10 about common redpolls, American goldfinches and evening grosbeaks dying at bird feeders in western Massachusetts and New York due to poisoning by Salmonella bacteria.

This is the most frequent disease of birds at bird feeders, and can spread rapidly because healthy birds will eat food that has been contaminated by the droppings of sick birds. Symptoms of this disease include diarrhea, ruffled feathers, and lethargy. This intestinal tract infection can be passed along to people who handle sick or dead birds, so please be cautious and wear disposable gloves if you are going to pick up a dead bird. The Tufts University Wildlife Clinic is interested in reports of dead birds found near feeders, and they can be reached at 508-839-7918 (and please call the Island bird hot line too at 508-627-4922.)

Bird Sightings

On a more positive note, it is amazing what strong southerly winds can do in the spring. I know it is not quite spring yet, but it is close enough for my purposes and the next two sightings will prepare us to look for unusual birds the next time we have strong southerly winds.

William Marks was working at his computer on March 10 when he happened to look out the window (thank goodness for windows — the kind you look through rather than the computer software kind, since they make computer work more palatable — I just saw a turkey vulture float over my house as I write this.) He observed a large graceful black and white hawk with a long forked tail that was drifting along with a red-tailed hawk, then it was flying in slow circles around the red-tail. The two birds were no more than 100 yards away from his window, and he watched them for about 20 seconds before he went to get his camera. Of course, the swallow-tailed kite was gone once he had a camera in his hands. Mr. Marks immediately notified the Island birding community, but nobody was able to find the bird again.

Swallow-tailed kites spend their winters in South America and breed from coastal Texas to Florida and north to South Carolina. They are known to stray into New England and Canada in the spring. Susan Whiting and Barbara Pesch’s book, Vineyard Birds II, reports that the first sighting of this species on Martha’s Vineyard was in May 1993. Usually this species is observed after strong southerly winds in April and May, with one sighting in July. Mr. Marks’s sighting becomes the seventh for the Island, and the first in the month of March. These graceful kites catch their food on the wing, usually flying insects but they will pluck lizards from trees or shrubs and they will eat snakes and small birds.

The second unusual sighting is an osprey, which was reported by two people on Chappaquiddick. Nancy Hugger reports seeing one fishing Brine’s Pond on March 9 and Jeff Komarinetz observed one at Caleb’s Pond the next day. These sightings become the earliest spring records, as the previous early record was March 14, 2002. This bird was probably blown here by those strong southerly winds we had this past weekend, so it may or may not be one of “our” birds returning to nest on the Island.

Also of note is Laurie Walker’s report of a brown thrasher along Middle Road in Chilmark on March 10. Did this bird survive our winter or was it blown here by the winds?

Spring will soon have sprung and the bird sightings will become more frequent. Please report your sightings on the bird line at 508-627-4922, and remember to leave your name and phone number. You can also listen to the message about what has been seen recently.

Robert Culbert is an ecological consultant and bird tour leader living in Vineyard Haven.