What are white-winged crossbills doing in Aquinnah in September? What are white-winged crossbills? First things first: a white-winged or two barred crossbill is a member of the finch family. Although they are relatives of American goldfinches, house finches and purple finches, the crossbills are built differently.

By SUSAN B. WHITING

There are so many bird sightings this week there is no room for more. So enjoy Lanny’s photograph of a ruddy turnstone (and see it in color on mvgazette.com) and head out birding. The migration is beginning for land birds, but there are still shorebirds to delight beachgoers.

Bird Sightings:

Tara Whiting spotted an adult indigo bunting at Pond View Farm on August 10.

I may have to change the name of this column to the raptor report. Great excitement on Chappaquiddick, first the Fowle family observed four merlins on August 14. Two were immature merlins. How did they know they were immature? One merlin was being fed by the adult female and the other was begging food and fluttering its wings. So the Chappaquiddick merlins fledged at least two birds!

Laura Campbell of Rainbow Farm asked with concern about her barn swallows. For years they have had numerous pairs of barn swallows nesting in their big barn haymow. In recent years Laura said the population has dwindled — why? I checked with a few folks and found that several things might be involved.

First, house sparrows have competed for barn swallow nesting sites and won. An increase in house sparrows in the barn might be part of the problem.

An update is the first order of business. The pair of merlins that were seen on Chappaquiddick in late June and early July has caused quite a stir. The male and female were both observed by several people and reacted in a very territorial fashion.

There are three people that I consider osprey men: Rob Bierregaard, Gus Ben David and Tim Baird. On Tuesday night, Rob gave a talk about ospreys. For those of you that were unable to attend, you missed a good one. For those of you that did attend, bear with me as I review some of the new facts I learned and some old ones that were dredged up from my memory by Rob’s marvelous talk.