Hummingbirds begin to arrive for the season

A ruby throated hummingbird.
Photo courtesy of Learner.org

A ruby throated hummingbird.

Les Cutler of West Tisbury contacted The Times to report he saw his first hummingbird of the season Monday evening.

“I thought I saw the bird at dusk but wasn’t sure,” Mr. Cutler said in an email. “My wife, Terry, kept checking and about 20 minutes later the little guy came back to feed. Spring is here.”

Matt Pelikan, The Nature Conservancy Island’s regional ecologist and the Wild Side columnist for The Times, said the arrival of the first hummingbirds in the last week of April is a very predictable event.

Mr. Pelikan said hummingbirds winter primarily in Central America and are “trans-Gulf” migrants: they fly nonstop across the Gulf of Mexico on their way north.

While there are always a few yo-yos who get ahead of where they should be, the “front” of northbound hummingbirds generally follows, as you’d expect, warm spring weather as it moves northward, Mr. Pelikan said. In other words, their northward trip is coordinated with an increase in the availability of flowers, for example shadbush, where they can find nectar, and an upswing in the emergence of flying insects that they can also eat.

“With a metabolism like a hummingbird’s, you don’t last long if you outrun your food supply,” he said.

Lingering hummingbirds in the fall have become a much more common phenomenon on the Island in recent years. “Some of these are our usual eastern species, the ruby-throated, but western species are turning up increasingly frequently as vagrants,” Mr. Pelikan said. “An increase in the number of people maintaining hummingbird feeders is suspected to be at least part of the cause, so it’s a case in which a human activity is having a pretty clear impact on the ecology of a wild bird.”