Monday June 18, 2012

Q:We've lived in Williamstown for 40 years and this year, for the first time, we have at least two black chipmunks in the yard. The computer says they are rare. What do you say?

DAVE AND JUDY, Williamstown

A:I agree. Over the past 40 or so years, I have only occasionally had them reported. They are seen from time to time, and several were brought to the Berkshire Museum (dead) during my tenure. One mounted specimen is in the collection. Some years ago I kept totally black specimen for several years at the Berkshire Museum. It was trapped on Holmes Road in Pittsfield and became a rather tame addition to the live-animal displays kept there. That was back in the day when I would give pet names to some of the animals kept there. This all black (even its eyes) chipmunk was called Mel (for melanistic). Melanism refers to excessive dark pigmentation in an organism, if a mammal for instance, black skin, fur, even eyes. Varying degrees occur, such as only partially black, or varying degrees of darkness.

Q:The seven baby house wrens in a nest near our yard are so tiny, but keep both Mom and Dad hunting all day. Is seven a large brood for wrens? Also I found two dead baby swallows in one box and three cracked eggs in a second. Any ideas who may have invaded this box?

TIM AND PATTI, New Lebanon

A:That number of eggs is not excessive. Wrens usually lay six to eight eggs, and sometimes as many as a dozen have been found in a nest.


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House wrens, although we think them "cute," are most likely the invaders. They are known to destroy eggs, and possibly hatchlings, in nearby nests, probably to limit competition for food. This isn't one-sided. While wren nest success was higher in areas where wrens were not associated with tree swallows, in areas where they nested near each other, it was lower. I am not sure if this is caused by tree swallow interference or is caused by other wrens.

This second letter came later from the same writer

Q:After wondering why I heard the familiar mating song from my male bluebird, I was disgusted to find feathers in a section of my lawn while mowing that belonged to my female. She was obviously attacked, probably at night, and killed. The male took on double duty and now works double time to keep the rapidly growing babies fed. Could the culprit possibly be that notorious wren? Don't the parents roost in a tree or fence at night leaving them open for attacks from owls or hawks? TIM AND PATTI, New Lebanon

A: I suspect that the female bluebird's death may have been caused by an English sparrow, a species known to kill bluebirds.

Competition is great among cavity nesters. If the bluebird was attacked by a hawk (daytime) or an owl (nighttime) I suspect all that would be left would be a few feathers.

(Although a number of animals will take advantage of a fresh kill.)

Questions and comments for Thom Smith: Email Naturewatch@live.com