In a newly completed study, Dr. Marra and his students used radio transmitters to track fledgling survival in two Washington suburbs: Bethesda and my own Takoma Park. The towns are similar socioeconomically and demographically, but while much of Takoma Park is crawling with outdoor cats, many streetscapes in Bethesda are, for reasons that remain unclear, largely cat-free. At least partly as a result of this discrepancy, Dr. Marra said, fledgling survivorship among Bethesda birds is about 55 percent, similar to what you would see in a natural population. But for birds that happen to be born in my tree-lined paradisiacal hamlet, only 10 percent last long enough to take wing.
In other news, I saw a sea lion basking on a dock in Lake Washington today. In 20 years of living near the lake (and spending many an evening in a crew shell), I don't recall such a sight.