by Barbara Walvoord
During summer and fall, Lathrop’s human residents have been planning new residences, holding long meetings, hiring architects and contractors, flagging jurisdictional wetlands, and conferring with town land planners, all without putting a single shovel in the ground.
Meanwhile, Lathrop’s squirrel residents just went ahead and built a bunch of homes. Now that the leaves have fallen, you can see them everywhere in our trees on both campuses–dark, messy blobs against the sky.
To biologists, this mess is a “drey.” To our squirrels, it’s home.
Squirrel construction gives “stick built” a new meaning. Last summer, or early fall, our squirrel chewed off well-leafed branches before the tree told the branches to drop the leaves. So the leaves have stayed on the branches. Picking a spot about thirty feet off the ground, at a fork of two branches, our squirrel has woven these leafed branches together into a hollow ball with an opening facing a tree trunk. The attached leaves on the outside shed the rain. The inside of the ball is lined for warmth and softness with moss, leaves, pine needles, grass, and shredded bark.
The drey in my photo appears to have a hole in it, where you can see daylight. It’s not abandoned, because I have seen a squirrel going in and out. But a poorly-built drey may have been made by squirrels born this past June, inexperienced or sloppy–or both.
On nice days, squirrels leave their cozy (or sloppy) nests to feed, play, and mate. A brood will be born in January, but usually not in the drey. Tree cavities provide the babies greater safety from raccoons, provided the tree holes are less than four inches. Cavity-born infants are 40% more likely to survive than drey-born infants. So if the squirrel who made this drey is expecting babies, I hope she will have enough sense to find a good tree cavity with the right-size hole.
Fortunately for squirrels, our Lathrop woods, which once were mostly farm fields, are becoming mature forests. The early young trees have grown well beyond 30 feet and developed cavities. The oaks are taking over from early birch and sumac, providing acorns for winter food. We can expect ever more home-building at Lathrop.
I took most of the information for this column from http://www.washingtonpost.com/wp-srv/special/metro/urban-jungle/pages/121211.html
The land committee’s 20 members work well together, enjoy our land, and enthusiastically seek new members, whatever their physical capabilities–there’s lots of interesting work to do. Contact me at firstname.lastname@example.org.