A Village of Spiders

“What’s in your wallet?” Not a query likely to prompt an enthusiastic response in this downbeat financial climate. But the question, “What’s in your backyard?” may set a budding naturalist off on a journey as fascinating and rewarding as an African wildlife tour. In tune with campaigns among biologists to assess animal and plant populations in specific local areas before human developments blow them away, the results may be of genuine use to science.

In the early 1990s my friend Dan Jennings offered me a challenging task. As I had taken various workshops on entomology, would I collect spiders for him along my stretch of the Maine coast? Jennings, retired as a research entomologist with the U. S. Forest Service, had embarked on a long-term study of Maine’s spiders and wanted to supplement his inland data with intensive collecting in coastal regions.

Here was an excuse for me to spend quality time in rich faunal areas, learning about a complex group of predators with a founding member of the American Arachnological Society. He and I thus set out on many pleasurable, sometimes arduous, hours ransacking swamps, forests, beaches, and islands for our quarry.  He also helped me set up a home laboratory and patiently taught me the subtleties of spider identification.

We kept at it for 15 years. One result was an in-depth portrait of the spiders and their environment in a single Maine town. There, using pitfall traps and sweep nets, and searching nooks and crannies both indoors and out, we collected almost 7,000 adult spiders. (Juveniles, which often cannot be reliably identified, didn’t count.) Our total bag was 302 species, nearly one for every four citizens of the town. Web spinners accounted for 179 species, hunters (which don’t spin webs) the remaining 123-a proportion that is very close to that estimated by the experts for all of New England. Although some bias in our collecting techniques may have slightly skewed the results, the longer-lived and usually larger females outnumbered individual males, 3,806 to 3,109. We found an even dozen non-native, invasive species, mostly near homes and other buildings. 

From the project, we amassed a ton of facts on the distribution of these arachnids through various local habitats. In 1992, within a few yards of my front door, I collected a species of sheet web spider (Linyphia triangularis) that turned out to be native to northern Europe. It had never before been reported in North America. Dan Jennings and I now find it almost everywhere we look in this area of Maine, and on a visit last summer to the Rockefeller Gardens on Mount Desert Island I noticed that it outnumbered all individuals of other spider species combined. But to our knowledge, it still hasn’t been discovered on this side of the Atlantic beyond Maine’s borders.

For anyone with an especially strong stomach for statistics and long lists of obscure scientific names, free copies of Spiders of Milbridge, Washington County, Maine (General Technical Report NRS-16) are available from USDA Forest Service, Publications Distribution, 359 Main Road, Delaware, OH 43015.