It took Daniel Jenning several decades and 71,000 specimens to identify them.
By Joel Crabtree Photographed by Michael D. Wilson
Like many Maine basements, Daniel Jennings’s was full of spiders. But rather than hanging from rafters and hiding in corners, his spiders were neatly organized in boxes stacked on shelves, suspended in vials of alcohol. As a longtime research scientist with the U.S. Forest Service, Jennings had studied the spruce budworm and the Nantucket pine tip moth and the large aspen tortrix, but spiders were his first love. He started collecting them when he was 5 years old, while growing up in New Mexico, and he kept right on collecting after work brought him to the Penobscot Experimental Forest, in Bradley and Eddington, in the 1970s.
At the time, just one other researcher had produced an in-depth accounting of Maine spiders, focused only on Mount Desert Island. The resulting list, published in 1946, included 154 species. In 1986, Jennings went on a spider-collecting expedition to Katahdin. He found 145 species on that mountain alone, while estimating that at least 100 more likely remained undiscovered there. He also widened the search, seeking out as many spiders as possible from all 16 counties, setting traps, picking through foliage, and simply scanning the landscape. Friends and family dropped off spiders they found in their homes or while out and about. Many of the spiders lived in forests and blueberry barrens but also in potato fields and bogs and on beaches. And Jennings gathered older specimens from other researchers in government and academia too.
In all, Jennings sorted through 71,000 individual specimens — orb weavers, fishing spiders, crab spiders, jumpers, and many more. He died last summer, at age 85, just days before the Maine Forest Service published “A Checklist of Maine Spiders,” co-authored by Donahue, the culmination of his life’s obsession with spiders. In all, Jennings identified a staggering 677 species, a total that he again noted was certainly incomplete.
The checklist is a bare-bones document, a little bit of summary and a 35-page running inventory of species organized by family, but Donahue says it will, over time, tell a lot about the condition of Maine’s environment. Already, the list notes more than a dozen non-native species that have established themselves in the state, and the comings and goings of spider species, finely attuned as they are to temperature, latitude, altitude, plant hosts, and much more, can serve as an important marker to scientists tracking the ecological impacts of climate change. “There’s a lot of information you can draw once you know what was here, and how that relates to other times and places,” Donahue says. And there’s much more Maine spider research to be done, she adds, if people like Jennings put in the effort: “You can’t put a budget together and have anybody fund this kind of work — this is something that is only done by people who are passionate.”