One of the most common bees in Vermont as late as the 1990s appears to have been eradicated from the state, but a University of Vermont researcher has provided the federal government with data that could prove critical to the bee's recovery.
That bee, commonly known as the rusty patched bumble bee, and known to scientists as bombus affinis, is being considered for federal protection through the Endangered Species Act, thanks to work by UVM postdoctoral research assistant Leif Richardson.
The U.S. Fish and Wildlife Service on Wednesday proposed listing the rusty patched bumble bee as an endangered species. Although scientists say the insect's decline has been precipitous and well-documented, the exact cause remains uncertain.
In its report, the Fish and Wildlife Service says the data for its analysis came primarily from Richardson's work.
A co-author of a North American bee identification guide, Richardson said he collected thousands of records of bee observation in the course of writing the book. This data constitutes all but a few hundred of the observation records on which the Fish and Wildlife Service relied in determining the species may need further protection, Richardson said.
An ecologist who studies bee declines and the relationship between flowers and bees, Richardson said he collects thousands of bees every summer and caught one of Vermont's last known rusty patched bumble bees.
He found it in Huntington in 1999, one of two bombus affinis specimens seen in Vermont that year, Richardson said.
"I've looked for it every year thereafter," he said. "I collect thousands (of bees) every summer. It was never seen again."
The Vermont Center for Ecostudies collected more than 10,000 Vermont bees in 2012 and 2013 to survey extant species, and researchers involved in the project found not a single bombus affinis. These researchers searched "nearly every town, every county, every eco-region" in Vermont and found "exactly zero" bombus affinis, Richardson said, "which strongly suggests it's gone from Vermont."
Rusty patched bumble bee populations have fallen precipitously across the species' historical range, and not just in Vermont, Richardson said.
As late as the 1990s, when bombus affinis was still one of the most common bee species in Vermont, it was found throughout 28 states and one Canadian province, Richardson said. In the last five years, the bees have disappeared from seven of those states, and in that time only solitary bees have been observed in all but three or four of the remaining states.
"I think the evidence is very clear that this is a case where that law should be brought into play and can actually help preserve a species that's declining and in danger of extinction," Richardson said.
The bee could fall under endangered species protection within a year, Richardson said, and the Fish and Wildlife Service is soliciting public comments on the proposed listing until Nov. 21.
About 10 percent of the value of America's agriculture results from pollination, Richardson said, and protection for the rusty patched bumble bee could go a long way toward preserving other important pollinators.
Vermont legislators, in response to widely publicized die-offs among this and other pollinators in the state, formed a pollinator protection committee this year, and members met for the first time at the Statehouse this month.
Richardson said it's not yet clear what must be done to address the problem, but said it's important to preserve bombus affinis and other pollinators not just because of their intrinsic value, but because of their utility to humans.
Across the globe, 75 percent of crops depend on pollinators, he said. Of the total value of American agriculture, 10 percent results from pollinators, he said.
"This is a substantial economic issue," Richardson said.
"When we lose these wild species, it's concerning to ecosystem health, or ecosystem function, but it's also (worrying) for reasons having to do with human food supply," he said.
If bombus affinis gets federal protection, he said, the economic impact could go in several directions.
"The conservative estimate is, we've actually suffered financial cost from the loss of these species," due to its role in agriculture, Richardson said.
But in some parts of the bee's range, farmers and others might have to apply fewer pesticides, and in particular those belonging to a class called neonicotinoids. Municipalities and other governments will need to consider the endangered species before making land use changes. And, Richardson said, grant funding might get allocated preferentially to bombus affinis and away from other topics of research.
"Overall, I don't think listing of the rusty patched bumble bee will cause a significant financial burden to anyone, and it could actually net us a return in financial terms from the recovery of this species because it's so important to agriculture," Richardson said.
It's not clear that listing them as endangered species will bring rusty patched bumble bees back to Vermont, Richardson said, but it's possible, and the bee's not likely to come back without it. Protecting bombus affinis could protect other species too, he said.
"I thinking listing this species could help at the state level to preserve pollinators in general," Richardson said. "It might be a good umbrella for other" species at risk.
Vermonters can encourage bumble bee preservation by planting flowers or vegetables and by avoiding pesticides, and neonicotinoids in particular, Richardson said.
More broadly, bee recovery is encouraged by preservation of Vermont's natural ecosystem and its old farm fields and low-intensity agriculture.
There's "convincing evidence" that climate change is harming bee populations as well, Richardson said, "so if you're concerned about bees do what you can to influence policy to prevent the accumulation of greenhouse gases in the atmosphere."