UNH Researchers Warn Of Drastic Bee Decline

PORTSMOUTH, NH - Researchers at the University of New Hampshire this week announced a drastic decline in the state's bumble bee population.

Using data from the first long-term study of New Hampshire’s bumble bee population, researchers with the New Hampshire Agricultural Experiment Station said three of the state’s most important bumble bee species have experienced drastic declines and range constriction over the last 150 years, with a fourth bee also in significant decline.

Sandra Rehan, assistant professor of biological sciences at the University of New Hampshire said
wild bees, which are highly important pollinators for both agriculture and unmanaged ecosystems, have experienced alarming declines in recent decades.

Rehan said to reverse the trend, more local scale is needed.

According to the research, scientists found drastic decline in Bombus affinis, Bombus fervidus, and Bombus terricola, as well as significant decline in Bombus vagans, with data suggesting it has been ecologically replaced by Bombus impatiens over time.

To conduct their research, scientists including Erika Tucker, USDA research fellow and a postdoctoral researcher with the experiment station; Minna Mathiasson, a graduate student in biology; and Molly Jacobson, a recent graduate of UNH’s undergraduate wildlife and conservation biology program analyzed 3,333 bumble bee specimens comprising 16 Bombus species dating to 1867.

The rusty patch bumble bee, Bombus affinis, was the first bee listed as an endangered species in the continental United States earlier this year. This species is thought to be locally extinct in New Hampshire as was last collected in 1993.

Among other species of greatest conservation need, Bombus fervidus has declined by 96 percent over the past 150 years, and Bombus terricola has declined by 71 percent. Bombus vagans has also experienced a significant decline of 42 percent in New Hampshire. The researchers suggest Bombus vagans receive future conservation consideration.

According to Rehan, this allowed researchers to track over time changes in abundance and distribution, with focus on species designated of greatest conservation need by N.H. Department of Fish and Game. Floral records also provided insight into the diet breadth of these species, which may affect their vulnerability.

“Climate and land use change may be playing significant roles in the losses of northeastern
bumble bees, with many effects still unknown with continued alterations to precipitation patterns, temperature, phenology and availability of native flora. Studies on bumble bee declines are time-sensitive and crucial to understanding how wild bees are being affected by anthropogenic changes to the planet. These data are needed so that we may prevent vulnerable pollinators from going extinct with far-reaching ramifications within ecosystems,” the researchers said.

Courtesy Photo / University of New Hampshire

UNH researcher Molly Jacobson collects samples for the recent study on bumblebees in New Hampshire.