2 minute read
Audubon Joins Collaboration to Study Insect Decline
By Dr. Scott Ruhren, Senior Director of Conservation
Insects are one of the most diverse and numerous groups of animals in most ecosystems, yet their abundance, biomass and diversity have been declining worldwide. Though the effects of these troubling declines are variable, scientists believe that this loss is affecting bird and plant populations as these food webs are being stressed. Ecologists have been studying these trends for many years, but recently a growing collaboration of over 220 ecologists from 47 states and Canadian provinces was formed in North America. One goal of this partnership, the North American Insect Abundance Network, is deciphering the impacts of insect decline on aerial insectivorous birds, species that capture insects while in flight.
Audubon joined this collaboration this year, aiding in the investigation of local insect trends which adds to the global story. Two traps were deployed at Fisherville Brook and Marion Eppley Wildlife Refuges in May. An established protocol is followed to ensure that results are comparable to other North American scientists. Interestingly, the timing of insect sampling is scheduled to follow the nesting and fledgling cycles of Tree Swallows (Tachycineta bicolor), a common aerial insectivore in Audubon’s grasslands.
Collected insects are sorted by Order, identified and then weighed to determine weight per insect type. We are focusing in greater detail on flies (Diptera) because this insect group is a significant, highly nutritious part of the insectivorous birds' diet worldwide. These flies include mosquitoes and midges. Nutrient analyses of insects will then be performed by the lab of Professor Scott McWilliams, at the University of Rhode Island.
Studies like these can help tremendously in conservation as well as government policy. Through habitat protection, a steadfast commitment to reducing statewide insecticide use, and educating on wildlife issues, Audubon is trying to reverse these troubling trends in insect populations.
