This past Wednesday, members of the Lamp lab headed out once again to sample for black fly larvae from different streams across Washington County. Because our sampling this month followed storms that brought some heavy rain to the area, we were unable to sample any areas along the Potomac River, but we were able to access six more sites along nearby smaller streams. Within these streams, we once again found many larvae attached mainly to any types of vegetation within the water, as well as a couple of sites where larvae were found attached to rocks. Once water levels drop a bit within the Potomac, we will be able to return to sample several sites along the river.
We were spared the swarming of too many adult black flies by a relatively constant breeze for most of the day. The heaviest swarms of adults were to be found at the picnic area on MD-67 where we stopped for lunch, and the nearby Israel Creek, where we sampled for larvae. Here, we got the chance to test out some mosquito hats that have been sitting around in our lab for nearly a decade.
Larvae from this sampling trip will be identified to species, and then compared to the species of adult flies that are currently being collected by residents across Washington County, MD. Once the larvae and adults are identified, we should be able to infer which types of streams are acting as the source of the adult flies buzzing around people's homes across the county. As we continue to work on identifying the larvae, we will continue to post updates on the different species that are identified.