The recent discovery of a mayfly species in southwest Wisconsin may indicate the
ecological health of the stream.
“The more species the better in terms of environmental
quality,” said Jeff Dimick, supervisor of the Aquatic
Biomonitoring Laboratory at the University of Wisconsin–Stevens Point.
The lab identified Fallceon
quilleri (Dodds), a small minnow mayfly, from a Wisconsin Department of
Natural Resources stream biomonitoring sample. The sample was collected from
the Little Platte River in Grant County. It expands the number of Wisconsin’s
known mayfly species to 158.
F. quilleri was expected to be found in Wisconsin
based on nearby records in Iowa and Illinois. Its known distribution includes
the Great Plains southwestward through Texas and possibly down into Central
America. The Wisconsin record is the farthest north and east
this mayfly species has been found.
A UW colleague in Rock County has been
watching for this species for nearly 20 years, Dimick said. Tom Klubertanz, a professor
of biological sciences, has written a book, “Mayfly Larvae of Wisconsin,” which
will be published this year. The discovery was made in time to include in this
The larval stage is used in ecological
assessments because that is the longest stage in a mayfly’s life. This species
is a nymph for about a year. It looks similar to an adult, but most adults live
only one day, after finding a mate and laying eggs to pass on their genes.
The Aquatic Biomonitoring Laboratory analyzes hundreds of stream biomonitoring samples from
the Wisconsin Department of Natural Resources and other governmental, tribal
and nonprofit agencies each year to assess water quality. Biomonitoring looks
at the variety and abundance of species present in a stream to provide clues
about the environmental quality of the sample location.
The aquatic laboratory is
affiliated with the Wisconsin Cooperative Fishery Research Unit, located at
Biomonitoring Laboratory also identified the New Zealand mud snail last October
from samples collected from Black Earth Creek in western Dane County, the first
time this tiny invasive species was found inland in the Midwest. It feeds on
phytoplankton important to fish.
“Given the state’s near-40 year history of
biomonitoring, it’s exciting to know that there are still new discoveries to be
made in Wisconsin’s streams,” Dimick said.