Post by Caroline Polgar
When Richard and Abe Miller-Rushing began investigating the
effects of climate change on the flora and fauna of New England they searched
for historical data on as many different types of organisms as they could find.
They discovered an abundance of records detailing the timing of plant flowering
and migratory bird arrival dates. Records on insect phenology, however, proved
harder to find. Several years later, Richard heard about the Massachusetts
Butterfly Club (MBC), a group of dedicated and experienced butterfly watchers.
It turned out the MBC had well maintained archives of sighting records of many
species of butterflies as reported by its members from across Massachusetts. On
the suggestion of Jeff Boettner, an entomologist at University of Massachusetts,
Richard decided to focus on elfins and hairstreaks, two genera of relatively
small butterflies native to Massachusetts. Ten species were selected for the
study, five elfins and five hairstreaks.
The research group that Richard formed (see below) was interested
not only in using the MBC records, but also in obtaining even older records of
butterfly sighting by obtaining data from butterfly specimens collected
throughout Massachusetts and currently maintained as part of the collections of
various natural history museums. After travelling the world (but mainly the
east coast of the United States) visiting museums and obtaining records, the
dataset was finally complete.
Analysis of the data produced interesting and exciting
results. Elfins and hairstreaks in Massachusetts were responding significantly
to spring temperature by emerging earlier in warmer years. On average, these
species are being seen 3.6 days earlier for each increase in temperature of
1°C. This is similar to response rates of butterflies to temperature seen in
Europe, and more importantly is fairly similar to response rates of plant
flowering and leafing, and bee sighting dates in the same region of the United
States. The change in bird arrival dates, on the other hand, are less
consistent and on average are not responding as strongly as these other
taxonomic groups. If you are interested in learning more about our research,
check out the paper, recently published in Biological
Conservation.
http://www.sciencedirect.com/science/article/pii/S0006320712005228
Research Group:
Richard Primack (Boston University)
Caroline Polgar (Boston University)
Sharon Stichter (Massachusetts Butterfly Club)
Ernest Williams (Hamilton College)
Colleen Hitchcock (Boston College)