Maine Butterfly Survey

Rather than writing on birds in today’s column, I’ll devote this space to another group of winged creatures, the butterflies. In particular, I want to announce the start of a five-year project to produce an atlas of the butterflies of Maine. The project is called the Maine Butterfly Survey (MBS). See the website at http://mbs.umf.maine.edu/. The MBS will rely heavily on volunteers throughout the state.

Despite the fact that butterflies are conspicuous in our gardens and fields, our knowledge of the distribution of butterflies throughout the state is fragmentary. In preparation for this atlas project, Phillip deMaynadier, a wildlife biologist at Maine Inland Fisheries and Wildlife, and Reggie Webster, a Canadian expert on the taxonomy of butterflies, searched the literature, museums and private collections for records of Maine butterflies. They found nearly 9,000 records, providing a baseline for the atlas project.

Their report, available in pdf format at the MBS website, provides township-level maps for the 114 species of butterflies in the state as well as detailed information on rare species in the state. The map of the distribution of the Monarch butterfly, an easily identified species, shows how much of the state needs to be sampled.

The Maine Butterfly Survey (MBS) follows on the heels of other butterfly atlas projects in New England and maritime Canada. Connecticut, Massachusetts and New Brunswick have recently completed atlases and Vermont is in its final year of such a survey. The coordinators of the MBS are Phillip and Reggie as well as Ron Butler of the University of Maine-Farmington and me.

Butterflies are a worthy subject for study because they contribute a colorful and conspicuous component to our state’s biological diversity. Butterflies play an important role in terrestrial and wetland ecosystems by serving both as pollinators of many wildflowers and prey (both caterpillars and adults) to larger species ranging from dragonflies to birds. Butterflies are also widely recognized for their value as ecological indicators of ecosystem stress due to such factors as climate change, pollution, and habitat loss. Without thorough baseline knowledge of the distribution and relative abundance of butterflies, it is impossible to gauge the magnitude and direction of population changes in the future to a variety of environmental variables.

The MBS will use the townships as the sampling unit. There are 711 townships in the state of Maine, most of which are roughly the same size. To document the presence of a species in a township, a voucher must be submitted. The voucher can be a specimen that is collected with a net and then submitted as a preserved specimen to the MBS for confirmation of the species.

Although there is no evidence that collecting has every led to the demise of a butterfly population, some people are reluctant to kill a butterfly in the name of science. Two other types of vouchers are acceptable for the MBS that do not depend on the collection of butterflies. Close-up digital photographs or print photographs are acceptable as vouchers. Also, road-killed specimens collected from road shoulders are acceptable vouchers as well. The number of butterflies killed by automobiles is appallingly high.

Voucher specimens are needed for any butterfly atlas so that scientists can independently verify the identifications. Sight records may be wrong and cannot be independently verified after the fact. The taxonomy of butterflies is unsettled for some species. Future taxonomists may find great value in the vouchers provided by the MBS.

I hope that you will consider becoming a volunteer for the MBS. You can contribute as few or as many vouchers as your time allows. Sampling areas are not assigned so you can sample anywhere throughout the state.

We ask that every prospective volunteer attend one of our workshops to learn the details of voucher preparation, collecting techniques and preparation of the data forms that must accompany your vouchers. Every workshop participant (eighteen years of age or older) will be given a collecting net, a specimen jar and glassine envelopes for storage of your vouchers.

The next workshop will be held on Saturday, July 14 at the Delta Institute of Natural History in Bowdoin from 9:30 AM until 3:30 PM. You’ll hear a lecture on butterfly biology and identification from me as well as instructions on data collection and butterfly netting from Ron and Phillip. If the weather is fine, we will spend part of the afternoon in the field. Please contact me soon via email to reserve a spot at the workshop; the limit is 30 people. I hope to see you in Bowdoin.

[Originally published on May 19, 2007)