Chasing butterflies for science

Posted by

A friend told me yesterday of a research project she was part of while working in the US. The project looked at the behaviour of a particular wetlands butterfly, Satyrodes appalachia (Appalachian brown), in habitats unlike their own, and was intended as a study of how animals may disperse through unconnected habitat fragments.

(If you’re interested, you can find the paper here: The conflicting role of matrix habitats as conduits and barriers for dispersal).

The fun came in the method used to obtain the data. First, individual butterflies were captured in their own swampy habitat (okay, that’s not the fun part). They were then transported to the new site and released, using the Butterfly Release Device (BRD), which allowed their release without the presence of the researchers. The butterflies then fluttered off, often at speed, followed by one researcher at a safe distance, while the other researcher, armed with a stopwatch, called “Mark” at 5-second intervals, at which the follower dropped a small bean bag. Once the butterfly stopped for at least 30 minutes or flew out of sight, the flight was considered over and the path was then recorded.

Now according to my informant, chasing after butterflies flitting hither and yon and dropping bean bags was funny enough, but add in the fact that this was happening on Fort Bragg military base, and you get to the height of absurdity: imagine doing all that while bombs go off, helicopters roar overhead, and guns fire at various shooting ranges nearby.

Why Fort Bragg, I hear you ask? Well, military bases in the US are often havens of intact remnant vegetation, and thus often provide habitat for a variety of rare species. In fact, that location is the only habitat for the very rare St Francis’ satyr butterfly, for which the Appalachian brown was a surrogate in this study. These butterflies live only on beaver meadows, which are the water meadows left after beavers have dammed a creek or river on low flat ground, then left, leaving the dam to disintegrate and the water to spread and gradually seep into the ground (hence the swampy search).

(In another aside, you can find some fascinating information about the benefits of the beaver dam life cycle on this page – they do everything from cleaning the water, to flood mitigation, to providing beneficial habitat for a variety of rare and common species).

The aim of all this was to see how animals, in this case butterflies, could disperse through different habitat, as that has implications for how well a given species can survive fragmentation of their chosen habitat. This is of prime importance, since the patches of natural habitat are often small and fragmented, so if we want to save some threatened species, we need to know whether they can transit the ‘badlands’ between the patches of natural habitat.

So, if you thought a career in science was all about reading boring journals and performing endless experiments and analysing data until your eyes dropped out, think again – you may get to chase butterflies through a field while things explode around you.

[Featured image: Satyrodes appalachia. Image #1115080 at Forestry Images, licensed under Creative Commons.]

Leave a Comment

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s