News & Notes

Coldwater Fish in the Summer Heat

Wednesday, July 22nd, 2015
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brook-troutIt was one of those infernally hot summer days, when the air anywhere away from the coast was stifling. I didn’t really want to get into the car, but I convinced myself to take a short drive for the chance to ward off the heat by standing in a well-shaded stream.

After rigging up a fly rod and clambering down the steep bank that descends from the bridge abutment, I stepped into the water.  I couldn’t help but notice how cold it was — maybe 40 degrees less than the air temperature. So maybe this was a good idea, I began to think.

I made a cast upstream, aiming for the crease between two rocks, where a small spout of water flattened out and settled into the run. The fly had barely landed when a head poked above the surface and snatched it. Up went the rod tip to set the hook, and a minute later I unhooked the small wild brook trout and slid it gently back into the water. Within the next ten minutes, almost in the same sequence, the scene twice repeated itself.

As I began to move toward another run, I noticed how badly degraded the stream channel was: lots of muddy sediment piled up in the low-water recesses along the bends in the bank, and long reaches of scoured-out clay, slippery as ice and offering not the least bit of cover. Strange to find wild brook trout in a place this trashed, I murmured to myself; it must be the cold water.

Western Maine, although cursed with miles of gouged-out stream channels, is blessed with abundant groundwater resources. The water in the stream I fished comes right out of the same aquifer that supplies one of Poland Spring’s bottling plants, and throughout Cumberland, Oxford and Franklin counties are scores of other streams with abundant groundwater to cool them in the summer months. No wonder the climate scientists have modeled Western Maine as the last refuge for native brook trout in a “hot,” end-of-century climate change scenario.

My afternoon foray got me thinking about the potential for restoring native brook trout in the region’s streams.  If you ask the fishery scientists about restoring Maine’s brook trout, they’ll gladly point out that restoration is really a secondary concern in a state that still contains more native brook trout habitat than any place in the US.  They’re right, of course, but the habitat they’re referring to is mostly in ponds. What about the streams that still have lots of cold water and are the ecological cornerstone for native wildlife throughout the region?

Maine Audubon is already on the case when it comes to stream restoration. We’ve led the effort to make streams behave like they were supposed to, by working with municipal highway departments to replace non-functioning culverts with StreamSmart road crossings. But there’s a lot more we can do. We’ve worked hard to survey native brook trout waters throughout Maine, and brook trout figure prominently in our new strategic plan, as an iconic species that can help leverage landscape-scale restoration.  We’ll have more to say on this subject, so look to future installments of my blog for further details.

- Charles

Charles Gauvin, Executive Director

Charles Gauvin, Executive Director

Charles Gauvin started at Maine Audubon in 2014. Gauvin brings more than 25 years of experience in conservation leadership, much of it as the president and CEO of Trout Unlimited, the nation’s leading river and fish conservation organization.Gauvin most recently served as Chief Development Officer at the Carnegie Endowment for International Peace in Washington, DC. He collaborated with Carnegie scholars worldwide to develop program strategies and support in the United States, Europe, Russia, the Middle East, Asia and South Asia.