Under the Road - Native Brook Trout and the Urge to Roam

“Sal, we gotta go and never stop going 'till we get there.'

'Where we going, man?'

'I don't know but we gotta go.”

- Jack Kerouac, On the Road

I don’t have to convince anyone reading this blog about the importance of wild and native brook trout conservation in Maine. What may not be so obvious is what the most important conservation initiatives we can pursue are. Some would call for stricter bag limits, others for live bait restrictions. If there is a definitive answer to that question, I don’t know it, but for heavily developed southern Maine, certainly one of the most important is watershed connectivity. Studies, including one sponsored by Sebago TU in the Swift and Dead Diamond River watersheds in New Hampshire (in the headwaters of the Magalloway River), demonstrate that some members of a brook trout population will travel throughout every inch of the watershed in the course of the year and over the span of a lifetime, if they can (see Ammonoosuc TU Chapter projects: https://www.ammotu.org/projects ).

In the spring, young of year brookies may hide from predators and heavy currents in intermittent headwater streams so small they turn to a series of puddles after spring runoff and dry up altogether in summer. In the summer heat, brook trout must travel to find cold water seeps or deep shaded pools where cooler water provides life-saving refuge. In the fall, there may be a population-wide migration up into the gravelly streambeds of upper sections of the watershed in search of suitable spawning habitat. And after spawning the larger fish may migrate down to the main stem rivers, lakes, or even salt water estuaries that provide deep, slow-moving, ice-free water for the winter. Those same fish may move back up into the cooler headwaters after ice-out in the spring. Every one of these migrations to different habitat areas may be a key to survival for a healthy brook trout population in a given watershed.

What surprises many people is the distances that these brook trout migrations and movements involve when barriers are not present. The Dead Diamond River studies, in a watershed with relatively few barriers to fish passage, showed that some fish travelled between 25 and 75 miles in the course of a year. The behavior varied greatly from individual to individual, and in different sections of the watershed. Brookies living just below Aziscohos Dam at the head of the Magalloway barely moved at all because conditions there stayed optimum year round. By contrast a small population of brook trout living in an isolated fragment of stream between two road crossings will remain weak and small, prevented from spreading and using the whole watershed, not to mention from swapping genetic material with other populations. In southern Maine, watershed fragmentation is arguably the brook trout’s biggest habitat challenge.

There are two main actions that we can take to improve watershed connectivity. The most obvious one is dam removal. Well over a thousand dams, the vast majority of which provide no hydropower or other benefits, block fish passage on Maine’s rivers and streams today. Dams also have far-reaching harmful impacts on the health of the river itself (see American Rivers’ summary of literature on the ecology of dam removal: https://www.americanrivers.org/conservation-resource/ecology-dam-removal/). Sebago TU has been involved in dam removal in the Crooked River watershed, is currently advocating for removal of the Yarmouth town dams on the Royal River, and for fish passage at Hiram Dam on the Saco. Steve Heinz, working with the Maine Council of TU, is coordinating conservationists across the state to advocate for dam removal or brook trout fish passage at hydro dams licensed by the Federal Energy Regulatory Commission (FERC). Progress may seem slow, with a few dams removed every year, but momentum is building for dam removal, and we must think of restoration in terms of the 100 to 200 plus year time horizon over which the damage was done.

The second main action that we can take to reduce watershed fragmentation is replacing road culverts. Like dams, but in much greater numbers, culverts installed with little thought to their ecological impact are often a complete barrier to brook trout migration. Even more often, they are a partial barrier, blocking brook trout movement at certain times of year and certain flow levels. Check out the Maine Stream Habitat Viewer (https://webapps2.cgis-solutions.com/MaineStreamViewer/), and search for a road crossing near you. Chances are that it is in there, and may well be a barrier to brook trout or other aquatic organisms. On critical headwater streams, culverts fragment far more brook trout habitat than dams, and they are significantly simpler and less costly to correct. Maine Audubon has developed a detailed program to encourage contractors, landowners and others to replace undersized, perched, or poorly-located culverts with open-arch culverts and other solutions to provide passage not only for brook trout but for ocean-run fish, as well as amphibians and mammals that use the stream banks as a corridor to move throughout their range (see Maine Audubon Stream Smart page: https://www.maineaudubon.org/projects/stream-smart/ ). Starting with Steve Heinz, and continuing with Robb Cotiaux, Sebago TU’s Conservation Committee has been involved in a variety of culvert replacements over the past decade. New funding from the 2018 Transportation Bond, and from USDA’s Natural Resources Conservation Service, will provide much-needed resources to correct road stream crossings in the next few years. Sebago TU should be a leader in this effort.

I hope that trout fisher men and women will take some time to become familiar with stream connectivity projects in their areas and get involved. Few things could have a bigger impact on the quality of wild and native brook trout populations in southern Maine, and indeed throughout the state. Next month, the Sebago TU Conservation Chair Robb Cotiaux will write a blog post detailing a wide range of upcoming conservation work the chapter is doing, and our strength is only as great as our volunteers’ commitment. For more information on how to volunteer with Sebago TU, contact Robb at dedbird0@gmail.com or 207-572-3057, or me (mstreeter212@gmail.com; 207-337-2611).

Matt Streeter, President of Sebago Trout Unlimited