Over 50 people turned out to hear Michael Hopper, president of the Sea Run Brook Trout Coalition, talk about the successes and lessons learned from stream restoration efforts at Red Brook in Wareham, and the Quashnet River in Falmouth, and how those could be considered in the discussion about our own Mill Pond/Mill Brook. The program was taped by MVTV and will air daily for the next three weeks. Additionally, a DVD of Michael’s presentation is in circulation at the West Tisbury Library.
It is important to correct a few points:
• The native fish species that was the subject of the discussion is the eastern brook trout (Salvelinus fontinalis), also known as sea run brook trout, or salters, not the brown trout mentioned in the Gazette article. The brown trout (Salmo trutta) is an introduced species from Europe that frequently outcompetes salters in their native habitat. Previously known to flourish in over 70 streams in eastern Massachusetts, salters are now known to inhabit just nine of those streams.
• A point stressed repeatedly by Michael Hopper throughout his presentation was that there is no data that shows that salters can or will use fish passage ladders, as suggested by a member of the Mill Pond committee. Additionally, a fish ladder will only put these cold water fish into a warm water habitat where they will neither survive nor thrive. A fish ladder will not address their other habitat requirements of cold, clean, moving, well-oxygenated water, and a stream bed of gravelly substrate which they need to spawn. Water temperatures as high as 86 degrees have been recorded at the outlet of the Mill Pond by the caretaker of the Mill Pond dam, Kent Healy. Trout don’t survive in temperatures much higher than 70 degrees.
• The estimated costs for the three dredging plans, developed by the Mill Pond committee with their consultant, range from $150,000 to $700,000. The plan currently favored by the committee which features a constructed wetland in the north half of the pond, has a price tag of between $355,000 to $405,000. Half this cost might be funded through the state’s 319 grant program, the remainder paid for by the town. Alternatively, 100 per cent of the costs associated with the one-time action of stream restoration at the Mill Pond would be paid for through grants from groups such as National Oceanic and Atmospheric Administration (NOAA), American Rivers, Trout Unlimited and the state Division of Ecological Restoration. Sea run brook trout are considered a NOAA Trust Resource species which is one of the many reasons this project is unusually appropriate for federal funding. Should the town choose to restore the unimpeded flow of the Mill Brook, we would work with the Division of Ecological Restoration to put the Mill Pond on their list of priority projects, which would qualify us for grant funding.
As the last of the six manmade ponds on the Mill Brook before it flows into Tisbury Great Pond, Mill Pond is an extremely important link in the habitat of our native salter brook trout. A key part in the life cycle of the salter brook trout is being able to get down to the salt water habitat of Tisbury Great Pond, one half mile to the south of the Mill Pond. There, they feed and grow significantly over the season, coming back up into the Mill Brook to shelter from the warm water of Tisbury Great Pond and to find suitable habitat in which to spawn. Stream restoration also provides improved habitat and connectivity for American eel, the brook lamprey and river herring, all of which are also considered NOAA Trust Resource species. While most of these species are not directly of interest to fishermen, numbers of these and other valuable forage species would increase considerably which would help attract species of interest to fishermen, like striped bass, bluefish and fluke. Increased forage species would also support other species of interest such as river otter, osprey and great blue heron.
While some may see stream restoration as a controversial option, it is a viable alternative, and one that many communities have chosen to deal with their obsolete dams and manmade impoundments. Not many of these dam removal projects have been big, or dramatic; many of the dams removed were no bigger than the sluiceway on our own Mill Pond, yet the benefits to water quality and fish connectivity have been significant, not to mention removing the costs of maintenance and liability to the towns — forever.
It has been well over 100 years since the Mill Pond has been used for its original purpose, which was to power the mill located on the south side of Edgartown Road. Today, ecologists understand the detrimental effects that these dams and their resulting impoundments have on water temperature, creating barriers, both thermal and physical, to fish passage, and sediment accumulation. More importantly, town officials are learning there are significant costs associated with dams and impoundments, and that stream restoration is one of the ways to reduce these costs and can absolutely benefit the environment and the townspeople.
Currently, from all of the data gathered on the Mill Pond in the last 10 years, the only thing that can be said with any accuracy is that the Mill Pond is a bit shallow in parts and warm. According to the Mill Pond committee’s own consultant, the rate of sedimentation is about one sixteenth of an inch per year. There are no major water quality issues, there are no big stands of invasive vegetation, and no need to rush into any big decisions to spend huge amounts of money on a problem that doesn’t exist.
Please, let’s consider all of our options carefully.
Prudy Burt lives in West Tisbury and is a member of the town conservation commission.