Trout Brook: Year-2 E-Fishing Update...
Adam Kautza from MassWildlife, seasonal MassWildlife staff Gwen, volunteer Kevin, NFC Chair Paul Roell, and Katie from New England Aquarium.
In year-2 of what will be a multi-year top-to-bottom assessment of Trout Brook in Dover, Massachusetts, NFC worked with MassWildlife to e-fish its two most significant tributaries in hope of finding what would now be a remnant population of wild native brook trout.
Earlier efforts to locate brook trout via angling, e-fishing, and eDNA sampling focussed on mainstem Trout Brook. While multiple species of native, and nonnative, fish were encountered, we were unable to confirm the presence of wild brook trout.
One of the tributaries recently e-fished is the largest and coldest in the system. The other is notably smaller and slightly warmer, but was the last place where wild brook trout were documented in the Trout Brook watershed. Both streams are spring fed.
Water Temperatures…
The water temperature in Trout Brook at Springdale Avenue was over 77 degrees, far too hot for wild brook trout. The temperature just downstream of where a small manmade pond enters the stream was 72.5, stressful but not necessarily fatal. The temperature where the larger tributary enters Trout Brook was roughly 60 degrees which is conducive to wild brook trout.
The temperature in the largest tributary e-fished was 55 degrees, perfect for wild brook trout. The volume of water was also good, especially for this time of year. Fish densities, primarily redfin pickerel, were very strong, indicating that the stream provides important thermal refuge when the mainstem gets too hot.
The smaller tributary was in the low to mid 60’s which is conducive to wild brook trout. Unfortunately the stream went intermittent for approximately 50 yards starting 100 yards downstream of where the group began e-fishing. It resurfaced, then gained volume due to some additional water from a very small spring tributary.
An intermittent stretch of the smaller of the 2 tributaries sampled.
Interestingly, the temperature on mainstem Trout Brook 3/4 of a mile downstream of Springdale Avenue at Haven Street was roughly 70 degrees, suitable but not ideal for wild brook trout, and indicating that there are additional spring influences between the two roads. .
fish…
While there was an abundance of fish and several species of native fish in the larger tributary, including redfin pickerel, banded sunfish, and swamp darter, unfortunately, no brook trout were encountered.
Abundance was notably lower in the smaller tributary, and limited to the section downstream of the intermiitent stretch. Redfin pickerel were the only species of fish encountered. Crayfish and leeches were encountered as well.
Having been unable to confirm the presence of wild brook trout in Trout Brook both above and below Channings Pond, as well as the 2 primary tributaries, using angling, e-fishing, and eDNA, things do not look good for the native brook trout of Trout Brook…
