These 4 videos record the Mill Brook Restoration Fisheries Sampling / Water Temperature Study Report as delivered by Steve Hurley, Southeast District Manager for Massachusetts Division of Fisheries and Wildlife, and Prudy Burt, citizen of West Tisbury, Martha’s Vineyard MA.
In this presentation, Steve goes over the history of fisheries management and sea-run brook trout in Southeastern Massachusetts. Steve presents findings from an ongoing water temperature study being conducted in Mill Brook.
Water temperatures are being recorded throughout the brook using Onset Hobo temperature monitors that record temperatures every 15 minutes over several years.
Water temperature studies are used to determine if water temperatures and the impoundments and dams that can cause temperature to rise below them are contributing to conditions harmful to native brook trout, river herring and other fish in the brook.
This temperature study was funded in part from a grant from the Edey Foundation and SRBTC donations.
Other partners working on Mill Brook include Mass Division of Ecological Restoration.
Further upstream, DER is working with Sheriff’s Meadow Foundation on replacing the culverts at Roth Woodlands.
This video was recorded on March 23, 2014 by Thomas Mayhew Productions.
Additional videos about Mill Brook Restoration are available in the West Tisbury Library and online here.
In the second video, at 16:52, Steve discusses the critical temperature requirements for brook trout.
- Brook Trout are a coldwater species
- 86 F – Instant death
- 78 F – No long term survival
- 70 F – Max temp for sustained populations
- 67 F – No growth
- 59 F – Optimal growth
- 51 F – Optimal spawning
- 33 – 53 F – Egg development
He also shows that as water temperature increases moving downstream, the percentage of brook trout found decreases, and the percentage of warm water species found increases.
Critical temperature spikes are associated with a series of approximately 10 water control structures that cause the impounded water behind them to heat up on hot summer days.