Friday, May 11, 2018

The Trout are Out!


Students from Hall School's Many Rivers program first received their trout eggs at the beginning of February. They have since been watching them grow, making daily observations, and monitoring their tank environment. Students have also participated in interactive lessons to learn about trout life cycle, healthy habitats, and threats to their fish's survival in the wild.

Students traveled to Mill Brook Preserve (Westbrook, ME) on May 2nd where they were challenged to make sure this would be a great home for their trout. 

Students performed a series of water quality tests including:

pH
Brook Trout do best with a pH between 6 and 7.
Temperature
Brook Trout like it cold! They need water temperatures to be less than 65° F.
Dissolved Oxygen
Brook Trout use a lot of oxygen to breath in the water. They need more than 7 parts per million (ppm).
Macroinvertebrate assessment
Brook Trout will feed on critters that live in the water (called macroinvertebrates) when they grow a little bigger. Certain types of these critters cannot live in polluted water, so they are often used to determine if streams are clean and healthy.  

They assessed the site for:

Possible pollutants
Brook Trout need clean water to survive. Having sources of pollution near the stream could threaten the health of their habitat and the fish's chance of survival.
Ground type
Soil is Maine's #1 water pollutant. Having lots of vegetation and leaf coverage on the ground keeps soil on the land where it belongs and keeps our water clean.
Shade
Brook Trout need cold water. Having lots of shade around the stream helps to keep the water cool for them.
Water appearance
Brook Trout need clean clear water with lots of rocks and sticks to give them places to hide from predators.

At the end of their tests and observations, students unanimously decided that Mill Brook would be a great home for their trout! In a bittersweet moment, they released them into the brook with kind words and well wishes.