Sixth graders discuss best places to release their salmon
The children have raised Atlantic salmon from eggs, and they’re invested in their fish’s future, said teacher Deb Barone. The time is coming to release the now “teenage” fish into a freshwater brook or stream, and the children are studying maps from the state Department of Environmental Management and debating the pros and cons of each location in the Pawcatuck River watershed.
Atlantic salmon disappeared from Rhode Island waters in the 1700s, partly because of pollution and dams built for the mills, according to the DEM. But the Lawn Avenue School’s sixth grade science class is among those hopeful the salmon will thrive here again. Someday perhaps the students can say they helped turn the tide the salmon’s way, working with the Department of Environmental Management.
Thousands of Rhode Island students already have participated in “Salmon in the Classroom,” now in its eighth year, according to Kimberly Sullivan, DEM’s aquatic resource education coordinator. Jamestown was one of the nine original schools in the Rhode Island program, which has grown every year and now reaches 30 schools, she said.
“We give them the eggs and the equipment,” Sullivan said. The department also trains the teachers and provides a bus to take the salmon into the wild.
Their salmon started as eggs about the size of a pea, according to Grace Gaynor, 12. They hatched but kept a yolk with a food supply attached to their bodies.
During class, Grace and her classmates completed a written observation of the salmon’s development. They checked to see if the salmon had eyes, a mouth and veins, for example.
“You get to see them growing and everything,” she said.
After about 12 weeks, depending on water temperatures in their tank, the salmon will drop the yolk and become salmon fry. At that point, they are able to feed on prey and the class will release them into the Pawcatuck River.
The class’s salmon are still at the Alevin stage and feed from a yolk attached to their bodies. But they are at 83 percent of their growth, Barone said.
The students calculate the progress by keeping a log of the water temperature, she said. They use a table to convert the temperatures to decimal. For example, 42 degrees equals .633 development. Then they add the numbers for every day until they get the 100 percent growth.
“It’s really interesting,” Erica Smith, 12, said. “We can look at real animals and observe them.” Sullivan said the salmon are fascinating because of the way they react to water temperature.
“The lower the water temperature, the quicker they will develop,” Sullivan said. “My hope is they will one day return to Rhode Island, but with water temperatures rising over the world, it’s going to be a little bit tricky.”
The salmon can survive in the Pawcatuck River, where they spend two years before migrating to the sea. But only two in 7,500 return from the ocean and spawn, Barone said.
During Monday’s class, Barone displayed a big map with all the past drop locations on the classroom’s interactive white board, and reminded the class that all the locations had not shown good judgment. Her map showed fish ladders, which help the salmon travel to the ocean, and it also showed dams, which will block their journey.
“The students were shocked,” she said when they saw how many salmon had been released near dams, where they would not be able to swim to the sea.
The salmon fry will spend two years in the freshwater stream before they migrate to the sea, she said.
So, the question was where in Rhode Island to release the Atlantic salmon fry, and the students debated hard.
Joshua Fisher, 11, for example, objected when classmates found a location he thought might be too close to the ocean.
“It might be brackish,” he said, meaning the salmon fry, which are freshwater fish for two years, could not thrive in salty water.
Josh thought the class should settle on a small brook near Bradford.
“Either of these branches,” he said, noting both branches had a fish ladder.
But Emma Lennon and Isabella Potter, both 12, favored a spot closer to the sea. They liked that location because of the distance from cities and pollution, which would harm the fish. They used the map’s scale to measure the tributary’s length.
“It is half a mile long,” Isabella told Josh. “How much do they need?”
“Let’s look at the big map,” Josh suggested.
“It can’t be too small,” Barone cautioned, “because predators can get at them easily.”
The teacher sent Josh to the computer to research water quality at the location he suggested.
Barone said the problem was complicated because the students do need to consider a lot of issues, such as shelter, current and food sources, as well as man-made hazards. They also will have to decide whether to lower the water temperature if the salmon are not on track to reach 100 percent growth before school ends.