Staff and volunteers from Connecticut\u2019s Beardsley Zoo joined state workers Wednesday to try to rescue thousands of fish stranded in a section of the Pequonnock River near the zoo in Bridgeport. The lack of rain this spring has created low water levels, making it impossible for the fish \u2014 up to 18,000 of them, according to estimates \u2014 to migrate up the Pequonnock River and over the dam into Bunnells Pond. Staff from the Connecticut Department of Energy and Environmental Protection, joined by the zoo employees and volunteers, worked to rescue as many fish as possible during an operation that was expected to last up to two hours. They were expected to use nets to capture and carry the fish over the impairment, releasing them into deeper water so that they may continue their migration. The goal was to rescue up to 3,000 fish during the first day of the effort. The rescue effort can only last for 90 to 120 minutes per day because human activity in the river agitates the fish, causing them to experience life threatening stress. \u2018Fish ladder\u2019 at the site Each year, alewives and blueback herrings migrate between fresh water and salt water in order to breed, hatch, and live. Due to the height of the dam connecting Bunnells Pond and the Pequonnock River, a "fish ladder" was constructed to aid the annual migration. The fish ladder allows the fish to bypass the dam by "climbing" over the height of dam. It is believed to be the highest fish ladder in the Northeast. Zoo\u2019s conservation mission Conservation is an important part of the mission of Connecticut\u2019s Beardsley Zoo, and these fish are vital to both the health of the Pequonnock River and to its food chain. Their presence has spurred the re-population of osprey, large bass, black-crown night herons, and otters in the river. This is the second year in a row that the zoo has supported a rescue effort for the fish. About the pond and river The 33-acre Bunnells Pond is in Beardsley Park and visible from the Route 8\/25 connector. It is formed by a dam on the Pequonnock River, near the Wonderland of Ice skating facility. The Pequonnock River begins in Monroe and goes through Trumbull and Bridgeport before emptying into Long Island Sound in downtown Bridgeport.