Conservation Strategies Found Within Connecticut
Fish Ladders
Anadromous fishes are species that are born in rivers, spend their adult lives in salt water, and return to freshwater streams to spawn. Salmon of the Pacific Northwest are the most commonly known anadromous species. However, Connecticut is home to a number of anadromous species that use the inland waterways as key spawning habitat. Dams and mills built along rivers stop the upstream movement of anadromous fish, thereby affecting their ability to reproduce.
Fish ladders are devices built into dams that allow anadromous fishes to continue their upstream movement by providing a corridor of water for the fish to traverse through the dam. There are many fish ladders throughout Connecticut, all of which connect anadromous species to vital spawning grounds.
Image Credit: Nilfanion, Wikimedia Commons
Thermal Refuges
Many of the larger rivers in Connecticut can exceed the acceptable thermal limit of trout species in the late summer months. When this happens, coolwater-reliant trout seek refuge at the mouth of tributaries which are connected to the large rivers. These smaller tributaries are cooler because they travel through dense, shaded forest and are often supplemented by groundwater springs.
Artificial thermal refuges are rock walls built into large rivers to extend the effective influence of cold water tributaries. The walls prevent mixing and keep the river flows separate, effectively increasing the area of the cold water plume. This, in turn, provides more suitable holdover habitat for trout. In the summer, trout can often be seen congregating in these sheltered areas by the hundreds. Of course, fishing is not allowed in these areas as the trout are already under considerable stress.
Supplemental Stocking
Some rivers in Connecticut have self-sustaining populations of sport fish maintained entirely by natural reproduction. In most cases, however, agency employees regularly supplement populations with hatchery-raised organisms. This ensures that there are enough fish available to provide outdoor recreation for a large number of anglers. The fish pictured to the left is a hybrid tiger trout.
Fish can be stocked as adults immediately ready for capture, or as juveniles that will grow in the natural environment. There are benefits to both approaches. Stocking adult fish provides a more secure return on investment, while stocking juveniles can create a population of healthy, wild fish for years to come.