News  Trout spawning underway

MassWildlife stocked over 63,000 trout into Massachusetts waterbodies this fall. (Go to mass.gov/trout to see where fish were stocked.) While fall stocking has concluded, hatchery staff are hard at work preparing fish for the years ahead!

MassWildlife operates five fish hatcheries in the state, located in Sandwich, Belchertown, Montague, Sunderland, and Palmer. Each fall, hatchery staff manually spawn trout at Palmer and Sandwich hatcheries to produce more than 1.5 million fertile brook trout, brown trout, and tiger trout eggs.

Spawning happens when hatchery staff carefully mix trout eggs and milt together. The process begins when eggs are gently squeezed from a female and collected in a bowl. Milt from a male is then squeezed into the same bowl and a small amount of water is added to activate the sperm. Male and female fish are quickly returned to the water to minimize stress.

The mixture is gently stirred to encourage fertilization. The eggs are placed in a bath containing a mixture of water and a special buffered iodine-based disinfectant. This process reduces the risk of disease and allows the eggs to absorb water and become fully formed and firm, a process called water hardening. The water-hardened eggs are then counted and placed in incubation troughs where they remain until they hatch. These million and a half eggs, coupled with rainbow trout eggs obtained through a cooperative program with the US Fish and Wildlife Service, will be reared at MassWildlife's five hatcheries.

After incubating for about two months, the eggs hatch into fry (pictured above). When they are about two inches long, the fry are moved from the indoor “hatch house” to outdoor rearing pools. The fish grow in these pools for 1.5–2.5 years until they reach stocking size. Depending on the species, trout are stocked when they are between 12–14 inches long.

Trout are stocked in hundreds of rivers, streams, lakes, and ponds throughout the Commonwealth every spring and fall. Learn how to identify and catch the different types of trout that MassWildlife stocks.