This photo shows a female brook trout on her side enlarging the redd, as she and the larger male continue spawning. Smaller female brook trout produce about 50 to 100 eggs, while larger females can produce 1,000 to 2,000 eggs. Brook trout spawn at water temperatures between about 45°F and 50°F. (Bob Michelson photo)
December 10, 2025
By Dr. Rob Neumann, Steve Quinn, Dr. Hal Schramm & Ralph Manns
Fish Life History: Spawning of Eastern Brook Trout Native eastern brook trout range from eastern Canada through northeastern Georgia. They are found in 20 additional states with sustaining populations in 14 states outside their original range. Their beautiful coloration is distinct. The back, dorsal, and caudal fins have vermiculations—wavy, wormy lines. The sides have iridescent blue spots, large yellow spots, and some small red spots circled by blue. A white bar sets off the front edge of each of the lower fins with a black stripe edging into the reddish colored fin.
Trout in the Northeast spend their adult life in cold headwater streams, large rivers, ponds, and large lakes in inland and coastal areas. Typically, they prepare to spawn in October or November. Spawning males are bright red on the stomach with a hooked jaw known as a kype. Females may be mottled with darker parr-like markings or color may remain unchanged.
Females search for shallow water with a well-aerated gravel bottom. She fans the gravel with her tail fin to create a redd, a nest-like depression in the streambed. She lays some of her eggs in this redd and males fertilize the eggs with milt. Then the female expands the redd just upstream or off to either side of the first redd. The gravel from one spawning settles downstream covering previously laid eggs. She continues the process until all of her eggs have been laid.
A newly hatched sac fry with its attached yolk sac, and below the sac fry is an “eyed-out” egg ready to hatch. INSET: As the eggs continue to develop after being deposited, the eyes and spine of the developing brook trout can be seen through the egg’s transparent shell. (Bob Michelson photos) Fertilized eggs develop just below the surface of the gravel where they are buried. About 30 days after spawning, eyes and spine of the developing trout can be seen through the shell. These eyed-eggs hatch into sac fry or alevin in another 45 to 60 days, depending on water temperatures. Using their yolk sac for nutrients, sac fry develop and grow for an additional 6 to 8 weeks in the redd.
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As the stream temperature rises, they emerge as fry in early to mid-spring. Growing fry or parr have dark vertical bars on their sides called parr marks, which camouflage the fish. Parr feed for between 0 to 3 years before they become mature adults and are able to spawn.
–Bob Michelson
TrophyCatch Catches On: From the Field Brian “BJ” Hammett caught this 15-pound 13-ounce bass in Orange Lake, Florida, on March 26, 2019. INSET: Seth Chapman fished Kingsley Lake to corral this 15-pound 11-ounce Hall of Fame bass on March 15, 2015. In 2012, the Florida Fish and Wildlife Conservation Commission initiated a TrophyCatch program, providing awards to anglers and documenting the catch and release of bass weighing at least 8 pounds. With conservation partners from the fishing industry, including Bass Pro Shops, the biggest fish of the year are awarded prizes, including a new Phoenix bass boat. It quickly gained momentum and in 2020 the program verified its 10,000th catch.
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Because bass must be photographed or filmed to document weight, biologists have used the results for biological assessments and conducted associated tagging and radio-telemetry projects. Data suggest there are 18,000 to 33,000 trophy bass (8-plus pounds) in Florida’s public waters, of which anglers annually catch from 3,000 to 6,000. Over the 12-year period, release rates have ranged from 77 to 95 percent, the release rate last year.
TrophyCatch Top-10 Waters. The Kissimmee Chain tops the list of public waters, producing 858 Lunkers (8-plus pounds), including 151 of at least 10 pounds (officially labeled “Trophies”), and a pair of “Hall of Fame” fish over 13 pounds. Famed Rodman Reservoir followed, with 737 over 8 pounds, 117 Trophies, and two Hall of Fame monsters. Though Kingsley Lake ranked sixth in total Trophy Catches, it produced no less than 17 Hall of Famers, more than twice as many as all other Florida public waters combined. A telemetry study is underway there, to provide insights on this smaller, circular lake’s secrets. For more information on the program and to sign up, check trophycatch.com .
–Steve Quinn
