Brook trout spawn in the fall from September into December. 

 Lake populations usually seek out cold lake tributaries, while trout 

 already inhabiting stream or river areas spawn near their year-round 

 home or migrate varying distances in main streams or into feeder 

 streams. Populations inhabiting lakes with no cold tributaries may spawn 

 in areas of spring seepage in the lake itself or sometimes move into the 

 outlet. 



Courtship and spawning behavior includes digging of an egg pit 

 by the female for deposition of the eggs and a concurrent display of 

 courting behavior by the male. Males vie vigorously for favor by the 

 female with biting and nipping often taking spectacular form. Two male 

 trout have been observed to lock jaws and roll over and over down a 

 relatively long length of riffle area. The female digs and cleans the 4- 

 to 12-inch-deep egg pit with her tail and fins. Lying on her side, she 

 moves the broad tail fin rapidly up and down near the bottom. Bottom 

 material loosened by this process is carried downstream by current. 



During the actual spawning act, one or more males swim to the 

 side of the female in the egg pit she has dug and eggs and milt are ex- 

 truded simultaneously. Following the spawning act, the female works 

 quickly to cover the fertilized eggs by digging slightly upstream from the 

 egg pit. Newly loosened bottom material covers the eggs. 



Egg pits are constructed in bottom types ranging from fine sand 

 to coarse, uncompacted gravel and rubble. The latter is usually con- 

 sidered an ideal spawning material. Bottom or side spring seepage is 

 apparently an important factor eff'ecting choice of a spawning site by 

 brook trout. Trout in Maine waters have often been observed to ignore 

 a good rubble area in favor of a sandy area where spring seepage is 

 evident. 



Eggs hatch in 90 days at 40 F. Length of the incubation period 

 depends on water temperatures. Newly hatched sac fry, or prolarvae, 

 remain in the gravel nourished from the yolk sac. As the yolk sac is 

 absorbed, young trout become more active and work their way out of 

 the nest. 



Trout fry feed primarily on immature stages of aquatic insects. 

 Stream populations of larger fish eat aquatic and terrestial insects, 

 aquatic worms, leeches, crustaceans, and small fish. Trout inhabiting 

 lakes feed primarily on aquatic insects and other small organisms while 

 small, but become voracious fish eaters at lengths of 8 to 10 inches. 

 The most important food of large brook trout in Maine lakes is the 

 smelt. 



The brook trout takes bait or a fly readily and is quite easily caught, 

 even by inexperienced fishermen. This characteristic, combined with its 

 high aesthetic value and food qualities makes the species a fine one for 

 intensive fish management purposes. In Maine natural reproduction 

 still largely supports the brook trout fishery. In more densely populated 

 areas brook trout fisheries must be maintained by stocking with hatchery 

 fish. Pre-season or in-season stocking with large trout has generally 

 given the most satisfactory results. 



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