SEA BASS FAMILY (Serranidae) 



White Perch 



Roccus americanus (Gmehn) 



Roger P. AuClair 



Regional Fishery Biologist 



White perch are more closely related to striped bass than to any 

 species of fish in our inland waters. The white perch is found along the 

 Atlantic Coast from Nova Scotia to North Carolina principally in estu- 

 aries of rivers, in brackish and freshwater ponds closely connected to 

 the sea, and completely landlocked in freshwater lakes and ponds. Re- 

 cently the range of white perch has been extended as far inland as the 

 Great Lakes. In Maine this species is found in all major river drainages, 

 in ponds that were once accessible from the sea, and has been introduced 

 by man into many lakes and ponds that were naturally inaccessible. 



Large schools of mature white perch seek a tributary stream, a 

 shallow cove, or the upper portion of a river estuary to spawn when the 

 temperature of the water is up to 60° F. This is usually during the month 

 of June in Maine. Large numbers of perch are sometimes seen milling 

 and thrashing about in shallow water. Females indiscriminately release 

 streams of minute eggs and males immediately gather round to fertilize 

 the eggs with their milt. The spawning method seems rather haphazard 

 but the eggs and especially the sperm are released in such enormous 

 numbers that there is httle chance of failure. A one-pound female will 

 release approximately 150,000 eggs at spawning time. 



The eggs have an adhesive disk so that when they sink to the bot- 

 tom they become permanently fastened to rocks, grass, or debris that 

 they chance to rest upon. Within a week, depending upon temperature 

 of the water, tiny fry, less than one-eighth of an inch long and almost 

 invisible to the naked eye, emerge from the egg. There is no parental 

 care. A sudden drop of 4 or 5 degrees in water temperature can wipe 

 out all the eggs deposited, but spawning is spread over a period of ten 

 days to two weeks and it is very unlikely that reproduction would be 

 a complete failure in any year. 



During the first two years of life young white perch feed upon small 

 crustaceans and insect larvae. Thousands of small perch one to three 

 inches long can be seined in the evening along sandy beaches where 

 they come in to feed. Young-of-the-year white perch in turn are a prin- 

 cipal food item of many game fishes including larger white perch. In 

 spring larger white perch feed mainly on insects and crustaceans but 

 during summer their diet gradually changes to include fish and toward 



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