FAMILY CENTRARCHIDAE 



243 



Figure 4-9. Black crappie, Pomoxis nigro-macidatiis , 8 inches long. 



spines, which number 7 or 8, as compared with 6 in the white crappie. 

 It can also be distinguished by the length of the dorsal fin, which is 

 about equal to the distance between the dorsal and the eye. The dorsal 

 fin contains 15 soft rays. The anal spines number 6. The length seldom 

 exceeds 12 inches. The black crappie often weighs up to 2 pounds, and 

 weights of 4 pounds have been reported. 



The black crappie is common in lakes and large streams over most 

 of the eastern United States and southern Canada. It has been intro- 

 duced on the Pacific Coast. It is abundant in many lakes of Minnesota, 

 Wisconsin, and neighboring states, and is absent only from the deep, 

 rocky lakes of northeastern Minnesota, particularly those of the Lake 

 Superior drainage. It is present in the Lake Superior drainage in Wis- 

 consin (Greene, 1935) . In Minnesota it prefers large streams and 

 medium-sized lakes, and is rare in many of the largest lakes. It is much 

 more common and widespread than the white crappie. 



Crappies may spawn at 1 or 2 years of age. Large ones of 1 1/2 

 pounds may have as many as 140,000 eggs in their ovaries. Smaller 

 females of half-pound weight contain from 20,000 to 60,000 eggs. In most 

 Minnesota waters spawning usually occurs in May and June, though 

 occasionally one may be found spawning in July. The nests are often 

 close together and are sometimes built on bottoms that are softer and 

 muddier than those usually chosen by members of this family. Crappies 

 are easy to propagate in ponds, and they also increase rapidly in lakes. 

 Recent studies on fish populations indicate that they have become 

 overabundant in certain Minnesota lakes, with the result that there are 

 numerous stunted ones. Crowded populations of stunted crappies are 

 caused by the removal of the larger fishes through selective fishing. 

 This same condition frequently occurs with sunfishes in overfished lakes. 



