25] STUDY OF SOUTHERN WISCONSIN FISHES— CAHN 25 



FISHES OF SOUTHERN WISCONSIN (WAUKESHA COUNTY) 

 Order RHOMBOGANOIDEA 



Family lepisosteidae 



1. Lepisosteus osseus (Linn.). Long-nosed Gar; Billfish. 



Common in all of the larger lakes in the Oconomowoc and Bark river 

 systems, as well as in Pewaukee and Ashippun lakes. During the greater 

 part of the year the gar is a characteristic species of the topmost stratum 

 of the pelagic environment. A gregarious species, it spends most of its 

 time just under the surface, most commonly over deep water. In the spring 

 and during the breeding season (May and early June) the fish often ascend 

 the rivers to spawn, or deposit the eggs over the weed beds of the shallower 

 waters. The young hatch in from six to eight days, depending upon the 

 temperature of the water, and show a marked tendency to come inshore 

 shortly thereafter. During late June young gar two inches or less in length 

 are often taken from weeds by means of minnow seines drawn along the 

 lake shores. Their growth is very rapid, the young fish attaining a length of 

 five to six inches by the end of the first summer. As they grow, they tend 

 to leave the shore environment and assume their position over the deeper 

 water. The food of the adult is almost exclusively minnows, such as 

 Labidesthes sicculus, Fundulus notatus, Nolropis blennius, but the young 

 of game fish are sometimes found in stomach examinations. Thus I have 

 taken Micro pterus salmoides, M. dolomieu, Leucichthys artedi and Roccus 

 chrysops on numerous occasions. The food of the very young consists almost 

 entirely of entomostraca of a variety of species, but very small minnows 

 appear early in the diet of the fish. About 50% of the food of a gar two 

 and a half inches long is fish life. Minnows are always captured sidewise, 

 after which the gar is likely to descend to a considerable depth while the 

 prey is juggled about and worked into position to be swallowed head first. 

 Economically, the species is of little importance; they are of no food value 

 and do considerable damage by the destruction of the young of food fishes. 



The short-nosed gar, Lepisosteus platostomus Raf., has not been taken 

 by me within the county, but there are records of the species from Rock 

 river near the mouth of the Oconomowoc river, only a short distance from 

 the Waukesha county line. 



Order CYCLOGANOIDEA 

 Family amiidae 



2. Amiatus calvus (Linn.). Dogfish; Bowfin. 



