Cottus Life History in Delaware 



75 



SONDJ FMAMJ JASONDJ FMAMJ JA 

 1973 1974 1975 



197B 1979 1980 



MON THS 



Fig. 2. Relationship between gonad weight and body weight in male and female 

 Cottus bairdi from Butler Mill Branch, Sussex County, Delaware, October 1973- 

 March 1975 (solid lines) and September 1978-August 1980 (broken lines). 



dropped markedly in March 1974, at spawning, was low through 

 summer, and increased again in November. The maximum value was 

 reached early in March 1975, and was followed rapidly in mid-March by 

 another sharp post-spawning decrease. The gonosomatic ratio pattern for 

 males was similar to that for females, but monthly differences were not as 

 pronounced (Fig. 2, Table 1). Maximum development in 1974 was in 

 January, followed by a summer decline and a fall increase, and values 



