Wh 



Ite et al : Reproductive seasonality, fecundity, and spawning frequency of Tautoga onitis 



433 



lu 



o 



-Female {n=476) 

 ■Male In =^79) 



Jun 



Month 



Figure 4 



Gonadosomatic index based on somatic weight (total weight-gonad weight) for tautog col- 

 lected in lower Chesapeake Bay during 1994-95. ?i=sample size; error bars indicate sample 

 standard deviation. 



on the last day female tautog were collected in spawning 

 condition (15 June) instead of the first collection date of a 

 spent female (27 June). 



Tautog were collected (Fig. 1) in spawning condition 

 within the Chesapeake Bay (York River, Buckroe Beach), 

 at the mouth of the Chesapeake Bay (Chesapeake Bay 

 Bridge Tunnel, Cape Henry wrecks, Anglo- African wreck), 

 and at offshore locations (Chesapeake Bay Light Tower, 

 one site 45 km offshore) and there was no apparent trend 

 in spawning season by location. 



Ovarian developmental pattern and type of fecundity 



Ovarian stages defined for tautog (Table 1) are typical of 

 multiple spawning species. Tautog hydrate and spawn 



only a small fraction of the yolked oocytes in the ovary 

 for any one spawning event. Macroscopically, hydrated 

 ovaries appear speckled because of the intermittent occur- 

 rence of large, clear hydrated oocytes among the dominant 

 numbers of opaque, yolked oocytes. Further, the lumen of 

 running ripe ovaries was full of ovulated hydrated oocytes, 

 yet there was still a large volume of tissue with maturing 

 yolked oocytes. The occurrence of spawning stage ovaries 

 over a protracted period also suggested a multiple spawn- 

 ing pattern. Tautog were collected in spawning condition 

 (hydrated and running ripe stages) and the partially spent/ 

 redeveloping stage throughout the April-.June spawning 

 period, but no spent or resting fish were collected until late 

 June, suggesting that individual females were spawning 

 repeatedly during the spawning season. 



