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Fishery Bulletin 101(2) 



Figure 1 



Map of lower Chesapeake Bay and nearby coastal waters of Virginia. Closed circles indicate 

 sites where tautog were collected; open circles indicate collection sites of tautog in spawning 

 condition. CBBT = Chesapeake Bay Bridge Tunnel. CELT = Chesapeake Bay Light Tower. 



weighed to the nearest 0.01 g (GW). Maturity classification 

 was assigned as outlined in Table 1, based on eight macro- 

 scopic stages, modified from Lowerre-Barbieri et al. ( 1996) 

 for multiple spawning species. One gonad was randomly 

 chosen by coin toss for histological processing and placed in 

 Davidson's fixative. For females staged macroscopically as 

 spawning females, the remaining ovary was placed in 10% 

 neutrally buffered formalin for batch fecundity counts. 



Whole unsectioned opercle bones are the accepted 

 method to age tautog (Cooper, 1967; Simpson, 1989;Hostet- 

 ter and Munroe, 1993). Opercle bones were removed and 

 processed to examine age at maturity and age-related 

 fecundity. Opercles were boiled for 1-3 minutes to remove 

 flesh, scrubbed under warm flowing water, dried for two 

 days, and read with transmitted light. Age of each fish 

 was determined from two readings of both opercles (when 

 possible). An annulus was defined as the transition from 

 a translucent zone to an opaque zone. Annulus formation 

 was previously validated by Hostetter and Munroe ( 1993). 

 1 April was used as a birth date to allow maximum growth 

 within the biological year (April to March), and to avoid 

 overlap with fish in the next year class. 



Gonads selected for histological processing were placed 

 in Davidson's fixative for two days before transverse sec- 



tions of anterior, middle, and posterior ovarian tissue (or 

 anterior and posterior sections of testes) were taken and 

 placed in tissue cassettes. Variation between left and right 

 gonads was accounted for by random selection of one go- 

 nad for fixation. Tissue samples were then rinsed overnight 

 with flowing tap water and placed in TO'^r EtOH. Standard 

 histological processing (tissue embedded in paraffin, sec- 

 tioned at 5-7 pm, and stained with Harris's hematoxylin 

 and eosin-Y) (Luna, 1968) was performed for all samples. 

 Male gonads were classified microscopically into two 

 stages: sexually mature or immature. Female microscopic 

 gonad stages were assigned based on the occurrence and 

 relative abundance of seven oocyte developmental stages 

 (Wallace and Selman, 1981; West, 1990; Hunter et al., 

 1992): primary growth, cortical alveoli, partially yolked, 

 advanced yolked, germinal vesicle migration, germinal ves- 

 icle breakdown, and hydrated oocytes. Final oocyte matura- 

 tion (FOM) comprises germinal vesicle migration, germinal 

 vesicle breakdown, and hydrated oocyte stages (Wallace 

 and Selman, 1981; West, 1990). Fully developed ovaries 

 were distinguished from partially spent/redeveloping 

 ovaries by the presence of postovulatory follicles (POFs). 

 Microscopic gonad stages are described in "Description of 

 microscopic gonad stages," ("Results" section), summarized 



