Table 11. The seasonal distribution of windowpane, Scophthalmua aquosuB , larvae by 



size. Numbers are adjusted to standaitlize sampling effort. Larvae ^ U-l mm rep- 

 resented recent spawning. 



The range of windowpane is somewhat similar to that of 

 fourspot flounder. Although both are most abundant in the 

 northern half of the bight, they are found at different 

 depths. Gutherz (1967) reported windowpane most 

 abundant in depths <46 m; fourspot flounder in depths > 37 m. 

 This is borne out by our larval catches. Windowpane 

 larvae were most abundant off New Jersey over depths be- 

 tween 20 and 40 (Fig. 43); fourspot flounder larvae off New 

 Jersey in 40 m and off southern New England in 70 m (Fig. 28) . 



Both Wheatland (1956) and Perlmutter (1939) caught 

 windowpane eggs and larvae in Long Island Sound as early 

 as April. We caught larvae off Virginia and North Carolina 

 in April, but not as far north as New York until June. Our 

 results indicate a split spawning season off Virginia and 

 North Carolina, but, contrary to Wheatland's findings in 

 Long Island Sound, not in coastal waters off New York. 



Wheatland (1956) doubted that water temperature played 

 a major role in the interruption of spawning in Long Island 

 Sound. Assuming that spawning takes place on the bottom, 

 we see a correlation between water temperatures taken in 

 conjunction with her study (Riley 1956) and the hatching 

 temperatures of 10.0° to 21.1°C reported by Bigelow and 

 Schroeder (1953). During Wheatland's survey of the sound, 

 spawning began in the spring when the average bottom 

 temperature was 7°C and stopped in the summer when it 

 exceeded 20° C. It recommenced in late summer or early 

 fall, soon after the average bottom temperature dropped 

 below 20°C (see Riley 1956). Thus, the upper limits of 

 temperature cited by Bigelow and Schroeder (1953) agree 

 with temperature data collected during the Long Island 

 Sound study. Furthermore, our data suggest that spawning 



is closely tied to temperature. We caught 98% of the 

 recently spawned windowpane larvae, i.e., those <4.1 mm, 

 over bottom temperatures between 6° and 17°C; 70% over 

 temperatures between 8.5° and 13.5°C, a range of 5°. 

 Spawning was interrupted during the summer off Virginia 

 and North Carolina when bottom temperatures exceeded 

 15° C, and began again in the fall when they dropped to 

 14°C. Because bottom temperatures off Long Island during 

 our survey were cooler than those recorded by Riley (1956) 

 during Wheatland's work in the sound, we concluded that 

 spawning was not interrupted by excessively warm water 

 off Long Island during our survey, as it was during 

 Wheatland's (1956) study. 



Syacium papittosum (Linnaeus), dusky flounder.— Dusky 

 flounder are common in shelf waters off our southeast 

 Atlantic coast, and range into the Gulf of Mexico, the 

 Caribbean Sea, and southward to Brazil. Larval stages were 

 described by Futch and Hoff (1971). 



With the exception of one specimen, the distribution of 

 larvae during our survey did not extend north of North 

 Carolina, which conforms with the northernmost range of 

 adults (Gutherz 1967). Throughout the season, we made our 

 biggest catches at stations near the outer edge of the shelf in 

 that area often transected by the meandering Gulf Stream. 



The April collections represented the onset of spawning, 

 which probably had occurred south of Cape Lookout. We 

 caught only four larvae: three of them 36 km off Cape 

 Hatter as over a depth of 55 m, the other at our most 

 seaward station off Cape Lookout where the depth was 145 

 m. Dusky flounder occur at depths from 11 to 384 m, but 



37 



