Rotunno and Cowen: Temporal and spatial spawning patterns of Peprilus triacanthus 
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Figure 4 
Body depth to standard length versus standard length for Peprilus 
triacanthus collected during the spring and summer of 1988 and 
1989. Frame- and Tucker-trawl collections were combined. 
Hatching for P triacanthus in our samples occurs 
from February through at least July and appears to 
be concentrated in two peaks that occur during early 
spring and summer (Fig. 7, A and B). The earliest 
hatching date recorded for fish caught in 1988 was 
19 January 1988 and the latest was 22 July 1988. 
The winter-spring spawning appears to begin in 
January and continue through late April, with an 
apparent peak in March in the SAB (Fig. 7A). A de- 
crease in spawning occurs at this time, although some 
spawning continues at a low level through May (Fig. 
7A). Spring-summer spawning occurs during June 
and July in the MAB with a peak in late June. The 
relative strength of these two spawnings is not clear 
because sampling effort was not equivalent during 
each season. 
Fish caught in 1989 had a similar spawning pat- 
tern to that of fish collected in 1988; the earliest 
hatching date calculated was 14 February 1989, the 
latest was 29 July 1989 (Fig. 7B). Spawning peaks 
occurred in late March to early April in the SAB and 
early to mid-June in the MAB. There appears to be a 
reduction in spawning during the month of May along 
the U.S. Atlantic coast. 
Discussion 
Peprilus triacanthus is the most common species of 
Peprilus found along the Atlantic coast of the United 
States. Within the New York Bight, spawning and 
larval presence for P triacanthus is reported to oc- 
