. Bulletin of the Museum of Comparative Zoology at Harvard College. Zoology. Systematics and Biology of Peprilvs • Horn 227 ". FREQUENCY. Figure 36. Winter (January and February) distribution of the butterfish, Peprilus triacanthus, off the northeastern coast of the United States, 1964-66. Explanation of symbols and other information in Figure 34. fish of 100 mm FL (fork length in P. tria- canthus approximately 10 per cent greater than SL) or less. This indicates that juve- niles spawned earlier in the year are now entering the surf waters along with larger juveniles. Still larger fish we
. Bulletin of the Museum of Comparative Zoology at Harvard College. Zoology. Systematics and Biology of Peprilvs • Horn 227 ". FREQUENCY. Figure 36. Winter (January and February) distribution of the butterfish, Peprilus triacanthus, off the northeastern coast of the United States, 1964-66. Explanation of symbols and other information in Figure 34. fish of 100 mm FL (fork length in P. tria- canthus approximately 10 per cent greater than SL) or less. This indicates that juve- niles spawned earlier in the year are now entering the surf waters along with larger juveniles. Still larger fish were captured in August, September, or October. These large individuals probably move long dis- tances during the summer and autumn even into waters as far north as Newfound- land and the Gulf of St. Lawrence. The seasonal distributions and length- frequency diagrams (Figs. 34-36) do not include surf zone catches but only captures from trawlable waters. The length-fre- quency data seem to correlate well with Schaefer's (1967) data from the surf zone. In summer (Fig. 34), the diagram is essentially unimodal at around 140 mm FL, but it also indicates the presence of juveniles of 50 mm or less. All the fish were collected with a standard 36' trawl having a one-half inch mesh codend liner; the use of a finer mesh probably would have resulted in the capture of more small fish. The data for autumn (Fig. 35) are weakly bimodal and consist mostly of large individuals of around 160 mm FL. This corresponds with the surf zone data which indicated that such large fish were absent from the surf in autumn. This further suggests that different size groups move independently, at least during the summer and autumn. The length-frequency dia- gram for winter (Fig. 36) is strongly bimodal with one peak around 100 mm,. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not
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