acclimation temperature of 8°C, AT of 13° C, and 

 exposures varying from 1 to 6 h. Depending on age, 

 mortality ranged between 60 and 100%. The oldest 

 larvae experienced total mortality. Hoss et aL (1974) 

 compared the field-collected larvae of three species 

 of flounder (Paralichthys dentatus, P. lethostigma, 

 and P. albigutta) with the larvae of Atlantic menha- 

 den, Breuortia tyrannus; spot, Leiostomus xanthurus; 

 and pinfish, Lagodon rhomboides, and found the 

 flounders most resistant. The flounders acclimated 

 to 15°C withstood a thermal shock of 18° C for 

 periods of 40 min with a survival rate of 30%. 

 The results of a number of studies (e.g., Schubel et 

 al. 1978) indicate that resistance to thermal shock is 

 age- dependent, with yolk-sac larvae being more 

 tolerant than postyolk-sac larvae. Power plants 

 should be designed and operated to sustain the most 

 sensitive developmental stages of ichthyoplankton. 

 Tests similar to the one described here should be 

 made before site-specific tests are performed and 

 before design and operating criteria are set. Sub- 

 lethal effects, although not considered in this paper, 

 should also be considered in the establishment of the 

 excess temperature that will be utilized in a given 

 season. Such sublethal effects reduce the chances of 

 survival by entrained ichthyoplankton. 



Acknowledgments 



We thank Marion McDonnell for typing the various 

 drafts of the manuscript, Vivian Abolins for drawing 

 the figure, and Peter M. J. Woodhead, William T. 

 Peterson, J. L. McHugh, and Boudewijn H. Brinkhuis 

 for their comments and suggestions. Edward J. Car- 

 penter made available his unpublished winter floun- 

 der data. Grace K. MacPhee, Environmental 

 Reasearch Laboratory, U.S. Environmental Protec- 

 tion Agency, Narragansett, R.I., supplied fertilized 

 winter flounder ova The New York State Energy 

 Administration and Long Island Lighting Company 

 provided financial support. 



Hoss, D. E., W. F. Hettler, Jr., and L. C. Coston. 



1974. Effects of thermal shock on larval estuarine fish — 

 ecological implications with respect to entrainment in 

 power plant cooling systems. In J. H. S. Blaxter (editor), 

 The early life history of fish, p. 357-371. Springer- Ver- 

 lag, N.Y. 



PEARCY, W. G. 



1962. The ecology of an estuarine population of winter floun- 

 der, Pseudopleuronectes americanus (Walbaum). Bull. 

 Bingham Oceanogr. Collect., Yale Univ. 18, 78 p. 

 Rogers, C. A. 



1976. Effects of temperature and salinity on the survival of 

 winter flounder embryos. Fish. BulL, U.S. 74:52-58. 

 Schubel, J. R., C. C. Coutant, and R M. J. Woodhead. 



1978. Thermal effects of entrainment In J. R. Schubel and 

 B. C. Marcy, Jr. (editors), Power plant entrainment: a 

 biological assessment, p. 19-93. Acad. Press, N.Y. 

 Smigielski, A. S. 



1975. Hormonal-induced ovulation of the winter flounder, 

 Pseudopleuronectes americanus. Fish. BulL, U.S. 73:431- 

 438. 



Smigielski, A. S., and C. R. Arnold. 



1972. Separating and incubating winter flounder eggs. Prog. 

 Fish-Cult. 34:113. 

 Smith, W. G., J. D. Sibunka, and A. Wells. 



• 1975. Seasonal distribution of larval flatfishes (Pleuronec- 

 tiformes) on the continental shelf between Cape Cod, 

 Massachusetts, and Cape Lookout, North Carolina, 1965- 

 66. U. S. Dep. Commer.,NOAA Tech. Rep. NMFS SSRF- 

 691,68 p. 

 SOKAL, R. R., AND F. J. ROHLF. 



1969. Biometry: the primciples and practice of statistics in 

 biological research. W. H. Freeman, San Franc, 776 p. 

 Valenti, R. J. 



1974. The effects of temperature and thermal shocks on the 

 development of embryos and larvae of the winter flounder, 

 Pseudopleuronectes americanus. Final report (Contrib. 

 No. SR 73-44) to Long Island Lighting Co., 41 p. 

 (Mimeo.) 



Norman Itzkowitz 

 J. R. Schubel 



Marine Sciences Research Center 

 State University of New York 

 Stony Brook, NY 1 1 794 



Literature Cited 



Barker, S. L., D. W. Townsend, and J. S. Hacunda. 



1981. Mortalities of Atlantic herring, Clupea h. harengus, 

 smooth flounder, Liopsetta putnami, and rainbow smelt, 

 Osmerus mordax, larvae exposed to acute thermal shock. 

 Fish. BulL, U.S. 79:198-200. 

 Bigelow, H. B., and W. C. Schroeder. 



1953. Fishes of the Gulf of Maine. U.S. Fish Wildl. Serv., 

 Fish. BulL 53:1-577. (See pages 276-283.) 

 Committee on Entrainment. 



1978. Introduction. In J. R. Schubel and B. C. Marcy, Jr. 

 (editors), Power plant entrainment: A biological assess- 

 ment, p. 1-18. Acad. Press, N.Y. 



MOVEMENTS OF ROCKFISH 



(SEBASTES) TAGGED IN NORTHERN 



PUGET SOUND, WASHINGTON 



Recreational scuba divers and hook-and-line fisher- 

 men in northern Puget Sound (Fig. 1) have taken an 

 annual catch of 150,000 bottomfish of all species; 

 four species of Pacific rockf ish {Sebastes) account for 

 about 70% of the catch (Washington Department of 

 Fisheries 1977-1980). These four species are copper 

 rockfish, S. caurinus; quillback rockfish, S. maliger; 

 black rockfish, S. melanops; and yellowtail rockfish, 



916 



FISHERY BULLETIN: VOL. 82, NO. 1, 1983. 



