334 



FISHERY BULLETIN OF THE FISH AND WILDLIFE SERVICE 



England conservation laws have made the oper- 

 ation of out-of-state vessels difficult within the 

 3-mile limit where menhaden schools are most 

 abundant (Bunker 1951). 



It is impossible to state to what extent the 

 warming of inshore waters, as indicated by records 

 of surface temperatures at Woods Hole, Boothbay 

 Harbor, and St. Andrews, has affected the re- 

 appearance of menhaden north of Cape Cod. 

 According to Bigelow and Schroeder (1953), 50° F. 

 is the coldest water temperature this fish will 

 tolerate. Menhaden were reported abundant in 

 the Eastport area prior to about 1840-45 (Goode 

 1879, p. 78), but they were not present in that 

 area during the warm period of the 1870's when 

 the menhaden fishery in the Boothbay Harbor 

 region was at its height. In 1876, records of 

 surface water temperatures at Eastport (Goode 

 1879, p. 291) show average July and August tem- 

 peratures of 47.2° and 50.2°, respectively, which 

 are sufficiently low to indicate unfavorable con- 

 ditions for menhaden. In the same year, surface 

 temperatures at Portland, Me., about 30 miles 

 west of Boothbay Harbor, show July and August 

 temperatures of 66.7° and 63.9°, respectively, so 

 that the presence there of menhaden would not 

 be surprising, as far as temperature conditions are 

 concerned. It must be pointed out, on the other 

 hand, that surface water temperature records at 

 Boothbay Harbor over the period 1906-49 show 

 that temperatures in that area have probably been 

 sufficiently high for the presence of menhaden 

 every year (see appendix table 1, p. 344). 



The presence or absence of a migratory species 

 such as menhaden north of Cape Cod during the 

 summer months is not necessarily determined by 

 the inshore conditions where the fish is commonly 

 caught, but may be determined b}" otlier conditions 

 along its migratory route. Unfavorable conditions 

 along the way may act as a barrier (see Role of 

 Temperature in Faunistic Changes, p. 338). 



FLUCTUATIONS IN YELLOWTAIL FLOUNDER 



During the 1940's, a productive ycllowtail 

 flounder (Limanda ferruginea) fishery developed 

 on the southern New England fishing grounds, 

 from Nantucket Shoals westward to Long Island 

 (Royce, Buller, and Premetz, MS.«). In 1942, 

 production of yellowtail amounted to more than 

 60 million pounds, but the catch fell away rapidly 

 to about half that amount by 1944, and by 1949 



to about 10 million pounds. It is natural under 

 such circumstances to ascribe the decline to over- 

 fishing, but Royce and his cowoi-kers found none 

 of the usual symptoms of overfishing in the ex- 

 tensive biological data collected during the rise and 

 fall of this fishery. Paralleling the decline in 

 catches of yellowtail on the southern New England 

 banks was the increase in catches on the south- 

 western part of Georges Bank from about 72,000 

 pounds in 1942 to more than 10 million pounds in 

 1949. 



Royce et al. point out that there have been at 

 least three significant changes in the faunal com- 

 position of the area used by the yellowtail flounder 

 fishery during the 1940's. The Nantucket Shoals 

 area produced many liaddock during the 1920's, 

 the catch amounting to 13,000,000 pounds in 1928. 

 These workers also point out that the haddock 

 were caught in the same location and at exactly 

 the same depth range whicli subsequently pro- 

 duced yellowtail. They explain why yellowtail 

 could not have been abundant during the period 

 of the haddock fishery and also show that haddock 

 were scarce on these same grounds during the 

 period of the yellowtail fishery. Also significant 

 is the fact that during the period of the haddock 

 fishery yellowtail eggs and larvae were abundant 

 to the south and west off the coast of New Jersey 

 in areas where no yellowtail were found in numbers 

 during the 1940's, at which time the demand for 

 yellowtail was at its height. 



With the decline in abundance of yellowtail, the 

 fishermen turned to "trash" species. The produc- 

 tion of this fishery from the southern New England 

 grounds, and largely from the same depths and 

 locations where yellowtail were formerly caught, 

 amounted to about 70,000,000 pounds in 1950 — 

 approximating the peak landings of yellowtail at 

 the height of that fishery. 



Royce, et al.° state that — 



Such changes in the habitat of a few species of fish must 

 be evidence of more fundamental changes in the environ- 

 ment and the entire complex of animal populations. In 

 seeking an explanation we note that the known geographi- 

 cal range of both haddock and yellowtail extends only a 

 little south of the southern New England grounds but 

 much farther to the north * * *. We notice, too, a re- 

 treat of the haddock from the grounds west of Nantucket 

 Shoals northeasterly to Georges Bank in the early 1930's 



» Royce, William F., Raymond J. Buller, and Ernest D. Premetz, 1966. 

 Conservation of the yellowtail flounder Limanda ferruginea. V . S. Depart- 

 ment of the Interior, Fish and Wildlile Service, Washington, D. C. (Un- 

 puhlished MS.) 



