United States Department of the Interior, Oscar L. Chapman, Secretary 

 Fish and Wildlife Service, Albert M. Day, Director 



Fishery Leaflet 391 



Washington 25, D. C, 



March 1951 



TECHNOLOGICAL STUDIES OF THE STARFISH 



RWTTI- STARFISH CONTROL— ITS ECONOMIC NECESSITY AND METHODS USED 



By Charles R Lee** 



INTRODUCTION 



The common five-rayed starfish, Asterias forbesi , is a familiar sight in 

 the pools among the rocks of the New England coast. Not so familiar is the fact 

 that the innocent appearing starfish is one of the most destructive enemies of 

 the oyster and that it may cost the oystermen of Long Island Sound over a million 

 dollars per year for control efforts and in seed and market oysters killed. 



NATURAL HISTORY AND DISTRIBUTION 



In the waters along the shore of Long Island Sound, the lives of the 

 and the oyster are so closely interrelated, that a brief discussion of 

 essential to the understanding of starfish control. 

 Galtsoff and Loosanoff (1939} and Loosanoff and 

 Engle (1940) have. made extensive investigations of 

 both the starfish and oyster and much of the material 

 presented here represents a summary of information 

 from these sources. 



starfish 

 each is 



^i'STl-ARVAL FORM OF STARFISH r~ j 



The starfish will spawn when only one year old 

 if conditions for growth have been favorable. Star- 

 fish spawning usually starts in June, some two to 

 six weeks earlier than oyster spawning in the same 

 waters . Both the starfish and oyster in the larval 

 form are free-swimming for several weeks before 

 setting on the bottom. When first changed from the 

 larval stage, the young starfish is only about one 

 millimeter in diameter, but it has a voracious appetite and grows rapidly. Having 

 spawned earlier, the young starfish may consume the newly-set oyster spat to the 

 extent of virtually wiping out a good set. For this reason, it is desirable that 

 the beds on which old shells are deposited for the purpose of catching the oyster 

 spat be cleaned of as many adult starfish as possible before they begin to spawn. 

 This will not entirely eliminate starfish, as the larvae in the free-swimming 

 stage may be carried in from some distance by the tide and currents. Such cleansing 

 limits the set, however, and is generally the practice in seed-oyster areas. 



The oyster industry of the Long Island Sound area is based on intensive private 

 cultivation. In contrast, on the South Atlantic coast, and to some extent in 

 Chesapeake Bay, oysters are taken from public grounds. In the Sound, almost all 

 of the oysters are grown on privately leased beds and, frequently, they may be 

 moved three or more times during the four to six years it takes them to grow to 

 market size. 



*Chemical Engineer, Fishery Technological Laboratory, Division of Commercial Fisheries, 

 College Park, Maryland. 



note: This leaflet supersedes seps. |93, 196, i99, 204, 206, 208, reprints from commercial 

 Fisheries Review . January 1948, February i948, March 1948, May 1948, June 1948, 

 July i548, respectively. 



