Report Upon ff)e Recent Epidemic 



(imong F> r o°^ Troat ( Salve linus 



fontinahs) on Long Island. 



By GARY N. CALKINS. 



IN May, 1899, an epidemic started 

 among the brook trout in the 

 hatcheries of a trout farm at 

 Northport, Long Island, and did not 

 abate until every fish had died. The 

 painstaking care taken by the State 

 Shellfish Commissioner, Mr. Edward 

 Thompson, during the last ten years in 

 developing an excellent hatchery and 

 in raising a fine breed of trout, thus in 

 one season received a serious check. 

 At the request of the State Fish Cul- 

 turist, Mr. A. Nelson Cheney, I under- 

 took an examination of the fish for the 

 purpose of ascertaining the direct cause 

 of the epidemic, and if this were due to 

 a parasite, of finding out something of 

 its life history and affinities. Thanks to 

 the courtesy of Mr. Cheney and Mr. 

 Thompson, I was able to get abundant material. 



With the exception of the fungus Saprolcgnia, which does not menace the life of 

 the fish, the brook trout has apparently been very free from disastrous epidemics. In 

 the literature at my command I find no mention of Salvelinus fontinalis or Salmo 

 fario, as subject to any particular disease, and, to my knowledge, the only statement 

 of a parasite in these forms, was made by Csokor in 1 888, in a short description of 

 Gregarinosis.* About ten years ago an epidemic killed off hundreds of the trout in 

 the New York State hatcheries at Cold Spring Harbor, Long Island, but the cause of 

 the trouble was not located and no report was made. From various sources, however, 



* (Gregarinosis d. Forellen, Oesterreich. Zeit. f. wiss Veterinark. Wien 1888, 11, p. 56-58.) 



175 



HOLDING HARD. 



