Hardhead catfish, continued 



fish, various eggs and cysts, hermit crabs, nudibranchs, 

 fish bones, and scales actively taken from living fish 

 (Gunter 1945, Miles 1949, Reid 1955, Darnell 1958, 

 Hellier 1962, Hoese 1966, Harris and Rose 1968, 

 Hildebrand 1958, Dieneretal. 1974, Hoese and Moore 

 1977, Swift et al. 1977, Levine 1980). In addition, 

 hardhead catfish feeding in the surf zone of South 

 Carolina have been found to consume retantians, mole 

 crabs, and isopods (DeLancey 1989). 



Biological Interactions 



Predation : The hardhead catfish is not a major forage 

 species (Fontenot and Rogillio 1970). It has been 

 reported as prey for longnose gar, cobia, bull shark, 

 jewf ish, ladyf ish, spotted seatrout, and red drum (Gunter 

 1945, Miles 1949, Darnell 1961, Branstetter 1981). 



Factors Influencing Populations : Studies have demon- 

 strated that sounds produced by the hardhead catfish 

 could enable it to avoid obstructions, and probably 

 predators, at close range. These sounds may also be 

 used to communicate during breeding and nocturnal 

 schooling (Breder 1968, Tavolga 1962, 1971, 1977). 

 Nematodes have been observed to parasitize hard- 

 head catfish in blister-like swellings under the skin of 

 the caudal region (Gunter 1945). 



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