ASPECTS OF THE LIFE HISTORY OF THE CUTLIPS MINNOW EXOGLOSSUM MAXILLINGUA (PISCES: CYPRINIDAE) (PENNSYLVANIA, NEW YORK)
The cutlips minnow, Exoglossum maxillingua, is a poorly studied cyprinid fish. This dissertation represents the first comprehensive study of its biology.^ Life history studies were conducted using four populations of cutlips minnows. In New York State, the Waccabuc River and Titicus River populations (Hudson River drainage) were studied. Pennsylvania populations from Pine Creek (Susquehanna River drainage system) and the Lehigh River (Delaware River drainage system) were also studied.^ Stomach content analysis showed that cutlips minnow diet changed with age and season. Major food items included hydropsychids, chironomids and taeniopterygids. Studies of various aspects of reproduction showed cutlips minnows spawned between May and July in the Waccabuc and Titicus Rivers. Fecundity was variable and did not correlate with age, length or weight. Outside of their breeding season cutlips minnows did not show obvious external sexual dimorphism. Sex ratios were skewed towards the females. Age, length and weight data showed that New York populations were more robust and longer lived than those of Pennsylvania.^ Experimental studies were conducted on the eye-picking behavior of cutlips minnows. Two conditions were found necessary to initiate eye-picking behavior: (1) Sufficient crowding of cutlips minnows and (2) introduction of a nonconspecific into the same aquarium as the cutlips minnows. Experiments were also conducted to determine if cutlips minnows could be used as models to test hypotheses dealing with the protective value of various eyelines and eyespots. Experiments showed that camouflage in the form of eyespots and eye lines did act to either confuse or misdirect the eye-picking attacks of the cutlips minnow.^ A select group of meristic and morphometric characters were studied over the geographic range of cutlips minnows. Analysis of variance showed significant geographic variation for: head length, eye diameter, body depth, caudal peduncle depth, lateral line scale count, scales above the lateral line, scales around the caudal peduncle, anal fin ray count, pelvic fin ray count, and pectoral fin ray count. The only character not showing significant variation was the dorsal fin ray count. ^
Biology, Zoology|Agriculture, Fisheries and Aquaculture
"ASPECTS OF THE LIFE HISTORY OF THE CUTLIPS MINNOW EXOGLOSSUM MAXILLINGUA (PISCES: CYPRINIDAE) (PENNSYLVANIA, NEW YORK)"
(January 1, 1983).
ETD Collection for Fordham University.