Premium
Physical Condition of Larval Shad during Spring‐Summer in a Southwestern Reservoir
Author(s) -
Kashuba Stephen A.,
Matthews William J.
Publication year - 1984
Publication title -
transactions of the american fisheries society
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.696
H-Index - 86
eISSN - 1548-8659
pISSN - 0002-8487
DOI - 10.1577/1548-8659(1984)113<199:pcolsd>2.0.co;2
Subject(s) - larva , zooplankton , biology , abundance (ecology) , starvation , midgut , zoology , fishery , ecology , endocrinology
Abundance of larval shad Dorosoma spp. declined abruptly in June 1981 and May 1982 in Lake Texoma (Oklahoma‐Texas) after zooplankton density declined in the water column, and starvation of larvae was a possible cause. Specimens from weekly Tucker‐trawl samples taken during spring and summer of 1982 were examined histologically. Comparisons with previously demonstrated histological criteria were used to estimate starvation. Numerical grades were then assigned to tissues based upon the degree of cellular atrophy and deterioration. The tissues examined included cartilage, midgut, liver, pancreas, muscle, and notochord. Shad midgut and organs of digestion showed evidence of poor condition during the period of low zooplankton abundance. These results support the hypothesis that starvation was a factor in the abrupt decline in larval shad abundance in June 1982.