Fishing and introduced species are among the most important stressors
affecting freshwaters, and can be important selective agents. We examined
the combined effects of commercial fishing and an introduced predator
(Nile perch, Lates niloticus) on life history traits in an African
cyprinid fish (Rastrineobola argentea) native to the Lake Victoria basin
in East Africa. To understand whether these two stressors have driven
shifts in life history traits of R. argentea, we tested for associations
between life history phenotypes and the presence/absence of stressors both
spatially (across 10 Ugandan lakes) and temporally (over 4 decades in Lake
Victoria). Overall, introduced Nile perch and fishing tended to be
associated with a suite of life history responses in R. argentea,
including: decreased body size, maturation at smaller sizes, and increased
reproductive effort (larger eggs; and higher relative fecundity, clutch
volume, and ovary weight). This is one of the first well-documented
examples of fisheries-induced phenotypic change in a tropical, freshwater
stock; the magnitude of which raises some concerns for the long-term
sustainability of this fishery, now the most important (by mass) in Lake
Victoria. Sharpe et al_R argentea
collection and morphological dataPlease see ReadMe
fileSharpe et al_R argentea
egg size and fecundityPlease see ReadMe
file