Effects of temperature on life history variables in perch

Abstract

Population structure, recruitment, mortality, life expectancy, age at maturity, gonad development, fecundity, net reproductive rate and energy storage were studied in a perch population exposed to thermal discharge. The experiment was conducted during 1978-1990 in an artificial enclosure at a nuclear power plant on the Baltic Sea coast. Abundance increased after the plant started operating, although the proportion of larger perch dropped to a low level. Recruitment improved, but adult mortality increased. This effect was accentuated as the fishes matured very early and at a very small size, reducing their ability to support a growing gonad in high winter temperatures. During the spawning period, condition dropped to very low levels accompanied by increased mortality. Surviving fish delayed the next spawning by one or more years and reduced their fecundity. Body condition thus improved in large perch at the end of the study period. Life-time fecundity was reduced, and reproductive performance shifted to younger ages. 1995 The Fisheries Society of the British Isles

Impact of environmental temperature on Atlantic cod Gadus morhua energy allocation to growth, condition and reproduction

“…Many studies have shown that fish in warmer waters mature at a younger age (Sandstrom et al 1995, Morgan & Colbourne 1999, Grift et al 2003. However, for southern Grand Bank cod, both low and high temperatures resulted in earlier maturation.…”

Experimental manipulations of tissue oxygen supply do not affect warming tolerance of European perch

“…Wild European perch (N=22) were caught by hook and line in the Biotest enclosure (∼1 km 2 ), a man-made enclosure in the Baltic Sea receiving heated water from the cooling system of the nuclear power plant in Forsmark, Sweden (Hillebrand et al, 2010;Sandstrom et al, 1995). Fish were transported by road (<1 km) to a field laboratory and separated randomly between two 1000 l tanks containing air diffusers and flowthrough seawater pumped from the Biotest enclosure (23±1°C; salinity 5 ppt).…”

Longevity and growth strategies of the desert tortoise (Gopherus agassizii) in two American deserts

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