REDUCED SURVIVAL AND BODY-SIZE IN THE TERRESTRIAL ISOPOD PORCELLIO SCABER FROM A METAL-POLLUTED ENVIRONMENT

Terrestrial isopods (woodlice) may show trade-offs in life history par ameters when exposed to toxins. We have shown previously [Jones and Ho pkin (1996) Functional Ecology 10, 741-750] that woodlice which surviv e to reproduce in sites heavily polluted with metals from an industria l smelting works do not alter their reproductive allocation. This stud y investigates whether there are differences in the survival and body size of Porcellio scaber from these same populations. Specimens were c ollected from eight sites at different distances from the Avonmouth sm elter, UK. The sites represented a gradient of concentrations of Zn, C d, Pb and Cu in the woodlice, from background levels to a grossly cont aminated sites close to the smelter. In laboratory trials, the number of days survived by starved males showed a significant decline with in creased concentrations of Zn in those animals. The maximum size of bot h sexes declined significantly from the least to the most polluted sit es. The most polluted sites had significantly fewer large animals. The cost of detoxifying assimilated metals appears to be reduced energy r eserves and smaller body size. (C) 1998 Elsevier Science Ltd. All righ ts reserved.