Effects of maternal provisioning and temperature on early ontogeny of Cancer pagurus from the North Sea
The influence of temperature and maternal energy provisioning on the offspring was studied in the larvae of the edible crab, Cancer pagurus, from a population off the Island of Helgoland, North Sea. Among freshly hatched larvae from eight females, biomass and elemental composition varied significantly (all p < 0.01), with a pattern of increasing energy supply into larvae produced by larger females. Dry mass (DM) ranged from 12.1 to 17.9 μg-ind, carbon content from 4.6 μg-ind to 5.8 μg-ind. nitrogen from 1.1 to 1.3 μg-ind, and the C:N ratio ranged from 4.1 to 4.4. Larvae originating from the same female but hatched in consecutive nights showed significant variability in biomass and elemental composition. In rearing experiments conducted at five different temperatures (6, 10, 14, 18, 24°C), zoeal development was only completed at 14°C. The results suggest limits of larval growth at elevated seawater temperatures. In the context of global warming, this might be important for futuremanagement of this commercially fished benthic predator. Intraspecific variability in the initial energy content of larvae as well as size-related female energy allocation into offspring is discussed from both an evolutionary and ecological point of view.
Helmholtz Research Programs > MARCOPOLI (2004-2008) > CO2-Coastal diversity - key species and food webs