IMPLICATION OF CLIMATE CHANGE ON THE SUSCEPTIBILITY OF THE BROWN CRAB (CANCER PAGURUS).

The brown crab (Cancer pagurus) colonizes preferentially hard bottomed habitats in the North Sea, at the Atlantic Coast and in the Mediterranean. In face of changing environmental conditions, particularly, the raising water temperature (2°C above normal) the fate of this crustacean remains unclear. The effect of this abiotic parameter on the natural biofilm as well as the susceptibility of crabs to pathogenic diseases is a relevant factor. The American lobster, H. americanus suffers from a significant increase of a bacterial disease of the outer shell, the “Shell Disease”. Comparable symptoms had been observed for several crustacean species in the European area, including the brown crab. In this context the bacterial load of brown crabs will be analyzed under different temperature regimes. Additionally, levels of gene expression correlated with host bacteria interactions in the biofilm of the brown crab will be determined. Experiments will be conducted under natural and controlled conditions to assess the effects of climate change on different brown crab populations. Experimental animals will originate from different European brown crab populations to further determine intraspecific variations in gene expression in response to bacterial loads. The project will provide tools to investigate the effects of climate change on stress symptoms and finally survival of marine species.