Temperature toleranceof the sea cucumber Holothuria scabra : towards a systematic understanding of multi-level temperature effects

The Sea cucumber Holothuria scabra significantly to the release and recycling of nutrients in tropical coastal ecosystems. Besides its fundamental ecological role, the dried body wall of H. scabra, known as Trepang or Beche-de-mer, is ranked among the highest priced global trade commodities from the ocean. The consequential overexploitation of H. scabra brought the artificial rearing of this species in the center of interest, especially in regions of the Global South. Nowadays, H. scabra has become a key species in community-based aquaculture. Temperature is the key environmental factor that determines biological fitness of H. scabra and thus aquaculture production efficiency. Hence, a detailed understanding of temperature effects on H. scabra are important in two different ways: 1) to determine the optimal thermal range and delimiting critical temperature levels for best aquaculture practices; 2) to predict the susceptibility of H. scabra to future global warming scenarios. This thesis aims to provide first insights into a mechanistic understanding of how temperature affects H. scabra at different biological organization levels.