Talk How maintain marine fish population in a context of high anthropic pressure: the role of shallow coastal zones – ecological function and fish nursery restoration

According to the most recent assessments of the Census of Marine Life published in August 2010 in the review PlosOne (Coll and al., 2010), the decrease of marine biodiversity is particularly dramatic in the Mediterranean Sea. Causes of biodiversity loss are multiple and mainly due to human activities such as habitat degradation, are recognized as very important. The specificity of fish life cycle increase the risk of populations collapse: A fish female produce several thousand eggs and larvae per year but during this pelagic stage, mortality is very high until 90% due to predation and nutrition. The arrival and settlement of pelagic post-larvae in their permanent benthic habitat is also a critical phase with more than 90% mortality occurring due to predation and habitat degradation. The success of this first part of life cycle (few month) induce the maintain of fish populations.

Our technical platform (CREM) link to the CEFREM lab is dedicated to ecological restoration and we actually have two PHD thesis about the positive role of the harbour on this life cycle. We will present the objectives of both thesis (fish nursery restoration) and initial results.