Projected climate change and the changing biogeography of coastal Mediterranean fishes

Abstract

Aim To forecast the potential effects of climate change in the Mediterranean Sea on the species richness and mean body size of coastal fish assemblages. Location The Mediterranean Sea. Methods Using an ensemble forecasting approach, we used species distribution modelling to project the potential distribution of 288 coastal fish species by the middle and end of the 21st century based on the IPCC A2 scenario implemented with the Mediterranean climatic model NEMOMED8. Results A mean rise of 1.4 °C was projected for the Mediterranean Sea by the middle of the 21st century and 2.8 °C by the end of the 21st century. Projections for the end of the century suggest that: (1) 54 species are expected to lose their climatically suitable habitat, (2) species richness was predicted to decrease across 70.4% of the continental shelf area, especially in the western Mediterranean Sea and several parts of the Aegean Sea, and (3) mean fish body size would increase over 74.8% of the continental shelf area. Small‐bodied species that are not targeted by either commercial or recreational fleets presented, on average, the highest predicted decrease in geographic range size. Main conclusions Projected climate change in the Mediterranean Sea may have deleterious effects on coastal fish diversity, including a significant loss of climatically suitable habitat for endemic fish species. In addition, climate change may contribute to the loss of small and low trophic‐level fishes, which may have ecosystem‐wide impacts by reducing food supply to larger and higher trophic‐level species. Fishing pressure is already selectively removing large‐bodied species from marine ecosystems, and so fishing and climatic change might act in tandem to drive both direct and secondary extinctions.

Raja asterias population assessment in FAO GFCM GSA17 area

“…The significant increase in the relative abundance observed during the SoleMon surveys could be a response of R. asterias to climate change, fact that has been already demonstrated for other species in the Mediterranean Sea (Cartes et al, 2009;Albouy et al, 2013). Another explanation of such trend could be related to the changes in fishing pressures in certain areas that can cause a recolonization of fishes from less heavily exploited regions (Last et al, 2011).…”

Why the damselfishChromis chromisis a key species in theMediterranean rocky littoral – a quantitative perspective

“…Albouy et al . () attempted to forecast the potential effects of climate change on the species richness and mean body size of coastal fish assemblages in the Mediterranean Sea. Using an ensemble forecasting approach, these authors used species distribution modelling to project the potential distribution of 288 coastal fishes (including C. chromis ) by the middle and end of the 21st century based on the IPCC A2 scenario (http://www.ipcc.ch/ipccreports/sres/emission/index.php?idp=94).…”

“…Small‐bodied species that are not currently targeted by either commercial or recreational fleets presented the highest predicted decreases in geographic range size. For C. chromis (Appendix S3 in Albouy et al., ) future range modifications and centroid shift were determined and these amounted to a slight but insignificant expansion in range (2491 model cells compared with 2516 cells in 2080–2099) in a south‐westerly direction. By contrast, model projections for perturbations to the zooplankton community suggest that strengthening of thermal stratification as a result of climate change, will exacerbate nutrient limitation in the Mediterranean Sea (Durrieu de Madron et al., ), resulting in a decline in zooplankton density in the future and this may well have serious deleterious consequences for the number of planktivorous fish that can be supported in the future.…”

Skills of different hydrographic networks in capturing changes in the Mediterranean Sea at climate scales

“…The atmospheric model follows the observed greenhouse gas and aerosol concentrations up to year 2000 (control period), and the SRES A2 scenario from 2001 to 2100 (scenario period). For a more detailed description of the forcings the reader is referred to Somot et al (2006), Jordà et al (2012) or Albouy et al (2013). Fig.…”