The Mediterranean Sea as a ‘cul‐de‐sac’ for endemic fishes facing climate change

Abstract

The Mediterranean Sea is a hotspot of biodiversity, and climate warming is expected to have a significant influence on its endemic fish species. However, no previous studies have predicted whether fish species will experience geographic range extensions or contractions as a consequence of warming. Here, we projected the potential future climatic niches of 75 Mediterranean Sea endemic fish species based on a global warming scenario implemented with the Mediterranean model OPAMED8 and a multimodel inference, which included uncertainty. By 2070-2099, the average surface temperature of the Mediterranean Sea was projected to warm by 3.1 1C. Projections for 2041-2060 are that 25 species would qualify for the International Union for the Conservation of Nature and Natural Resources (IUCN) Red List, and six species would become extinct. By 2070-2099, 45 species were expected to qualify for the IUCN Red List whereas 14 were expected to become extinct. By the middle of the 21st century, the coldest areas of the Mediterranean Sea (Adriatic Sea and Gulf of Lion) would act as a refuge for cold-water species, but by the end of the century, those areas were projected to become a 'cul-de-sac' that would drive those species towards extinction. In addition, the range size of endemic species was projected to undergo extensive fragmentation, which is a potentially aggravating factor. Since a majority of endemic fishes are specialists, regarding substratum and diet, we may expect a reduced ability to track projected climatic niches. As a whole, 25% of the Mediterranean Sea continental shelf was predicted to experience a total modification of endemic species assemblages by the end of the 21st century. This expected turnover rate could be mitigated by marine protected areas or accelerated by fishing pressure or competition from exotic fishes. It remains a challenge to predict how these assemblage modifications might affect ecosystem function.

Multi-element otolith fingerprints unravel sea−lagoon lifetime migrations of gilthead sea bream Sparus aurata

“…However, climate change and water temperature increase in the Mediterranean may disrupt this pattern in the future. Mediterranean Sea temperature is expected to rise by 3.1°C on average over the next century (Ben Rais Lasram et al 2010) and some ecological major changes have already been observed (Sabates et al 2006, Diaz-Almela et al 2007, Ben Rais Lasram & Mouillot 2009). Because warmer winters may allow increasing numbers of S. aurata to overwinter in lagoons, potentially completing their entire life cycle in these habitats, these forecasted environmental changes could have marked impacts on population dynamics, gene flow, and stock structure in the area.…”

First Indo-Pacific fish species from the Black Sea coast of Turkey: Shrimp scad Alepes djedaba (Forsskål, 1775) (Carangidae)

“…In the president study, A. djedaba is reported as second Indo-Paficic species in the Black Sea since the first Indo-Pacififc species Sphyraena obtusata was given by Boltachev (2009). The increase in water temperature has been considered as a main reason for the increasing entry of Indo-Pacific species in the Mediterranean Sea (Ben Rais Lasram et al, 2010;Golani, 2010;Turan et al 2016). Turan et al (2016) reported that there is an increased trend of temperature for the Black Se due to global climate change.…”

Sources, factors, mechanisms and possible solutions to pollutants in marine ecosystems

“…Last but not least, there are the effects of global warming with associated water stratification, depletion of dissolved O 2 and acidification (Matear and Hirst, 2003;Ben Rais Lasram et al, 2010;Keeling et al 2010;Mostofa et al, 2013bMostofa et al, , 2013d. These problems add to overfishing by impacting water quality and/or enhancing the deterioration of food resources for fish, with consequences that span from disease and mortality of fish communities to severe reduction of fish breeding in marine ecosystems.…”