Marine Research Findings of the VECTORS Project

This website provides access to the research results of the VECTORS project, which can be used to support marine management decisions, policies and governance as well as future research and investment. VECTORS was a large scale project that brought together more than 200 expert researchers from 16 different countries. It examined the significant changes taking place in European seas, their causes, and the impacts they will have on society.

Predicting future thermal habitat suitability of competing native and invasive fish species

Climate change is affecting the sea surface temperature, which is expected to result in dramatic consequences for animal life in the near future. Direct effects of temperature changes include fish distribution shift towards higher latitudes and depths and an increase in extinction rates. This appears to be induced by the strong effect that temperature has on fish metabolism which, in turn, affects growth rate, survival and reproduction. In the Mediterranean Sea, warming conditions are considered to be facilitating the incoming and spread of tropical invaders. The increasing success of these species may be partly related to the fact that their optimal temperature, in terms of maximising metabolic scope for activity, is higher than that of indigenous species.


Changes in distribution caused by global warming are likely to have an impact on biodiversity as well as on fisheries and tourism throughout the western Mediterranean Sea.

In this case study, we determined the effect of temperature on the metabolic scope and the consequent thermal habitat suitability (THS) of two herbivorous fish species that occupy a similar ecological niche: the native Sarpa salpa (a species of sea bream), and the invasive Siganus rivulatus, that entered the Mediterranean from the Red Sea through the Suez Canal. They are similar species in terms of habitat use, diet and gregarious behaviour. A modelling approach based on present–day and future scenario for oceanographic conditions was used in order to make predictions on the thermal habitat suitability of the two species both at the basin level (the whole Mediterranean Sea) and in the Sicilian Channel, a key area the determines the inflow of invasive species from the eastern to the western Mediterranean. As a consequences is it possible that, in a near future, the increase in water temperature will cause a shift in the distribution of siganids towards the Western Mediterranean Sea, where they may out-compete Sarpa salpa as has already happened in the Levantine basin. This will have implications for the biodiversity and ecosystems in this area as well as fisheries and potentially tourism as the invasive Siganus rivulatus has venomous spines on the dorsal and pelvic fins which can cause painful injuries.


In the next 50 years the thermal habitat suitability of the invasive siganids will increase throughout the whole Mediterranean Sea and it might expand westwards. However, the western Sicily coasts could act as a temporary barrier for its westward spread.

We found a large difference in the optimal temperature for aerobic scope between S. salpa (i.e. 21.8°C) and S. rivulatus (i.e. 29.1°C), highlighting the importance of water temperature in shaping the energy availability of these two species. The large difference in the optimal temperature for aerobic capacity between S. salpa and S. rivulatus coupled with the increase in water temperature in the eastern side of Mediterranean sea, due to climate change, can provide a mechanistic explanation for the replacement of S. salpa by S. rivulatus species in that region. However, the western Sicily coasts would remain relatively unsuitable for the invasive species, and could act as a temporary barrier for its westward spread. This will have implications for biodiversity, fisheries and potentially tourism.

Relevance for Policy:
  • Alien Invasive Species Directive
  • Common Fisheries Policy
  • Marine Strategy Framework Directive
Further information:

Deliverable 2.1.2: Mechanisms of change in Alien and native species outbreaks

Deliverable 5.1.2: Future distribution and productivity of marine fish and invertebrates

Marras et al., In press. Predicting future thermal habitat suitability of competing native and invasive fish species: from metabolic scope to oceanographic modelling. Conservation Physiology. 


Data availability:

Availability: The data will be published in open access journal: Conservation Physiology


Lead Author:

Paolo Domenici
Institute for Coastal Marine Environment of the National Research Council (IAMC-CNR)
Date of research: September 2014

Related articles:

Response of plaice and sole to climate change 

Changes on stocks and management in saithe fishery 

Climate change: flatfish and shrimp fisheries 

Cod, recruitment, temperature and zooplankton

Connectivity: plaice spawning and nursery areas 

Modelling future scenarios of biogeochemistry 

|< <  1 2 3 4 5 6 7 8 9 10 ...  > >|

Print this page

The content of this website may be subject to copyright, if you wish to use any of the information or figures please contact the attributed author(s).
This project has received funding from the European Union’s Seventh Framework Programme for research, technological development and demonstration under grant agreement no 266445
© Vectors 2015. Coordinated by Plymouth Marine Laboratory.