The diet of native and invasive fish species along the eastern Mediterranean coast (Osteichthyes)

Abstract

The opening of the Suez Canal in 1869 enabled the invasion of more than 100 alien fish species into the Mediterranean. The aim of the present study was to compare the diet of native and alien fish species and to identify possibly shared food resources. We examined the diet composition of 13 of the most abundant fish species (6 alien, 7 native) on shallow soft bottom off southern Israel. All 13 species are omnivorous/carnivorous. The native fish exhibited a wider diversity of food types than the aliens. Alien fish prey upon and are preyed by native species as well as by other alien fish. A high level of diet overlap was found among some species, the aliens Saurida lessepsianus and Scomberomorus commerson overlapped with the native Synodus saurus; and the alien Nemipterus randalli with the native species Pagrus caeruleostictus, Lithognathus mormyrus and Pagellus erythrinus. The identified diet overlap is discussed, and the possibility of competitive interactions between these species is considered.

Keywords:

• Alien species
• Mediterranean Sea
• fish diet

Acknowledgements

We thank the students and members of the M. Goren Ichthylogical Laboratory at Tel Aviv University, for their help sampling, sorting and analyses. We are deeply grateful to Captain of the trawler ‘Motti’ Levy Ornoy and his crew for their warm hospitality and professional help at sea. We thank Ms N. Paz for editing the manuscript and A. Shlagman for identifying the crustaceans.

Disclosure Statement

No potential conflict of interest is reported by the authors.

Additional information

Funding

This research was supported by the Porter School of Environmental Studies, Tel Aviv University, with funding from the Italian Ministry of the Environment, Land and Sea, R&D Project (2007– 2008).