Trophic niche overlap between round sardinella (Sardinella aurita) and sympatric pelagic fish species in the Western Mediterranean

Ecology and Evolution

Neus Marí‐Mena¹  Antonio Esteban²  José María Bellido²  Maria Grazia Pennino³  Joan Giménez⁴  Marta Albo‐Puigserver⁴  Elena Lloret‐Lloret⁴  Marta Coll⁴  Eneko Bachiller⁴ 

[1] AllGenetics & Biology SL. Oleiros A Coruña Spain;Centro Oceanográfico de Murcia Instituto Español de Oceanografía San Pedro del Pinatar Spain;Centro Oceanográfico de Vigo Instituto Español de Oceanografía Vigo Spain;Marine Renewable Resources Department Institute of Marine Science (ICM‐CSIC) Barcelona Spain;

关键词: diet dissimilarity;    multi‐proxy diet analysis;    prey preference;    small pelagic fish;    trophic interactions;    trophic niche width;   

DOI  :  10.1002/ece3.8293

来源: DOAJ

【 摘 要 】

Abstract The northward expansion of round sardinella (Sardinella aurita) in the Mediterranean Sea, together with declines and fluctuations in biomass and landings of European sardine (Sardina pilchardus) and anchovy (Engraulis encrasicolus) observed in recent decades, may suggest potential inter‐specific competition in the pelagic domain. The coexistence of sympatric zooplanktivorous fish species might therefore be exposed in part to trophic niche overlap and competition for food. Combining visual diet characterization under the microscope with DNA metabarcoding from stomach contents of fish collected in spring results show that predation on relatively large krill is equally important for sardinella than for the other two niche overlapping species. Furthermore, an important overlap is found in their isotopic niche, especially with anchovy, using nitrogen (δ15N) and carbon (δ13C) stable isotopes in muscle tissue. In fact, the three fish species are able to feed effectively in the whole prey size spectrum available during the sampled season, from the smallest diatoms and copepods to the larger prey (i.e., decapods and euphausiids), including fish larvae. Moreover, effective predation upon other large prey like siphonophores, which is observed only when multi‐proxy analyses in stomach contents are applied, might also be relevant in the diet of sardinella. The overlapping diet composition in spring, together with the effective use of food resource by sardinella, can be of special interest in potential future scenarios with warmer water temperature leading to lower zooplankton and/or higher jellyfish availability, where sardinella may take advantage over other species due to its feeding plasticity.

【 授权许可】

Unknown