Trophic position of dolphins tracks recent changes in the pelagic ecosystem of the Macaronesian region (NE Atlantic)

Dolphins play a key role in marine food webs as predators of mid-trophic-level consumers. Because their mobility and relatively long life span, they can be used indicators large-scale changes the ecosystem. In this study, we calculated trophic position (TP) 5 dolphin species from Canary, Madeira Azores Islands using bulk compound-specific stable isotope ratios muscle tissue to assess adaptations recent availability feeding resources. Dolphin TP values were then compared with those 7 other cetaceans region. Analysis nitrogen isotopes amino acids common indicated non-significant effects basal resources web thus supported use samples for estimations. occupied an intermediate (mean: 3.91 4.20) between fin (3.25) sperm whales (4.95). Species-specific equivalent among islands. However, increased decreased bottlenose (the latter also becoming more oceanic) 2000 2018 Canary Islands. These results suggest different impacts oceanography pelagic Macaronesian region on ecology species.