The first global analysis of seabird breeding success in relation to climate has found many species are struggling to produce offspring as ocean temperatures rise.
The study, published in the journal Science, was carried out by an international team of scientists, including the UK Centre for Ecology & Hydrology (UKCEH).
Seabird breeding success depends on the availability of food sources, which is being affected by rising ocean temperatures, and the study found there has been a general downward trend in the number of chicks produced per female per year.
The analysis of 50 years of data from across the world showed declines have been greater in the northern hemisphere, where ocean warming is faster, than in the south. The authors say human impacts like fishing and plastic pollution close to the surface may also be factors. The data show some of the 67 species studied are faring better than others; fish-eating, surface-feeding seabirds are generally worse affected than deeper diving or plankton-eating species.