Stomach contents and stable isotope analysis reveal Antarctic prey in short-tailed shearwaters sampled at sea

Short-tailed shearwaters Ardenna tenuirostris are seasonally abundant consumers in the Southern Ocean, but their diet in this region is debated. Among birds found on vessels at high latitudes ( n = 11 live birds and 4 carcasses), at least six had recently ingested Antarctic krill Euphausia superba . Accumulated fresh remains with no flesh attached were also found in the gizzard of two birds. Liver isotopic values suggested that STSHs fed primarily on krill in southerly habitats. Clarifying whether this abundant predator commonly feeds on Antarctic krill is important to better understand and manage the Southern Ocean food webs.