Comparative ecology of Pachyptila species breeding sympatrically at Gough Island

Gough Island hosts the world's largest populations of two sympatric prion species, Pachyptila vittata and P. macgillivrayi, with estimates suggesting 1.2–2.0 million breeding pairs. This study reveals significant ecological segregation between the species, including distinct at-sea foraging ranges—P. vittata forages within 1500 km northeast of the colony, while P. macgillivrayi operates within 1000 km south. Temporal segregation is also evident, with P. vittata breeding approximately three months earlier than P. macgillivrayi. Geolocation data, stable isotope analysis, and bill morphology studies further demonstrate trophic segregation, with P. vittata specializing in filter-feeding copepods and P. macgillivrayi exhibiting a more generalist foraging behavior. These findings advance the understanding of ecological strategies in these abundant but poorly studied seabirds.

Jones, C. W. (2018). Comparative ecology of Pachyptila species breeding sympatrically at Gough Island. Unpublished. https://doi.org/10.13140/RG.2.2.29515.41766