Burrow architecture of the Sooty Shearwater

Tyler Clark (Institute of Biodiversity, Animal Health, and Comparative Medicine, University of Glasgow, Scotland, UK) and colleagues have published open access in the ornithological journal Ibis on aspects of the burrows of Sooty Shearwaters Ardenna grisea.

The paper’s abstract follows:

“The Sooty Shearwater Ardenna grisea, an abundant but declining petrel, is one of many seabird species that construct breeding burrows, presumably because these confer protection from predators and the elements. Little is known about the causes of variation in Sooty Shearwater burrow architecture, which can differ markedly both within and between breeding sites. We hypothesize that varies in response to habitat type and competition for space. To address these hypotheses, we recorded Sooty Shearwater burrow dimensions on Kidney Island, the largest Sooty Shearwater colony in the Falkland Islands, South Atlantic, and modelled these as functions of burrow density (a proxy for competition) and habitat indices. Our models suggest that Sooty Shearwaters burrow further underground in response to competition for breeding space, and that soil underlying dense tussac grass Poa flabellata is more easily excavated than other substrates, indicating how vegetation restoration could aid the conservation of this species.”

Reference:

Sooty Shearwater, photograph from the West Coast Penguin Trust

Clark, T.J., Bonnet-Lebrun, A.-S., Campioni, L., Catry, P. & Wakefield, E. 2018.  The depth of Sooty Shearwater Ardenna grisea burrows varies with habitat and increases with competition for space.  Ibis doi.org/10.1111/ibi.12631.

John Cooper, ACAP Information Officer, 08 November 2018