Effects of alien mammals on breeding of ACAP-listed Pink-footed Shearwaters

Pink-footed Shearwater, photograph by Peter Hodum

Pablo García-Díaz (Landcare Research, Lincoln, New Zealand) and colleagues have published in the journal Environmental Conservation on effects of introduced European Rabbits on globally Vulnerable (and ACAP-listed) Pink-footed Shearwaters Ardenna creatopus.

The abstract follows:

“Alien species are a driver of biodiversity loss, with impacts of different aliens on native species varying considerably. Identifying the contributions of alien species to native species declines could help target management efforts.  Globally, seabirds breeding on islands have proven to be highly susceptible to alien species.  The breeding colonies of the  pink-footed shearwater (Ardenna creatopus) are threatened by the negative impacts of alien mammals. We combined breeding monitoring data with a hierarchical model to separate the effects of different alien mammal assemblages on the burrow occupancy and hatching success of the pink-footed shearwater in the Juan Fernández Archipelago, Chile.  We show that alien mammals affected the rates of burrow occupancy, but had little effect on hatching success.  Rabbits produced the highest negative impacts on burrow occupancy, whereas the effects of other alien mammals were more uncertain.  In addition, we found differences in burrow occupancy between islands regardless of their alien mammal assemblages.  Managing rabbits will improve the reproductive performance of this shearwater, but research is needed to clarify the mechanisms by which alien mammals affect the shearwaters and to explain why burrow occupancy varies between islands.”

Reference:

García-Díaz, P., Hodum, P., Colodro, V., Hester, M. & Carle, R.D. 2020.  Alien mammal assemblage effects on burrow occupancy and hatching success of the vulnerable pink-footed shearwater in Chile.  Environmental Conservation  doi.org/10.1017/S0376892920000132.

John Cooper, ACAP Information Officer, 17 May 2020