Predation of Atlantic Petrel chicks by house mice on Gough Island

Abstract

The impacts of predation by invasive mammals on island fauna are a major driver of insular biodiversity loss. Devastating, hitherto unsuspected impacts of predatory house mice on breeding seabirds have been described recently. We studied the fate of 178 Atlantic Petrel Pterodroma incerta nests at Gough Island, over four seasons, from October 2003 to January 2008. Introduced house mice Mus musculus were found in all study burrows checked for mouse visits. From October 2003 to September 2004, we video-recorded attacks by mice on six (of 13) live, healthy Atlantic Petrel chicks and on one (of three) great shearwater Puffinus gravis chicks. In all years, chicks died from mouse attacks. Stage-specific daily nest survival rates were modelled, from which estimates of breeding success were derived that accounted for the variable exposure periods studied among years. Average daily survival rate of eggs was 0.998, and hatching success through the entire incubation period (55.5 days) was 0.924 [95% confidence interval (CI) 0.903-0.940]. Daily chick survival rates were 0.990, which gave a modelled fledging success of 0.247 (CI 0.165-0.338) over the 138-day chick period, and average annual breeding success (chicks fledged per breeding attempt) of 0.228 (CI 0.150-0.318), which is low compared with congeners. Productivity estimates were used as a parameter in a population simulation model, which predicted a population multiplication rate (l) of 0.993 (CI = 0.966-1.021). However, in the one season studied from laying to fledging (2007), from 58 nests, only one chick fledged (1.7%). This suggests the wide errors on the model results may obscure a more severe reality. More than 60% of model simulations resulted in an International Union for Conservation of Nature classification of Endangered. Our results add support to calls to eradicate mice from Gough Island. More generally, mice cannot be ignored as a potential threat to island fauna, and island restoration and management plans should routinely include eradication of introduced mice.

Demographic history of a recent invasion of house mice on the isolated Island of Gough

“…Gough Island is one of the world's most important refuges and breeding grounds for seabirds, such as petrels, albatross, and endemic moorhens and buntings (Wanless et al . , , ). The rapid decline of some of these species has been directly linked to predation by house mice (Cuthbert & Hilton ; Jones et al .…”

Evaluating population impacts of predation by owls on storm petrels in relation to proposed island mouse eradication

“…House mice are one of the most widespread invasive mammals on earth (Bronson 1979, Brooke andHilton 2002) and have been shown to have significant impacts on plant, invertebrate, and seabird communities (Howald et al 2007, Wanless et al 2007, 2012, Angel et al 2009). Mice are present on SEFI year-round but abundance varies dramatically during the year, with low numbers from January to June, a sharp increase in the fall, and then rapid decline in the winter Fig.…”

Genetic distinctiveness of the Waikawa Island mouse population indicates low rate of dispersal from mainland New Zealand

“…Mice on the island hamper the discovery, location and removal of rats when they arrive. In addition, the likelihood that mice are a direct threat to some island bird populations (Russell 2012;Wanless et al 2012) suggests native wildlife would benefit from (Russell et al 2010;Waters et al 2013;Fraser et al 2015). Although the genetic diversity data indicate limited gene flow, it is possible that migrant mice currently reach the island but fail to contribute to the current population.…”