Rationale
(Changed due to Application of criteria)
The regional population of Kerguelen Petrel Lugensa brevirostris satisfies the criterion for regionally Vulnerable under D2 (population with a very restricted area of occupancy, or number of locations (typically five or fewer) such that it is prone to the effects of human activities or stochastic events within a very short time period in an uncertain future, and is thus capable of becoming Critically Endangered or even Extinct in a very short time period). However, it was felt that the population of Kerguelen Petrels breeding at South Africa's Prince Edward Islands is unlikely to be impacted by stochastic events or human activities to such an extreme degree within a short time period. As a result, the Kerguelen Petrel was assessed as regionally Near Threatened.
Distribution
The Kerguelen Petrel breeds at several island groups in the Southern Ocean including Gough, Tristan, Amsterdam, Crozet, Kerguelen, Prince Edward and Marion islands (Marchant and Higgins 1990). Outside of the breeding season, birds disperse across the Southern Ocean (Reid 2002). The core of the species' range is south of the Polar Front and it is a rare vagrant to continental waters. It is prone to occasional irruptions in large numbers, along with other seabird species such as the Blue Petrel Halobaena caerulea (Brooke 1981).
Population
The global population is estimated at 1 million individuals (Brooke 2004). Barnes and Huyser (1998) reported that Kerguelen Petrel numbers on Marion and Prince Edward Islands number in the thousands, but do not provide a more accurate estimate. Confidence in this regional population estimate is low.
Population trend
The global population is thought to be stable in absence of any evidence showing declines (BirdLife International 2014). The regional population trend is thought to be positive due to the removal of domestic cats Felis catus from Marion Island in the early 1980s (Cooper et al. 1995). The confidence in this regional trend estimate is medium.
Threats
Predation by alien species has impacted Kerguelen Petrel numbers at several islands including Marion Island (Marchant and Higgins 1990, Cooper et al. 1995). Removal of cats from Marion Island in the early 1980s has negated this threat (Cooper et al. 1995). Mouse predation on burrowing petrel chicks at Gough Island (Wanless et al. 2007, 2012) and the discovery of mouse predation on albatross chicks at Marion Island (Jones and Ryan 2010) suggest mice could be a threat to this species at Marion Island.
Conservation
Underway
No conservation measures focused specifically on the Kerguelen Petrel are currently underway, but various generic conservation principles are in place at its breeding islands. The Prince Edward Islands are listed as a Ramsar Wetland of International Importance, as a Special Nature Reserve under the Environment Conservation Act (No 73 of 1989) and the Prince Edward Islands Management Plan 1996. The Prince Edward Islands Marine Protected Area was proclaimed in 2013. Various stringent guidelines are in place to prevent pollution, contamination, disturbance and introduction of pathogens or invasive organisms on the islands.
Proposed
None, as there are no overt threats to this species in the region. Research on the threats facing the breeding population of Kerguelen Petrel on the Prince Edward Islands is needed. In particular the impact of predation by introduced mice should be investigated and mitigated as a matter of urgency.
Research
* As for all the burrowing petrels at the Prince Edward Islands, very little, if any demographic data are available, even the most basic information required for demographic models. Population estimates at both Prince Edward and Marion islands would be useful for establishing a baseline and thereafter assessing trends.
