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Range DescriptionPuffinus huttoni breeds in the Seaward Kaikoura Range, north-east South Island, New Zealand. The population comprises two main colonies (Kowhai Valley and Shearwater Stream), sited 10-18 km inland. These were estimated to consist of c.125,000 and c.10,000 pairs (Sherley 1992), but reworking of the original data indicated c.94,000 pairs is more accurate (Taylor 2000). More recently Sommer et al. (2009) reported 106,000 pairs at Kowhai and 8,000 pairs at Shearwater Stream. The total population is estimated to number 300,000-350,000 individuals (Brooke 2004). Numbers and distribution within the Kaikoura Ranges have decreased, with 8 of 10 known colonies having been extirpated this century (Cuthbert 1999). Six out of eight colonies discovered in the high Kaikoura mountains were extirpated by pigs, and feral pigs remain a potential threat the remaining two colonies (Harrow 2009). Since the rapid extirpation of colonies was detected, work has been underway to establish a third population on the Kaikoura peninsula through the translocation of 290 chicks (Anon 2007, Ombler 2010), and predator-proof fencing was introduced in 2010. Individuals have been returning since 2008 (Ombler 2010). For many years this species has been considered to be in a long-term decline (Sherley 1992, Heather and Robertson 1997), but a major study has indicated that the population was stable from at least 1990-2000 (Taylor 2000). Recent evidence even points to a long-term increase in the population for the Kowhai Valley, at an annual rate of 1.7% over the last 20 years, based on burrow density (Sommer et al. 2009). In the non-breeding season birds migrate to waters off southern, western and north-western Australia (Heather and Robertson 1997).