A Decline in the Number of Wedge-tailed Shearwaters Breeding on Raine Island?

Between December 1995 and December 2000 there was an apparent decline of greater than 40 per cent in the number of occupied Wedge-tailed Shearwaters Puffinus pacificus burrows on Raine Island. The estimated census of approximately 3,550 burrows or crevice nests in December 1995 declined to estimates of approximately 2,360 and 1,570 Shearwater burrows or crevice nests in December 1998 and 2000 respectively. Burrow occupancy was approximately 56 per cent in 1998 and 66 per cent in 2000, with eggs or chicks found in 43 per cent of burrows in 1998 and 49 per cent in 2000. Yet the number of occupied ledge crevice nests found in 1998 (130) and 2000 ( 131) was approximately double that found in 1995 (60). The overall decline may be due to turtle nesting activities on the Northern ridge, however further investigation is needed to verify this