Ohinau Island to the Pacific and beyond - tracking flesh-footed shearwater fledglings

Abstract

**Abstract:** Geolocator tracking of adult flesh-footed shearwaters from breeding colonies in Australia and New Zealand has shown that these adults travel northwards to either the coast of Japan or India (in the case of Western Australia populations) during their non-breeding period. However, there are numerous year-round sightings of flesh-footed shearwaters off the coast of North America; could this be where fledglings go? To gain more understanding of the at-sea movements and distribution of juvenile flesh-footed shearwaters, ten Geotrak Solar satellite tracking devices were deployed on fledglings from Ohinau Island on the Coromandel Peninsula, New Zealand. All ten fledged from the island, but one device never transmitted, and another only transmitted for a few 100 km before stopping. The remaining eight fledglings headed immediately northwards into the Pacific within 10 days of leaving Ohinau Island before slowing down and beginning to forage north of Fiji or east around Samoa and Tokelau. Once in this area, all devices stopped transmitting. Given all of the devices had good battery levels when they last transmitted, it is possible that all these flesh-footed shearwater juveniles were accidentally caught in commercial fisheries in this known high-intensity fishing region. However, despite the very secure attachment method, we cannot rule out that the fledglings did not just simply pull the devices off as the adults are prone to do, although this would be unusual as all the birds would have had to decide to do this at the same time and in the same at-sea region. This work shows the need for continued tracking of all age classes of flesh-footed shearwaters to further determine their distribution and behaviour at sea and importantly, the risk to this species from fishing. **Authors:** Patrick Crowe¹, Dan Burgin¹, Graeme Taylor², Igor Debski², Elizabeth Bell¹ ¹Wildlife Management International Ltd, ²Department of Conservation