Data from: Flying south: foraging locations of the Hutton’s shearwater (Puffinus huttoni) revealed by time-depth recorders and GPS tracking

1. The Hutton’s shearwater Puffinus huttoni is an endangered seabird
endemic to Kaikōura, New Zealand, but the spatial and temporal aspects of
its at-sea foraging behaviour are not well known. 2. To identify foraging
areas and estimate trip durations, we deployed Global Positioning Systems
(GPS) devices and Time-Depth Recorders (TDR) on 26 adult Hutton’s
shearwaters during the chick-rearing period in 2017 and 2018. 3. We found
Hutton’s shearwaters travelled much further from their breeding grounds at
Kaikōura than previously considered, with most individuals foraging in
coastal and oceanic areas 125–365 km south and near Banks Peninsula. Trip
durations varied from 1 to 15 days (mean = 5 days), and total track
lengths varied from 264 to 2157 km (mean = 1092.9 km). 4. Although some
diving occurred in near-shore waters near the breeding colony, most
foraging was concentrated in four regions south of Kaikōura. Dive
durations averaged 23.2 seconds (range 8.1 to 71.3 sec) and dive depths
averaged 7.1 m (range 1.5 to 30 m). Foraging locations had higher
chlorophyll a levels and shallower water depths than non-foraging
locations. Birds did not feed at night, but tended to raft in areas with
deeper water than foraging locations. 5. Mapping the spatial and temporal
distribution of Hutton’s shearwaters at-sea will be fundamental to their
conservation, as it can reveal potential areas of overlap with fisheries
and other industrial users of the marine environment.