Chatham Island Seabird Population Research 2016/17
These are the final reports for POP2016-01 on Chatham Island Seabird Population Research 2016/17. Published February 2017.

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POP2016-01: Objectives 2A, 3A & 4A: Motuhara Searbird Research: December 2016. (PDF, 1,136K)

POP2016-01: Objectives 1A & 1B: Chatham Island Mollymawk Research on Te Tara Koi Koia: November 2016 (PDF, 1,607K)

Summary

Motuhara Seabird Research: December 2016

Motuhara is Maori Land and we are very grateful for the permission of the island owners to camp on the island to undertake this research.

A field team of three (Dave Bell, Dave Boyle and Hamish Tuanui-Chisholm) camped on the island from Dec 5th until Dec 9th 2016.

A full census of Northern Buller's Mollymawks on the island counted 17,682 nests sites. This total is higher than previous counts (2007-09 average 14,699 nests) and is likely to be a result of improved methodology rather than an increase in numbers.

A full census of Northern Royal Albatross on the island counted 1,400 birds incubating eggs. This is significantly lower than that recorded using aerial photography in 2006-2009: average of 2,209 breeding pairs (range 1,879-2,692 pairs). As Northern Royal Albatross are a biennial breeder, without knowing the productivity from last season, it is difficult to determine if this represents a true decline and further research is needed.

A full census of the island counted 1,235 Northern Giant Petrel chicks. Applying a correction factor using breeding success data from the island (which is similar to that recorded from Macquarie Island) the breeding population on Motuhara is estimated to be 1,977 breeding pairs (range 1,769-2,217 breeding pairs). There is no previous full island census to determine population trends.

Chatham Island Mollymawk Research on Te Tara Koi Koia: November 2016

Te Tara Koi Koia, the sole breeding site of the Chatham Island Mollymawk Thalassarche eremita is privately owned by the Daymond Whanau and we are very grateful for their permission to camp on the island to undertake research on Chatham Island Mollymawk.

A field team of two (Dave Bell and Dave Boyle) camped on the island from Nov 9th until Nov 14th.
A full census of the island counted 5296 nests sites of Chatham Island Mollymawk. This result is very similar to previous counts, with the average from 1999-2016 being 5,294 nest sites (range 5,194-5,407, n=11).

Most nests contained breeding birds, with 63.1% of nests containing eggs, 10.8% a chick and 22.6% had already failed; only 3.5% of nests were classified as empty. Chick hatching had only just started during this field trip.

A review of nest occupancy recorded during field trips since 1997 clarifies the breeding timetable of Chatham Island Mollymawk.

A total of 310 band recoveries we made of Chatham Island Mollymawk, this included 3 dead adults, 196 adults incubating eggs, 47 adults guarding a chick, 29 adults on a failed nest, 14 adults on an empty nest, and 21 adults caught away from nests where breeding status could not be determined.
A total of 65 study nests on the Camp Flat and Slopes had birds breeding in them, containing either an egg or chick. A further 9 marked nests were occupied by birds, but were empty.

Publication information

Bell, M.D., Bell, D.J., Boyle, D.P. & Tuanui-Chisholm, H. 2017. Motuhara Seabird research: December 2016. Report prepared by Wildlife Management Ltd for the Conservation Services Programme, Department of Conservation, Wellington. 17 p.

Bell, M.D., Bell, D.J. & Boyle, D.P. 2017. Chatham Island Mollymawk research on Te Tara Koi Koia: November 2016. Report prepared by Wildlife Management International Limited for the Conservation Services Programme, Department of Conservation, Wellington. 24 p.