By Gerald Bruce-Smith

Beyond the tramper’s obligatory track-side glances in Arthur’s Pass National Park, there’s a lot of privately funded and managed bird species recovery work going on.

The South Island’s first national park – and the nation’s third – is home to a number of endangered birds, including the Great Spotted kiwi, kea, whio and rock wren. With the threat of predation becoming increasingly recognised in the late 1990s, several key conservation and recovery projects have established in recent years.

By 2003 resident mountaineer Graeme Kates became so concerned with the increasing sightings of stoats and the diminished morning chorus in Arthur’s Pass Village, that he initiated his own local trapping project. The initial catches well surpassed even his expectations.

In early 2005 a partnership was formed between the Arthur’s Pass community, the BNZ Save the Kiwi Trust (BNZSTKT) and DOC. Together, these groups established an extensive trapping network from the Otira Valley carpark to Klondyke Corner. Funded by the BNZSTKT, with on-going voluntary input from the community, this network has since significantly expanded.

Kiwi with radio transmitters are monitored using telemetry and tracker dogs. In 2008, several kiwi chicks were discovered during routine monitoring – an exciting discovery. Increased funding enabled a study of the kiwi population: its territories, health, habits and – most importantly – chick survival. A decision to leave all chick incubations in situ provided an effective gauge of the predator control work. Around 30 birds are currently monitored, including 12 known pairs.

Other birds benefit from the trapping work, and the morning chorus has improved progressively. Several ‘lost’ species have also returned to the valley. Kea numbers within the Bealey Valley have remained encouragingly healthy, with kereru and weka encounters no longer unexpected. In December 2010, this project was incorporated as the Arthur’s Pass Wildlife Trust, a charitable trust.

Another significant turning-point for the future of whio within the national park came in 2005. Some people had concerns that a decline in blue duck numbers in the Deception and Mingha catchments was caused by disturbance during the annual Coast to Coast race. However, race organsier Robin Judkins countered by initiating the Coast to Coast Blue Duck Recovery Programme. The programme established predator control through the valleys to show that stoats and rats provided a much greater threat, and were the real cause of decline.

Such alpine river headwaters are now recognized as the last bastions for whio on the eastern side of the Southern Alps. Given sufficient protection from predators, whio populations from these valleys should spread into the adjacent territories, thereby providing a sustainable population.

Improving predator control has been a driving force for this recovery programme, and under trapper Sam McLeod’s management has expanded into the upper, east and lower Edwards, the lower Bealey, the Otira, and more recently from the Waimakariri Bridge upstream, through into the White and up to Campbell Pass. Whio sighting cards are placed in the key huts, with the DOC biodiversity team at Rangiora monitoring numbers from reported sightings.

This extensive Coast to Coast predator control network also provides protection for other bird species including kea, rock wren, falcon and particularly Great Spotted kiwi, which can be heard from several huts in the area. Private trapping in the Crow Valley commenced in 2008, with whio returning and successfully breeding the next year after an absence of several decades. They provide company for a male kiwi that journeyed over the tops from McGrath Creek several years ago.

To contain the potential movement of mustelids up the true right of the Waimakariri River, and improve predator control at and on Bealey Spur, the local community has also improved their trap placement and monitoring over the past year, with encouraging results. Together, all these trapping regimes, combined with DOC’s extensive work in the Hawdon and Poulter Valleys, give an impressive coverage of the national park and will hopefully halt the decline of native bird species.

Trampers and climbers will no doubt be the best judges of the success of these recovery programmes, and can assist by recording sightings in hut logbooks or reporting them to DOC. For a comprehensive record of the Trust’s work visit the website www.apwt.org.nz and see their display at the Arthur’s Pass Visitor Centre.

Editor’s note: During a five-day trip to the Hawdon and Edwards Valleys this February, I was impressed by the birdlife. We saw numerous kea, heard kiwi every night, and observed two groups of rock wren.

Gerald Bruce-Smith is the secretary and trustee of the Arthur’s Pass Wildlife Trust and a NZAC member. FMC thanks Gerald for sharing his article, which was originally published in the August 2012 FMC Bulletin. It has been republished here on Wilderlife as part of FMC’s 2021/22 focus on Volunteering for Biodiversity. To learn more, visit www.fmc.org.nz/vol4bio.