Braided River

Makarora Braided River – An Underestimated Biodiversity Hotspot

Target threatened species: wrybill / ngutuparore, black-fronted tern / tarapirohe , banded dotterel / pohowera, black-billed gull / tarapuka

Makarora braided river below the Wilkin confluence and the delta adjoining Lake Wanaka

The headwaters of the Makarora River are located within the Otago Region’s Mount Aspiring National Park on the eastern flanks of the Main Divide (Southern Alps) near Haast Pass, the saddle between the Makarora and Haast River valleys. The river flows south into the northern end of Lake Wanaka, 300 m above sea level, after passing the small community of Makarora. Braiding of the river begins at Boiler Flat, approximately 304 m above sea level and flows south west joining the Blue and the Young Rivers, then extending its braid plain further meeting its confluence with the Wilkin River, continuing to the delta before reaching Lake Wanaka. The riverbed is typical of braided rivers in the South Island, containing multiple channels with islands of gravel between them, on which birds nest.

Adult black-fronted tern with juvenile fledgling (Makarora River).

The Aspiring Biodiversity Trust is currently managing a braided river bird survey and monitoring programme which commenced during September 2017.

Survey to date has shown that the Makarora braided river is an important site for indigenous braided river birds such as black-fronted tern, wrybill, black-billed gull and banded dotterel maintaining a diverse and complete braided river avifauna.

Adult female wrybill in alternate plumage. Note characteristic bill, with a curve always to the right.

Cumulative pressures faced by braided river birds such as flooding, native avian predators i.e. Southern black-backed gull (not only introduced mammalian predators such as stoat and rat) and recreational use have also been highlighted.

For further details ABT’s 2017/2018 Makarora braided river bird surveys are available here

This survey and ongoing future monitoring intend to guide and inform future conservation management to help protect, restore and safeguard Makarora’s iconic braided river bird breeding sites.

Endangered black-billed gull nesting colony, Makarora riverbed
Black-billed gull (the worlds rarest gull) nest with two pale-olive eggs

The initial installation of ABT’s invasive mammal predator control strategy commenced on the Makarora River early April 2018. Further details can be found on the news page. The trapping results from April 2018 – end August are found below.

Makarora braided river invasive mammal trapping progress since April – Aug 2018

Invasive mammal trapping result continued from April 2018 – February 2019 summarised within spatial representation below.

Makarora braided river invasive mammal trapping cumulative progress since April 2018 – February 2019

The Aspiring Biodiversity Trust are proud to be working in collaboration with BRaid the national Braided River Aid and Conservation Network. BRaid met with ABT on site to film a promotional video for the Makarora/ Wilkin River (July 2017) to the delta at Lake Wanaka.

Further information

Management and Research Priorities for New Zealand Braided Rivers (2016).