20 Feb 2014

Conservation on Braided Rivers

From Our Changing World, 9:06 pm on 20 February 2014

Nick Ledger with his spotting scope for looking at birds, and a view of the Ashley River which is a wide shallow braided river

The Ashley River is a typical braided river with wide shallow braiding river channels - it is fed from the foothills rather than the Main Divide, so has fewer floods than some of the larger braided rivers. Nick Ledgard (right) uses a spotting scope to study the rare shorebirds that breed on the Ashley River (images: A. Ballance)

Braided rivers are a distinctive feature of New Zealand, and particularly Canterbury. They form as rainfall from the Southern Alps and its foothills meanders its way across the wide gravel Canterbury Plains. Braided rivers are one of the last native habitats left on the highly modified plains, but they face a range of threats and uses, from gravel extraction and recreational four-wheel driving to introduced predators.

The Ashley-Rakahuri Rivercare group was formed in 1999 to help look after the lower reaches of the Ashley River in North Canterbury. The main aims of the group are to protect birds and their habitat in the riverbed, to monitor breeding success, and to promote these activities to the wider public. The core study area consists of an 18km stretch of riverbed just north of Rangiora, extending from the confluence of the Okuku River down to the State Highway 1 road bridge.

Alison Ballance joins Nick Ledgard to hear about some of the rare shorebirds that breed in the river, and make a quick visit to a wrybill nest.

BRAID – Braided River Aid – is an umbrella grouping of care groups involved in braided river conservation.

Black-fronted tern and black-billed gull colony on the Ashley, and wrybill eggs and nest

A colony of black-fronted terns and black-billed gulls early on in the breeding season, and (right) two wrybill eggs on a 'nest' of small pebbles (images: A. Ballance)