Work by the Tasman District Council is featuring in a two-day symposium in Wellington looking at ways to improve migration routes for New Zealand's freshwater fish.
More than 90 scientists, engineers and officials are meeting.
Species such as whitebait and eels require free access to and from the sea to complete their life cycles, but can find their way obstructed by tide gates, culverts and dams.
The national fish passage symposium has been organised by the Department of Conservation, Greater Wellington Regional Council, Niwa and the Tasman District Council. Engineers and scientists from more than 50 organisations are attending.
Today and tomorrow attendees will consider the latest research and best practice for restoring and managing fish passage to protect native fish.
Some new and innovative methods for addressing these problems have been developed and will be presented at the workshop as well.
"We want to find the best options and to ensure waterways provide the best habitat for our special native fish," said biodiversity co-ordinator for Greater Wellington Regional Council, Anna Burrows.
Even the removal of small barriers or allowing alternative routes to allow fish to migrate could make a huge difference.
Information presented would be used in a web-based national fish passage guidance resource.
Ms Burrows said TDC resource scientist Trevor James had done "a heap of fish passage work" over a decade or longer and had instigated the symposium.
"He's probably one of the most experienced in fish passage work."
Although the gathering was focusing on native fish, many of which were nocturnal and rarely seen, anything put in to help them would probably also allow salmon and trout to move up and down rivers, she said.
Councils around New Zealand had already assessed more than 1000 in-stream structures.
- The Nelson Mail
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