Forest & Bird is seeking legal intervention to protect the habitats of endangered birds, including the fairy tern, that feed and breed in Northland.
The conservation organisation has filed an appeal in the Environment Court against Northland Regional Council's proposed Regional Plan and called for better protection of mangrove forests that provide habitat for the birds.
"There are only about 36 tara iti [fairy tern] left in the world, so we need to make sure the places where they feed and breed are not disturbed or destroyed," Forest & Bird northern regional manager Nick Beveridge said.
He said critically endangered Australasian bitterns and threatened banded rails also lived in Northland's mangrove forests and these birds could be pushed closer towards extinction if the plan that allowed the removal of up to 200sq m of mangroves got the green light.
The plan marked out areas with significant birdlife, he said, but did not impose any extra rules on mangrove removal or development in those areas.
"Forest & Bird is calling for the plan to protect Significant Bird Areas in the same way that Significant Ecological Areas are protected from harmful development and from the removal of native trees, such as mangroves.
"At present, the plan provides better protection for cockle beds than it does for tara iti - it's just unbelievable.
"The plan is terribly deficient when it comes to protecting the habitat of our most
endangered bird, the tara iti, which is just a heartbeat away from extinction."
Beveridge said Kaipara and Mangawhai harbours were critically important for the tara iti and the bittern, so it would be disastrous if large areas of mangroves were cleared.
Forest & Bird is also calling for stronger rules to ensure water quality is not degraded in lakes, rivers and streams.