Northlanders urged to look after their wetlands

Hunting for rare Northland mudfish in a small area of gumland wetland behind Bay of Islands Airport.

Northlanders are being urged to rethink the value of wetlands, which serve often under-appreciated but environmentally crucial roles including filtering, absorbing and storing excess waters for dry periods.

World Wetlands Day is celebrated every February 2, marking the adoption in 1971 of the Convention on Wetlands in Ramsar, Iran, but the Northland Regional Council says they are of huge value every day.

NRC chairman Bill Shepherd said healthy wetlands were effectively the environment's kidneys, filtering rain, including floodwater, and storing it, which was especially valuable during dry periods.

"Climate change means extreme weather events like droughts, storms and floods are on the increase, which will make our wetlands even more important to us in the future.

Wetlands also help fight climate change because they store carbon better than any other habitat on the planet," he said.

The elusive quarry - a rare Northland mudfish. Pictures / NRC

NRC biodiversity manager Lisa Forester said more than a fifth of the region had once been covered in wetlands, including vast swamps and gumland heaths extending from the edges of the Kaipara Harbour to Spirits Bay. Less than 5.5 per cent, less than half the national average, of those original wetlands remained.

Shepherd said the regional council did a vast amount of work in the wetlands area, including its Top Wetlands Project, a database that had seen the ranking and prioritisation of around 1000 Northland wetlands. The council had contacted the approximately 600 owners of the more than 150 of the highest-ranked wetlands, and was working with them via biodiversity plans and funding assistance for fencing and protection, including covenants where possible.

Forester said 87 wetland enhancement projects had been completed since 2014-2018, to which the council had contributed $389,000, with a further 24 projects currently under way.

Last year 21 wetlands received funding for fencing and protection, and the council aimed to target 25 annually for assessment of fencing needs and associated follow-up. Wetland condition index monitoring, using national methodology, was in place at 27 locations that had already been fenced under the council's Environment Fund.

"Monitoring began in 201l, and this summer is in its third cycle. Pleasingly, nearly all the degraded wetlands we're monitoring have improved their scores, while those that were already in good condition have remained stable or improved," she said, adding that Northlanders – farmers, iwi and small block owners – cared deeply about their wetlands, and the results were testament to that.

"This is not just through fencing, but with pest and weed control in most cases. Wetland owners often come and help with the monitoring, and get pretty excited when they see the condition scores improving," she said.

Meanwhile, Northland was home to almost all of New Zealand's remaining viable nationally endangered gumlands/wet heathlands. A mapping project capturing remaining wet heathlands had been completed, and would help with the application of new proposed regional plan rules, developed to prevent further loss of the endangered habitats.

Shepherd said the council also carried out a range of biosecurity work on freshwater/wetland weeds and pest fish, including surveillance, delimitation, survey and eradication, actively controlled pest species like koi carp, and responded to reports of others in the wild, including red-eared slider turtles and water dragons.

"And while undertaking threatened species work isn't one of our key programmes, council is involved in work that benefits rare species that live in our wetlands, including bitterns, the nationally critical native bladderwort (support research), Omapere quillwort, dune lakes galaxias research and tuna (eels), etc," he said.

General information about wetlands can be found at www.nrc.govt.nz/wetlands.