Our Northland- Tõ Ttou Taitokerau Stories and updates on the great work happening around the region to help our environment, economy and people thrive. Brought to you by Northland Regional Council. Freshwater Improvement Fund helps eradicate aggressive aquatic weed A New Zealand-first operation saw an entire Northland dune lake treated with a herbicide in September of this year. Northland Regional Council staff are optimistic that the operation has been successful in helping to eradicate an unwanted oxygen weed. Lagarosiphon major was causing issues at 56-hectare Lake Ngatu, northwest of Awanui. This invasive plant smothers native plants, affects food and shelter for fish and other wildlife and can make recreational activities like boating and swimming difficult. Biodiversity Advisor Dylan Smith says after thorough research, consultation and monitoring. it was decided that a full-lake treatment (using roughly 7000 itres of the herbicide called Aquathol K, a derivative of Endothall) would be the most effective way of eradicating Lagarosiphon major from Ngatu. Lake Ngatu is home to a number of important native species including the longfin tuna (oe). Photo credit: Irene Middleton, Seacologynz.com lake as they rot. (In this case, the risk was much The operation is part of the council's commitment less likely because there wasn't so much weed it would have caused big changes to the lake's water chemistry once it started dying). Mr Smith says Endothall is a highly selective herbicide that only targets select species, including Lagarosiphon major. The herbicide spares native plants, is non-toxic to fish and aquatic invertebrates and the water can be safely used again within a relatively short timeframe: typically several days. to proactively protect freshwater against aquatic pest plants and future threats, says Deputy Chair Justin Blaikie, who also heads the council's Water The operation was undertaken by airboat through and Land Working Party. a Rotorua-based contractor in September, with "The success at Lake Ngatu builds on our knowledge of the issue, and it means the Department of Conservation and Ngai Takoto we have a solution to the problem of Lagarosiphon major at Lake Ngatu and A dive survey 15 days after the operation showed anywhere else ir's found," he says. involvement from Northland Regional Council, Targeting the lake's oxygen weed problem this Kaitiaki Rangers. way was a national first as the Environmental Protection Agency (EPA) only allows quarter lake the native plant community was thriving but the treatments to avoid the potential for large volumes of dead pest plants lowering oxygen levels in the pest plant had died off significantly. The Ngatu operation was carried out as part of a shared fund with the Ministry for the Environment from their Freshwater Improvement Fund (FIF). LESS LITTER DOWN THE DRAIN How much rubbish goes down the stormwater drain and into the sea - and how do we stop it? That's what we're trying to find out in a joint project with NorthTec, Whitebait Connection and district councils. We're installing "Litta Traps' on 30 stormwater grates around the region and will audit what's captured every three months. The project will help identify litter hot spots to improve education and help tackle rubbish at the source. At the installation of one of the rubbish-catching devices in Onerah From left district councillor Nicholas Connop, Manue Martines from NorthTec, Kim Jones of Whitebait Connection, regional councillor Amy Macdonald, Shelley Burt of Sustainable Coastlines Our Northland- Tõ Ttou Taitokerau Stories and updates on the great work happening around the region to help our environment, economy and people thrive. Brought to you by Northland Regional Council. Freshwater Improvement Fund helps eradicate aggressive aquatic weed A New Zealand-first operation saw an entire Northland dune lake treated with a herbicide in September of this year. Northland Regional Council staff are optimistic that the operation has been successful in helping to eradicate an unwanted oxygen weed. Lagarosiphon major was causing issues at 56-hectare Lake Ngatu, northwest of Awanui. This invasive plant smothers native plants, affects food and shelter for fish and other wildlife and can make recreational activities like boating and swimming difficult. Biodiversity Advisor Dylan Smith says after thorough research, consultation and monitoring. it was decided that a full-lake treatment (using roughly 7000 itres of the herbicide called Aquathol K, a derivative of Endothall) would be the most effective way of eradicating Lagarosiphon major from Ngatu. Lake Ngatu is home to a number of important native species including the longfin tuna (oe). Photo credit: Irene Middleton, Seacologynz.com lake as they rot. (In this case, the risk was much The operation is part of the council's commitment less likely because there wasn't so much weed it would have caused big changes to the lake's water chemistry once it started dying). Mr Smith says Endothall is a highly selective herbicide that only targets select species, including Lagarosiphon major. The herbicide spares native plants, is non-toxic to fish and aquatic invertebrates and the water can be safely used again within a relatively short timeframe: typically several days. to proactively protect freshwater against aquatic pest plants and future threats, says Deputy Chair Justin Blaikie, who also heads the council's Water The operation was undertaken by airboat through and Land Working Party. a Rotorua-based contractor in September, with "The success at Lake Ngatu builds on our knowledge of the issue, and it means the Department of Conservation and Ngai Takoto we have a solution to the problem of Lagarosiphon major at Lake Ngatu and A dive survey 15 days after the operation showed anywhere else ir's found," he says. involvement from Northland Regional Council, Targeting the lake's oxygen weed problem this Kaitiaki Rangers. way was a national first as the Environmental Protection Agency (EPA) only allows quarter lake the native plant community was thriving but the treatments to avoid the potential for large volumes of dead pest plants lowering oxygen levels in the pest plant had died off significantly. The Ngatu operation was carried out as part of a shared fund with the Ministry for the Environment from their Freshwater Improvement Fund (FIF). LESS LITTER DOWN THE DRAIN How much rubbish goes down the stormwater drain and into the sea - and how do we stop it? That's what we're trying to find out in a joint project with NorthTec, Whitebait Connection and district councils. We're installing "Litta Traps' on 30 stormwater grates around the region and will audit what's captured every three months. The project will help identify litter hot spots to improve education and help tackle rubbish at the source. At the installation of one of the rubbish-catching devices in Onerah From left district councillor Nicholas Connop, Manue Martines from NorthTec, Kim Jones of Whitebait Connection, regional councillor Amy Macdonald, Shelley Burt of Sustainable Coastlines