Agenda of Biosecurity and Biodiversity Working Party

Biosecurity and Biodiversity Working Party

14 August 2024

Biosecurity and Biodiversity Working Party Agenda

Meeting to be held in the Council Chamber

36 Water Street, Whangārei

on Wednesday 14 August 2024, commencing at 1pm

Please note: working parties and working groups carry NO formal decision-making delegations from council. The purpose of the working party/group is to carry out preparatory work and discussions prior to taking matters to the full council for formal consideration and decision-making. Working party/group meetings are open to the public to attend (unless there are specific grounds under LGOIMA for the public to be excluded).

MEMBERSHIP OF THE Biosecurity and Biodiversity Working Party

Chairperson, Councillor Jack Craw

Councillor John Blackwell

Councillor Marty Robinson

TTMAC Representative, Michelle Elboz

TTMAC Representative, Mira Norris

TTMAC Representative, Niki Conrad

TTMAC Representative, Nyze Manuel

KARAKIA

RĪMITI (ITEM) Page

1.0 Ngā Mahi Whakapai/Housekeeping

2.0 Ngā Whakapahā/apologies

3.0 Ngā Whakapuakanga/declarations of conflicts of interest

4.0 Reports

4.1 Record of Actions – 20 March 2024 4

4.2 Receipt of Action Sheet 9

4.3 RPMS review 12

4.4 Update on Dune Lakes 14

4.5 Marine Protected Areas 20

4.6 Taharoa Domain 69

4.7 Kauri Protection 72

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Biosecurity and Biodiversity Working Party item: 4.3

14 August 2024

TITLE:	RPMS review
From:	Don McKenzie, Pou Tiaki Pūtaiao - GM Biosecurity; Leon Keefer, Policy Specialist - Freshwater and April Nordstrom, Kaitātari Kaupapa Wai Māori
Authorised by Group Manager/s:	Don McKenzie, Pou Tiaki Pūtaiao - GM Biosecurity, on 05 August 2024

Whakarāpopototanga / Executive summary

The review the Regional Pest Management and Marine Pest Pathways Plan 2017-2027 has begun. This review requires us to undertake a range of prescribed steps that are set out in the Biosecurity Act 1993, but also provides some flexibility in how each step is achieved, provided Council can demonstrate their satisfaction with the overall review process before the Environment Court.

We are proposing to undertake the review over the following 12 months, with the aim of having a new Regional Pest and Marine Pathway Management Plan by August 2025. This review requires us to undertake cost-benefit analyses of all species to be included in our plan,

Recognising the aspirations of our council, Treaty Partners, and our communities, we are proposing a parallel development of a Biosecurity Strategy document that will help drive the delivery and implementation of non-statutory programmes (such as Predator Free 2050).

Ngā mahi tūtohutia / Recommended actions

1. That the Biodiversity and Biosecurity Working Party (BABWP) support the review methodology, consultation plan, and proposed timeline (as presented by the Plan Review Team)

2. BABWP endorses the Plan Review Team commencing targeted consultation and engagement with Treaty Partners, industry representatives, and community pest control groups where appropriate

3. Thats the BABWP support the Plan Review Team testing a draft and any emerging issues with working party members over the coming months and before November.

4. That the BABWP support the development of a first draft RPMP for consideration by Council at its November meeting with the purpose of commencing wider stakeholder consultation.

Background/Tuhinga

The Biosecurity Act 1993 (the Act) (s12B) requires regional councils to provide leadership in activities that prevent, reduce, or eliminate adverse effects from harmful organisms that are present in New Zealand in its region through. NRC does this through a range of programmes, methods, and projects that are led by the teams within the Biosecurity Department.

The framework within which our biosecurity teams operate is provided within the Northland Regional Pest and Marine Pathway Management Plan 2017-2027 (the Plan). This document sets out:

· the responsibilities and obligations of individuals and organisations within the Region to manage unwanted pest species;

· the organisms declared as pests;

· the programmes and attributes of pest species, including objectives and rules

The above includes regulatory measures that prevent the sale and/or propagation of pest species, restrict activities within areas that could increase the risk of pest transmission, and enforcement / prosecution powers where rules have been infringed.

The eradication and management objectives that are set out in the Plan must be realistic and based on the presumption that defined outcomes can be achieved within the life of the Plan.

The Plan Review methodology and timeframe proposed seeks to achieve the legislative requirements that are set out in the Biosecurity Act 1993 while giving effect to NRC’s internal commitments to its communities and Treaty Partners, including our commitments and principles set out in Taiki ē. Consultation with our Treaty Partners and stakeholders will be key to highlight and focus on key areas to implement in the Pest Plan.

Additional aspirations and objectives may be incorporated into a wider Biosecurity Strategy, which is not required under the Biosecurity Act 1993, but may be developed in parallel with the Plan to help coordinate and steer our non-statutory biosecurity programmes.

More information will be provided in a presentation given by the Plan Review team.

Ngā tapirihanga / Attachments

Nil

Biosecurity and Biodiversity Working Party item: 4.4

14 August 2024

TITLE:	Update on Dune Lakes
From:	Lisa Forester, Biodiversity Manager and Jacki Byrd, Biodiversity Specialist - Freshwater
Authorised by Group Manager/s:	Ruben Wylie, Pou Tiaki Taiao, on 06 August 2024

Whakarāpopototanga / Executive summary

Northland dune lakes are fragile, closed ecosystems with around 100 Threatened and At Risk species living in and around them. Many lakes are in decline due to nutrients from land use and pest plants and fish. High nutrient levels and pests threaten rare biodiversity, water for farming, recreational and cultural values. Rare species have already become extinct from a number of dune lakes in Northland.

NRC is continuing to work with iwi/hapū and landowners to reduce the threats and improve the long term health of dune lakes. This includes pest plant control, weed surveillance and partnerships with tangata whenua and landowners to improve lake health. A summary of work undertaken over the last nine months is summarised below as well as an outline of work planned for the 2024/25 financial year.

Ngā mahi tūtohutia / Recommended actions

1. Biodiversity staff to bring a progress report on dune lakes to the first working party meeting in 2025.

Background/Tuhinga

Freshwater Improvement Fund Dune Lakes Project

The Freshwater Improvement Fund (FIF) Dune Lakes Project finished in March 2023. The Ministry for the Environment (MFE) approved an extension to two of the projects work streams to allow more work to be done until June 2024. These two workstreams; pest plant control and partnerships with iwi/hapū have been completed and the final report has been sent to MFE. MFE contributed $33,648 and NRC contributed $ 38,939 to the project extension.

Pest plant control

The project objective was that “invasive plant and fish species threatening biosecurity and biodiversity of selected lakes will be removed or eradicated from at least 14 lakes”. We achieved this objective as invasivee plants (lagarosiphon, hornwort, and egeria) have been controlled in six lakes, pest fish have been reduced in six lakes, and grass carp have been reduced in three lakes. This is a total of 15 lakes.

· Lagarosiphon has not been seen in Lake Ngatu since the control took place in spring 2020. We will continue surveying Lake Ngatu until 2025 to see if we have eradicated the weed.

· Hornwort is at undetectable levels in Lake Egg. We will keep surveying the lake for five years to see if we have eradicated this weed. If more hornwort is found, we will control it again.

· Hornwort is down to 1% of its original extent in Lakes Tutaki, Tutaki Southern Pond, Karaka, Mt Camel North and Mt Camel South outlet. Further surveys and control will be undertaken in the summer of 2024/2025 by NRC.

· Egeria has been significantly reduced in Rotokawau. An estimate 255 kgs of egeria was removed by divers from Rotokawau.

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Description automatically generated Pest plant control summary of achievements.

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Monitoring of water quality variables during pest plant control has shown no evidence of any significant long-term impacts on lake water quality or lake fauna or flora health during the twenty two hornwort control events. Water column visibility was impacted temporarily by the hornwort control. However, there is a wide range of variability in the readings to date but the trend is improving water visibility after an initial deterioration just after control, when the plant was decaying in the lake.

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Drone applying Aquathol K to control hornwort at Lake Tutaki

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Egeria weeding - Rotokawau

Māori partnership’s

The Māori partnership’s objective was: “By 30 June 2024, partnerships will be developed to support six iwi with their own dune lake management.” A summary of the Māori partnerships achievements during the project extension include:

· NRC held hui with Ngati Kuri, Te Aupōuri, Te Rarawa, Ngai Takoto, Te Roroa and Te Uri O Hau iwi during the project extension to find out their priorities and how they would like NRC to support them to achieve their aspirations for improved lake health and rangatiratanga over the roto (lakes) in their rohe.

· Continued grass carp removal from Wai Te Huahua | Lake Heather and Rotootuuru | Swan.

· Site visit to assess gypsy wort at Te Ketekete and work out joint control approach with iwi.

· Attendance in person and at an online hui to discuss options for Lake Wahakari with mana whenua representatives.

· Signage produced and installed for latest hornwort find at Lake Waikanae in the Far North.

· Established Taharoa Domain Operational Working Group, which includes iwi representation.

· Worked with iwi to install Check Clean Dry station at Lake Taharoa over summer to check all watercraft for gold clam.

· Continuous monitoring buoys installed at Lake Taharoa and Ngatu with mana whenua permission.


Tamariki using the Te Ao Māori ika resource at the launch of the booklets.

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Joint project with Te Roroa iwi, Kaipara District Council and NRC running cleaning station at Lake Taharoa over summer to reduce the chance of gold clam reaching the Kai Iwi Lakes.

2. Annual Lakes Ecological Surveys

Annual ecological surveys have been conducted in Northland lakes for more than 20 years with over 100 lakes being monitored every five years on a rotating basis. Ten lakes were visited in May for the annual lake ecological surveys. Lake Report Cards, summarising the findings of the surveys, were received from the contractors and reviewed and sent to iwi and landowners for their information. The final reports cards will be uploaded to the NRC website.

Hornwort was discovered in one Far North lake during the ecological survey. Staff will work with the iwi owners on a control programme. Improved native plant covers were recorded in four of the lakes including Rotokawau (Sweetwater) and Shag (Kai Iwi group).

3. Levels of Service (LOS), budget and work programme for 2024 / 2025

The 2024/2025 Long Term Plan includes the below Levels of Services relevant to lakes:

LOS Measure

Methodology

Number of top-ranked lakes identified in the Northland Lakes Strategy that are under active management.

Active management includes basic care standards for lakes:

-Nutrient management
-Stock proof fencing
-Ecological monitoring
-Submerged weed surveillance
-Weed and pest control if necessary
The lakes are listed and ranked in Northland Lakes Strategy. 12 Outstanding Lakes currently have Management plans. Monitoring records and recommendations for “active management” are recorded as part of the annual lakes ecological monitoring reports.

High value water bodies vulnerable to the effects of climate change are identified and monitored, and work continues to improve their resilience.

The current programme includes approximately 20 high value water bodies, all of which are vulnerable to climate change. These are monitored on a five-yearly (max) cycle for ecological values, and 12 outstanding water bodies are monitored on a monthly basis for water quality. Recommendations from 5-yearly ecological values survey, implemented over time.

The budget for the lakes programme in 2024 / 2025 is:

Lakes Ecological Monitoring	$129,089.
Dune Lakes Kaitiaki Partnership Project	$150,000.

The work programme for 2024 / 2025 includes:

Ngatu, Egg, Tutaki, Tutaki Southern Pond, Karaka, Waikanae, Mt Camel North, Mt Camel South outlet, Carrot	Pest plant surveys, control and surveillance for hornwort and lagarosiphon, in association with Ngāi Takoto, Te Uri O Hau and Te Aupōuri.
Ngatu, Taharoa, Waikare, Kai Iwi	Four high value lakes surveyed annually at high-risk public access points for aquatic weeds.
Rotokawau (Poutō)	Reconnaissance survey to assess the extent of remaining egeria. Removal of pine debris smothering freshwater mussels.
Lake Taharoa	Support biosecurity checks during summer to minimise risk of gold clam reaching Northland lakes. Joint programme with Te Roroa, Te Kuihi, KDC and DOC.
Te Ketekete Lagoon	Support Ngāti Kuri to control and contain gypsywort
Shag, Black, Rotokawau (Poutō), Rototuna.	Lake Restoration plans with Te Roroa, Lakeland Station, Taurua whanau and DOC, and DOC and Te Uri O Hau.
Kai Iwi Lakes	Collaborative work programme with Te Roroa, Te Kuihi, Kaipara District Council and Department of Conservation through regular Taharoa Domain Operational Meetings and reporting to the Taharoa Domain Governance Group.
10 lakes to be determined	Fish and invertebrate survey during annual lakes ecological monitoring weeks 10-14 February and 10-14 March 2025
10 lakes to be determined	Annual lakes ecological monitoring weeks 10-14 February and 10-14 March 2025

4. Cyclone Gabrielle effects on Rotokawau and Rototuna

The Department of Conservation (DOC) commissioned two reports on the effects of Cyclone Gabrielle on Rototuna and Rotokawau on the Poutō Peninsula. The Rototuna investigation compared submerged vegetation in June 2023 to June 2024 and found that the cyclone has significantly impacted lake health and ecosystem resilience. The cyclone caused transformative changes to the lake which is now essentially non-vegetated. This has resulted in a shift towards a turbid, non-vegetated state that may be permanent. Similar devegetation was seen in Lake Taharoa, likely to be the result of Cyclone Gabrielle.

The Rotokawau report compared the counts of kākahi - freshwater mussel’s pre and post relocation and habitat remediation after Cyclone Gabrielle. The pre-cyclone kākahi density in March 2023 was 141 live mussels per square meter. In June 2023 divers remediated the habitat in a treatment area. The mussels were temporarily removed, the area was cleared of pine needles, sediment and organic debris that had smothered the mussels post cyclone. The kākahi were then put back in position. The resurvey in June 2024 found that kākahi in the remediated habitat were in much better condition than the other areas and denser, at 121 kākahi per square meter. In the second treatment area, where pine needles were removed from on top of the kākahi, the densities were significantly lower than original counts, at 40 mussels per square meter. In the control area, where no intervention was done, the kākahi were significantly lower again at 29 mussels per square meter. The report finds the effect of pine debris and extreme weather clearly impact on the health of kākahi.

Conclusion.

There is still much to do to improve water quality and ecological integrity of Te Taitokerau dune lakes and to prevent species extinctions. The NPS-FM requirements and bottom lines need us to establish implementation plans to raise the bar for our lakes. This will take resourcing and input from many people. Building trusting relationships with stakeholders is essential to get action on the ground and improvements in biosecurity and land use change in lake catchments.

Ngā tapirihanga / Attachments

Nil

Biosecurity and Biodiversity Working Party item: 4.5

14 August 2024

TITLE:	Marine Protected Areas
From:	Nicola Hartwell, Kaiwhatahaere Moana Ora and Don McKenzie, Pou Tiaki Pūtaiao - GM Biosecurity
Authorised by Group Manager/s:	Don McKenzie, Pou Tiaki Pūtaiao - GM Biosecurity, on 05 August 2024

Whakarāpopototanga / Executive summary

The Rāhui Tapu / Marine Protected Area rules became fully operative under the Proposed Regional Plan for Northland in October 2023. Since then staff have focussed on: educating the public and local communities on the new rules and the values they intend to protect; establishing working relationships with mana moana hapū and central government stakeholders; obtaining baseline data of the health of the Rāhui; and creating regulatory processes for enforcement. A broad plan for implementation of the marine protected areas has been developed with input from hapū and a report for 2023/24 activities provided with this item.

Ngā mahi tūtohutia / Recommended actions

· That the report on Marine Protected Areas by Nicola Hartwell, Kaiwhakahaere Moana Ora, and Don McKenzie, Pou Tiaki Pūtaiao be received.

· That the Biosecurity and Biodiversity Working Party endorse staff to proceed with developing the project plan in partnership with mana moana hapū.

Background/Tuhinga

In May 2023 the Environment Court released its final decision on new marine protection rules for Mimiwhangata and Rakaumangamanga (Cape Brett), directing Northland Regional Council to implement the new rules via our Regional Plan, as fishing was shown to have been causing significant disruption and deterioration to the ecosystems in these areas. The marine protection rules were approved by the Minister of Conservation in October 2023, becoming fully operative.

Staff have been undertaking implementation activities in partnership with mana moana hapū via mandated representatives. At present, implementation activities are set via hapū mandated representatives and funded under contract. Staff consider this arrangement is sufficient to deliver implementation activities until such time as more formal governance arrangements are established.

Implementation of the marine protection rules has been focussed under three main workstreams: Communication and Public Engagement; Ecological Monitoring; and Compliance Monitoring. Building hapū capacity and capability and achieving consistency with Council’s Te Tiriti o Waitangi strategy, Tāiki ē, underpins each workstream.

Project Plan

A project plan for implementation of the marine protection rules has been drafted and is attached to this item. The plan incorporates feedback from Rākaumangamanga Rāhui Tapu representatives. Staff are awaiting feedback from Mimiwhangata Rāhui Tapu representatives before the plan is finalised for approval. Staff seek an endorsement from the Biosecurity and Biodiversity Working Party to continue to refine and finalise the plan with input from mana moana hapū.

Project Report 2023/24

A project report covering implementation activities for FY2023/24 as identified in the draft project plan is attached to this item. A brief summary of the activities undertaken follows:

Communication and public engagement

· Media release issued on 14 September 2023;

· Signage placed at boat ramps proximate to the Rāhui Tapu;

· Approximately 4,000 pamphlets circulated: during on-water surveillance; via key stakeholders (DOC, NZ Fisheries, marinas, snorkel and dive organisations); and by kaitiaki at boat ramps;

· Council’s website contains information about the rules, the boundary coordinates, the Environment Court judgment and evidence;

· The boundary coordinates are available on MarineMate, Navionics, and NZ Fishing applications, and have been notified by LINZ for inclusion on the charts;

· Social media promotion occurred pre-summer 2023/24, prior to Easter 2024 and the April school holidays;

· Radio advertising occurred as part of Council’s wider Good to Go boating campaign, with additional advertising leading into Kings Birthday Weekend;

· Articles were placed in nine editorials;

· Staff attended four public events;

· A web portal has been created for notification of research activities intended to be undertaken in the Rāhui Tapu;

· Council’s Enviroschools programme delivered “healthy marine ecosystems” education to 16 schools proximate to the Rāhui Tapu, reaching over 1,400 students;

· Council funded Mountains to Sea / Experiencing Marine Reserves to deliver community education (snorkelling days, night snorkel, and estuary experiences).

Ecological Monitoring

· Discussions surrounding the preparation of broad ecological monitoring plans has commenced;

· A tāmure/snapper survey was undertaken in Mimiwhangata Rāhui Tapu;

· Preparation for a kōura survey in the Mimiwhangata Rāhui Tapu is complete;

· University of Auckland undertook a long spined sea urchin survey in Rākaumangamanga Rāhui Tapu and surrounding areas.

Compliance Monitoring

· Enforcement processes have been developed;

· Regular on-water surveillance of both Rāhui Tapu has occurred, with over 220 vessels approached, of which 63 were seen actively fishing and 36 diving.

Consistency with Tāiki ē

Staff have been working with mana moana hapū mandated representatives on implementation activities:

· Signage and pamphlet design were developed with input from hapū;

· Kaitiaki were contracted to deliver communications material and collateral over summer at targeted boat ramps;

· Hapū members have been contracted to perform on-water surveillance in Rākaumangamanga Rāhui Tapu;

· Hapū members were invited and present during on-water surveillance trips in Mimiwhangata Rāhui Tapu;

· Hapū have been instrumental in design and engagement of ecological monitoring initiatives;

· Hapū feedback has been incorporated into the Project Plan.

Going forward

The key tasks for 2024/25 are:

· Work with hapū representatives on finalising the project plan and communications plan 2024/25 and delivery of planned activities. The communications plan 2024/25 generally includes the activities delivered in 2023/24, together with the development of a web-portal to allow the public to report alleged breaches, and the design of posters, social media content, a website update, and media release;

· Development of ecological monitoring plans and achievement of baseline monitoring for both Rāhui Tapu;

· Refinement of regulatory processes to ensure they are effective and consistent with NRC’s Te Tiriti strategy, Taiki ē.

Subject to hapū aspirations, funding is also expected to be put towards bespoke deliverables, such as installation of pou, fixed monitoring cameras and ecological monitoring expertise.

RMA/Fisheries Act Reform

The Ministry for Primary Industries (MPI) has proposed a review of the interface between the Resource Management Act 1991 and the Fisheries Act 1996.

MPI released a short summary document outlining the issues with overlap between the two acts and three possible options for discussion. The options include:

· Option 1: Status quo (the ability of regional councils to control the impacts of fishing for biodiversity purposes under the RMA would continue).

· Option 2: removing the ability of councils to control fishing for biodiversity purposes under the RMA.

· Option 3: clarifying the extent to which councils can control fishing for biodiversity purposes under the RMA.

Council have indicated it supports Option 1 – retain the status quo and staff will continue to monitor this significant and proposed legislative change. Councils’ submission on the review can be read as attachment 3 to this agenda item.

Ngā tapirihanga / Attachments

Attachment 1: Rahui Tapu Project Plan ⇩

Attachment 2: Rahui Tapu - Project Report 2023-24 ⇩

Attachment 3: NRC submission - RMA/Fisheries Act interface - July 2024 ⇩

Biosecurity and Biodiversity Working Party item: 4.6

14 August 2024

0511

TITLE:	Taharoa Domain
From:	Lisa Forester, Biodiversity Manager; Jacki Byrd, Biodiversity Specialist - Freshwater; Ruben Wylie, Pou Tiaki Taiao; Don McKenzie, Pou Tiaki Pūtaiao - GM Biosecurity; Nicky Fitzgibbon, Biosecurity Manager - Incursions and Reponse and Jason Donaghy, Natural Resources Monitoring Manager
Authorised by Group Manager/s:	Ruben Wylie, Pou Tiaki Taiao, on 06 August 2024

Whakarāpopototanga / Executive summary

This report summarises NRC’s involvement in the Taharoa Domain Operational Hui, the planned response to the risk posed by the freshwater gold clam, and water quality monitoring in Lake Taharoa.

NRC staff are part of the Taharoa Domain Operational Hui, a partnership with Te Roroa, Te Kuihi, Kaipara District Council and the Department of Conservation. The hui allow for collaborative and aligned operational work and projects to improve the environmental health of the lakes.

Actions to prevent the invasion of freshwater gold clam are expected to be carried out this summer at Taharoa and elsewhere in Taitokerau. Staff have estimated that $160k will be required to fund preventative activities and this will be sought from the equalisation reserve in accordance with biosecurity incursions that require preventative or immediate response.

Water quality monitoring data collected since 2002 shows for most of the NPS-FM lake water quality attributes Lake Taharoa sits within band A. Total Nitrogen and Total Phosphorus have stayed within the NPS-FM band A-B range. Lake Trophic Level Index has varied between microtrophic and oligotrophic (very low to low nutrient enrichment) which is equivalent to a water quality status of Very good to Good. However, water clarity has dropped, which may be a cause of the loss of submerged vegetation in the lake and requires further investigation.

Ngā mahi tūtohutia / Recommended actions

1. That the working party note the item on Taharoa domain

2. That a further update on Taharoa domain and gold clam is provided at a future working party meeting.

Background/Tuhinga

Taharoa Domain Operational Hui

Northland Regional Council staff from the biodiversity and biosecurity teams are part of the Taharoa Domain Operational Hui that include staff from Te Roroa, Te Kuihi, Kaipara District Council and the Department of Conservation. The purpose of the group is to provide a collaborative, joined-up space for operational programmes, services, activities, and projects relating to environmental monitoring, research programmes and data sharing between partners within the Domain. Staff will meet in August to draft an annual work programme for the Kai Iwi Lakes. The operational hui will provide recommendations to the Taharoa Domain Governance Group as required.

Response to the risk posed by the invasive freshwater gold clam

The primary objective of the biosecurity response to the invasive freshwater gold clam (Corbicula) is to contain its spread within the current known location in the Waikato River and prevent its transmission to other regions. Achieving this objective requires proactive monitoring, enforcement of biosecurity protocols, and targeted interventions to mitigate risks posed by human-mediated pathways.

To reduce the likelihood of the freshwater gold clam being transported to Northland's lakes and waterways, several urgent actions have been undertaken. These include the installation of signage at recreational lakes, social media campaigns, wānanga and information sessions, and the promotion of the Check Clean and Dry (CCD) program.

Efforts have been focused on Lake Taharoa, as it is the region's highest-risk recreational lake with an estimated 75,000 visitors annually. Kaimahi from Te Roroa, Kaipara District Council, Johnson Contracting, and Northland Regional Council conducted biosecurity checks on all visitors with watercraft at Lake Taharoa during the holiday period from December 23rd to February 6th, 2024. The checks involved inspecting all types of watercraft, such as jet skis, boats, and kayaks, as well as their trailers. A water blaster was used for cleaning gear and equipment. Additionally, a temporary washdown station equipped with a water tank, tap facilities, and a water blaster was installed at Lake Taharoa to facilitate the cleaning of gear and equipment brought by visitors.

Human activities are considered the highest risk in facilitating the spread of invasive species like the freshwater gold clam. Having kaimahi present at Lake Taharoa over the summer not only provided useful information to support decision-making but also offered essential engagement and education opportunities with the community.

NRC remains committed to working in partnership to implement practical tools to prevent the spread of freshwater gold clam into Northland. At a minimum, it is recommended to maintain a presence at Lake Taharoa during peak summer months to conduct checks and collect visitor data. Additionally, pre-and post-summer eDNA surveillance should be conducted at Kai Iwi Lakes and other high risk recreational locations in Northland.

Cost estimates for activates over the summer period are in the order of $160K which will include funding for activities such as kaitiaki rangers at Lake Taharoa, updated publicity materials, signage and awareness campaign and Pre and Post eDNA survey and sampling at eight lakes. Funding for these activities could be provided via the equalisation fund which is now available to fund response activities.

Other Legislative Options.

The Regional Pest Management Strategy (RPMS) review is about to commence and staff are in the process of assessing the appropriate rules that could be included to add value and help protect the region from a gold clam incursion.

Water quality monitoring

NRC has been monitoring water quality at Lake Taharoa since 1995. Sampling four times a year, between 2002-2022, was replaced by monthly monitoring in September 2022. Water quality properties that regulate ecological processes and nutrient availability and concentrations, including the NPS-FM attributes, are measured in lake water column. This information is used to assess the state and the long-term trends in water quality and ecosystem health at Lake Taharoa.

Monitoring involves continuously measuring oxygen availability (dissolved oxygen concentration i.e. DO) and water temperature at 15-minute intervals at two different depths – at 0.3 m depth from lake surface and at 0.3 m from lake bottom- by EXO-Sonde equipment attached to a lake buoy, located at the deepest part of the lake. Low lake bottom DO values indicates limited oxygen availability and stress for aquatic life.

Nutrient concentrations in the water column are assessed monthly by measuring total nitrogen (TN) and total phosphorus (TP) concentrations. Other parameters monitored include water level, water clarity, pH, chlorophyll-a, dissolved and organic-inorganic fractions of nitrogen and phosphorus and ammonia (for toxicity). The Lake Trophic Level Index (Lake TLI) is generated using this data to assess lake health and is based on TN, TP, algal level and water clarity.

The depth-integrated and more frequent water quality monitoring at Lake Taharoa is very useful to understand the spatial and temporal variations in lake nutrient concentrations, their drivers and processes in the catchment and their overall impact on dune lake health, e.g. as triggers in algal blooms (measured from chlorophyll-a and phytoplankton concentrations). Such comprehensive knowledge will benefit dune lake management actions.

Water quality assessments

Using the dataset since 2002, overall water quality assessments show for most of the NPS-FM lake water quality attributes Lake Taharoa sits within band A. Nutrients like total N and total P have stayed within the NPS-FM band A-B range throughout the whole monitoring period. Lake TLI at Lake Taharoa varies between microtrophic to oligotrophic (i.e., indicative of very low to low nutrient enrichment) which is equivalent to LAWA lake water quality status of Very good to Good.

A concern is lower water levels at Lake Taharoa which is likely driven by decreasing rainfall and increasing lake evaporation. Declines in lake water clarity (Secchi depth) have been measured (below long-term median of 10m) since the lake level dropped in 2021. This poses serious threat to lake ecological health. Limited light penetration disrupts macrophyte growth. This has become evident as the lake ecological condition went from Excellent (LakeSPI 87%) in 2018 to a Non-vegetated condition (LakeSPI 0%) in 2023. Overall, good water quality in the lake suggests other drivers are the cause of the poor ecological condition.

Ngā tapirihanga / Attachments

Nil

Biosecurity and Biodiversity Working Party item: 4.7

14 August 2024

TITLE:	Kauri Protection
From:	Steven Harwood, Kauri Protection Manager and Don McKenzie, Pou Tiaki Pūtaiao - GM Biosecurity
Authorised by Group Manager/s:	Don McKenzie, Pou Tiaki Pūtaiao - GM Biosecurity, on 05 August 2024

Whakarāpopototanga / Executive summary

In July 2022 Biosecurity New Zealand (BNZ) launched a National Plan for kauri protection and government allocated $32 million for implementation. Since the plan become operative the Northland Regional Council (NRC) has been allocated $1.5M by BNZ to progress kauri protection actions including vector control, fencing, soil sampling, education and construction of boardwalks.

During the past year there have been challenges created by past weather events such as cyclone Gabrielle however a considerable amount of soil sampling and phosphite treatments have been achieved and significant collaborations with mana whenua. In addition, staff have rolled out track upgrades resulting in major improvements to key east coast trails. Control of wild pigs, deer and goats and several large fencing projects were also highlights. The coming year will see less resourcing to undertake track upgrade work however it is expected that soil sampling and survey as well as follow up on management plans and the actions required of them will be a focus. Staff expect to continue with vector control work involving pigs, deer and wild goats and will maintain a moderate level of participation in education and events.

Lastly, there is uncertainty about the level of long- term funding that can be expected by the crown for the National Plan. In addition, and in the short term how activities such as compliance and monitoring are resourced.

A full report on kauri protection activities and expenditure over the last year is attached to this item.

Ngā mahi tūtohutia / Recommended actions

1. That the working party note the information contained in the item and attached report on kauri protection activites.

2. That staff provide a further update to the Biosecurity and Biodiversity Working Party at a future meeting.

Ngā tapirihanga / Attachments

Attachment 1: Report on Kauri Protection 2024- Northland Regional Council ⇩

TITLE:	Record of Actions – 20 March 2024
From:	Sandra Harris, Personal Assistant - Pou Tiakai Taiao
Authorised by Group Manager/s:	Don McKenzie, Pou Tiaki Pūtaiao - GM Biosecurity, on 05 August 2024

TITLE:	Receipt of Action Sheet
From:	Sandra Harris, Personal Assistant - Pou Tiakai Taiao
Authorised by Group Manager/s:	Don McKenzie, Pou Tiaki Pūtaiao - GM Biosecurity, on 06 August 2024