Introduction

An explanation of how the health of a marine reserve will be assessed for the report cards and an introduction to the concept of ecosystem health.

Marine reserve report cards are designed to provide a summary of the health of a marine reserve. The cards enable a reader (via print or online media) to quickly understand the status of a marine reserve, important species they may find there and the pressures upon it. Links and references to published reports and research studies are also provided for people who want more detailed information.

Ecosystem health

The health of an ecosystem can be assessed by a concept called ecological integrity. Ecological integrity investigates how native, pristine, diverse and resilient an ecosystem is and if all of its components are present and functioning. It is one measure of how well a marine reserve is working.

Marine scientists at DOC have developed standardised methods of monitoring the ecological integrity of New Zealand’s diverse coastal ecosystems. Monitoring methods are designed to identify the species and habitats that are present and highlight any factors that may degrade the status of a location. The results combine to provide a description of the current state of an ecosystem against which future changes can be tracked.

Marine reserves are the first coastal ecosystems in New Zealand to be assessed for their ecological integrity. The report cards take this assessment of ecological integrity and present it in a public-facing form, summarising the various monitoring and research studies into an easy read pamphlet, with more information provided online.  

New Zealand’s coastal regions 

The marine environment around New Zealand has been classified into 14 distinct coastal biogeographic regions. This classification summarises the expected influences such as climate, currents and tides, and the species that are expected to be found in each region. A map showing the extent of each biogeographic region is available on the Ministry for the Environment website.

A description of each biogeographic region is contained in the Marine Protected Areas: Classification, protection standard and implementation guidelines. See page 32. 

Choosing indicators (or measures)

The ecological integrity of a site can be measured by looking at the status and trend of particular indicators. An indicator is a simple measure that summarises a large amount of complex information about an ecosystem. Indicators can be very useful for tracking trends in response to stress or management actions.

A good indicator:

  • is easy to measure and record in a cost-efficient way
  • responds predictably to stress
  • is clearly understood by non-experts.

Commonly used indicators include water quality, the diversity of species present and the number of introduced species found. The presence of sensitive species (in a healthy condition) is also an indicator of ecological integrity.

Each indicator is represented by a question, such as, how good is the water quality and how is it changing?

How we created the report cards

A process for creating a marine reserve report card was piloted for Cape Rodney–Okakari Point Marine Reserve, in Leigh. 

DOC marine scientists invited iwi representatives, fishing representatives, local scientists and tourism operators to a workshop where they presented their work on ecological integrity and gathered views and priorities for the report card pilot. Those who attended represented Auckland University, Goat Island Marine Discovery Centre, Auckland Council, Ngāti Manuhiri, eCoast, Salt Water Eco, Glass Bottom Boat Ltd. and the Leigh Commercial Fishermen’s Association.

After considering feedback from the workshop, indicators were chosen by DOC that could be used to assess the ecological integrity of Cape Rodney–Okakari Point and eventually other marine reserves. The indicators, which are listed and explained below, are designed to present a broad view of the health of the marine reserve. The stakeholders were also asked for feedback on drafts of the pilot report card document. Feedback was incorporated into the final version where possible.  

Indicators

Scoring system

A scoring system describes the status (the condition of an indicator) and trend (change in status through time) of each indicator. Status and trend are stated for the previous five years, during which time any change would be captured, if regular monitoring was in place. Status is listed as superior, good, fair, poor or undetermined. Trend is listed as declining, stable, improving or undetermined. 

An undetermined status or trend grading may be given for the following reasons:

  • not enough data has been recorded 
  • the data is too variable 
  • the marine reserve was created too recently for adequate data to have been collected
  • natural levels of an indicator against which to compare current levels, are uncertain. 

Where possible, the reason for an undetermined status or trend score will be noted in the report card.  

Assigning criteria for each status depends on the type of indicator, the location of the marine reserve and the available data. While it is relatively simple to assign a water quality rating based on council data, deciding on a score for habitat is more complex. Using the best information available, we have sought a consensus view from our experts, but will develop criteria and limits as more monitoring data is collected. 

Habitat

A diverse marine environment containing an appropriate or expected range of habitats is an indication of ecological integrity. The idea of comparing the current state of an ecosystem with a previous natural or pristine state, however, is fraught, as there is often little or no data to confirm what such an ecosystem looked like. 

In most cases in New Zealand, monitoring was only begun after the formation of a marine reserve. Existing research and survey data therefore provides a record of change in the reserve from that time onwards. 

Question: How diverse is the habitat and how is it changing?
Data: Regular habitat monitoring will provide data for this indicator.

Fish and invertebrate species

The presence of species in a marine reserve that are prized by commercial, recreational and customary fishers is one indicator of ecological integrity. Comparing the number and size of these fish and invertebrates inside and outside a marine reserve will, over time, show how well the marine reserve is protecting species that are harvested outside the marine reserve.

Research in New Zealand and overseas marine reserves has reported greater numbers and larger sized fish and invertebrates inside marine reserves than outside (or at the same location after a marine reserve was established). Marine reserves can protect areas that are important for different life stages, such as the settlement of larvae onto the reef and the growth of larvae, young fish and invertebrates. A larger number of fish and invertebrates inside a marine reserve can also increase their numbers beyond the marine reserve boundary – an effect known as ‘spillover’.  

Larger-scale factors such as changing climate patterns, urban development and overfishing in areas surrounding a marine reserve also influence the number and size of fish and invertebrates within it.

Fish and invertebrate species prized by fishers will vary in different marine reserves but could include:

  • rock lobster
  • snapper
  • scallops
  • blue cod.

One or more than one species can be used as an indicator in this category. 

Question: How many [rock lobster] are present in the marine reserve and how are their numbers changing?
Data: Regular monitoring surveys of the selected species provide data for this indicator.

Water quality

Water quality is a good indicator of ecosystem health because it has a very significant impact on the functioning of marine ecosystems. Water quality is affected by contamination from many sources including wastewater outfalls, discharge from vessels, sediment and nutrient run-off from land. 

Eutrophication (water enriched with nutrients, usually from nitrogen and phosphorus run-off) stimulates plant growth and disrupts the balance of the ecosystem. These conditions can cause an algal bloom, which then creates a toxic environment for many other species.

Question: How good is the water quality and how is it changing?
Data: Regular water quality measurements (including salinity, pH, turbidity, suspended sediment, nitrate and enterococci bacteria) collected by local agencies and researchers provide data for this indicator.

Marine pests

Marine pests are species that are not native to New Zealand, and can have a negative effect on the environment. These species are usually accidentally introduced from overseas by human activities, such as shipping. In 2008, 288 non-indigenous species were recorded in New Zealand’s marine environment.

This indicator considers the invasive species that are present in the reserve, with a particular interest in those highlighted by the Ministry for Primary Industries (MPI). Any marine pest established in nearby locations will also be noted.

Question: What is the impact of marine pests on the ecosystem and how is it changing?
DataMarine Biosecurity provides data for this indicator.

Surrounding land

The use of surrounding land impacts the marine environment through pollution and sedimentation via rivers and streams.

Question: How much is human activity on surrounding land affecting the health of the ecosystem and how is it changing?
Data: Land use maps and other data, as available, will be used for this indicator.

Threatened species

The presence of a threatened species in a marine reserve is noted in the report cards.  

New Zealand has a very diverse marine environment, stretching from subtropical to subantarctic regions. It contains many endemic species (that are found nowhere else), ranging from tiny bristle worms to delicate sponges to dolphins and seabirds. The combination of this diversity and uniqueness has led to a relatively high number of New Zealand species being classified as threatened both locally and nationally.

The New Zealand Threat Classification System classifies threatened species into three classes: Nationally Critical, Nationally Endangered and Nationally Vulnerable. The presence of threatened species from all these classes in a marine reserve will be listed where possible, although lack of data prevents us from using the presence of absence of threatened species as an indicator. 

Disease outbreaks 

The occurrence of disease outbreaks (including those caused by parasite or fungal infections) and algal blooms in the marine reserve or the surrounding area, is noted in the report cards.

Disease outbreaks can have substantial effects on marine species and populations. Increasing international shipping traffic will increase the risk of new organisms, including diseases, entering New Zealand. Climate change is also expected to contribute to outbreaks of new diseases in New Zealand waters and an increase in the frequency and possibly the severity of disease outbreaks.

Toxic algal blooms (caused by the rapid growth and accumulation of certain harmful phytoplankton) can occur during periods of warm settled weather, particularly in nutrient-rich water. The algal blooms are toxic to fish, shellfish and other marine organisms and can also be a human health issue. The Ministry for Primary Industries manages a shellfish monitoring programme and regional councils are responsible for monitoring toxic blooms for public health.

Next steps

Report cards for Cape Rodney-Okakari Point, Tāwharanui and Ulva Island-Te Wharawhara Marine Reserves were published in web and brochure format in 2017. A report card for Taputeranga Marine Reserve was published in 2018. Updated versions (with additional indicators) and report cards for other marine reserves are planned for the future. 

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