EXECUTIVE SUMMARY

The Department of Conservation (DOC) aims to implement a monitoring programme to enable reporting on the status and trend of freshwater biodiversity at a national scale. This necessitates the development of a monitoring and reporting framework and set of indicators that would holistically assess freshwater biodiversity values, and a network of sites to provide an unbiased representation of the status and trend of freshwater ecosystems nationally.

The purpose of the report is to scope the development of a freshwater biodiversity monitoring programme including; 1) providing the context for biodiversity monitoring within DOC, 2) describe existing monitoring frameworks used within and outside of DOC that may be suitable for developing a national freshwater biodiversity monitoring programme, 3) identify a range of indicators and measures that are appropriate for use in a proposed freshwater framework, and 4) provide a broad summary of existing freshwater monitoring by DOC and other management agencies that could be used to inform the framework.

1. Context for DOC biodiversity monitoring

The Department of Conservation has developed a biodiversity monitoring and reporting system as part of Natural Heritage Management System (NHMS). It consists of a hierarchical integrated monitoring system with broad scale Tier 1 monitoring to inform the status and trends of key indicators on public conservation land (PCL), Tier 2 monitoring associated with select high priority managed areas through DOC's ecosystem and species optimisation projects, and Tier 3 monitoring at a small number of sites designated for development of management practices ( e.g. ecosystem or species restoration). Using a nested hierarchy DOC aims to collect information with different levels of scope and spatial coverage to report on gains and losses in biodiversity across all areas of its responsibility.

2. Existing monitoring frameworks

As part of the initial process around designing a biodiversity monitoring and reporting system, the Department engaged Landcare Research to develop a framework for monitoring and reporting on the status and trend of ecological integrity (Lee et al. 2005). Ecological integrity (EI) was defined as the full potential of indigenous biotic and abiotic factors, and natural processes, functioning in sustainable communities, habitats, and landscapes (Lee et al.2005). Although the focus of the framework was principally in relation to terrestrial ecosystems, it did consider aspects of freshwater ecosystems. Several other freshwater monitoring frameworks were considered in relation to the goals of the Tier 1 monitoring and reporting programme, including the Cross Departmental Research Pool (CDRP) freshwater ecological integrity framework, the Ministry for the Environment (MfE) national environmental monitoring and reporting (NEMaR) framework, the wetland condition index, and the DOC Arawai Kākāriki wetland monitoring framework. The CDRP freshwater framework for assessing EI was the broadest framework and was based on a range of indicators that together quantify the core components of nativeness, pristineness, diversity and resilience, with many being highly relevant to Tier 1 biodiversity monitoring and reporting. The NEMaR framework is similarly based on assessing EI, but at this stage the scope of the framework is narrower, being predominantly focused on water quality related indicators. Both the CDRP and NEMaR framework also lacked a wetland component. The DOC Arawai Kākāriki wetland monitoring framework is quite comprehensive (for palustrine wetlands) and closely tied with the original Lee et al. (2005) framework. The wetland condition framework is not as comprehensive, but represents a good working example of how indicators covering a wide array of EI components can be integrated in assessing ecosystem condition holistically.

3. Proposed Tier 1 framework and indicators

Information from the four frameworks were used in developing a revised biodiversity monitoring framework from Lee et al. (2005) including new measures for rivers, lakes and wetland environments (Table ES1). The framework consists of 32 freshwater measures covering 13 indicators related to the three targeted national outcomes. These cover a wide range of indicator types including productivity, water quality and yield, ecosystem disruption, contaminants, exotic weeds and pests, conservation status of species, occupancy range of species, environmental representation and protection status, and biological responses to climate change. The amended framework includes a more comprehensive range of freshwater measures, but is compatible with the monitoring and reporting indicators framework being used by DOC for terrestrial Tier 1 biodiversity monitoring and reporting.

4. Existing freshwater monitoring to inform the proposed framework

The Department of Conservation presently monitors approximately 2,000 sites for freshwater biodiversity and biosecurity purposes. Approximately 350 sites are threatened for species monitoring developed in association with species recovery plans. Freshwater biosecurity surveillance monitoring is conducted by DOC at approximately 1,500 sites mostly in regards to pest fish species, but more recently monitoring for the presence of the invasive algae Didymosphenia geminata et al. (2005) framework indicators on water quality and yield (1.3), some information related to river productivity (1.2) and community composition (5.1) could also be applied to reporting on Lee et al. e.g. fish community, aquatic plants) to be more applicable for DOC's biodiversity reporting purposes. These networks are also limited in coverage of river environment types, and bias towards sites within agriculturally (2005) indicators. However, monitoring is predominantly focused on water quality, and would require a greater number of biological measures (at just under 500 sites. While some of the monitoring is at regular intervals using set protocols, much of it is not a part of routine monitoring programmes so would need to be revised significantly to fit a Tier 1 monitoring programme.

The National River Water Quality Network (NRWQN) operated by NIWA, and regional councils and unitary authorities conduct significant river monitoring. This includes over 1,000 sites for water quality, 300 sites for macroinvertebrates, 930 sites for periphyton, and 171 sites for fish. The combined NRWQN and council monitoring information would provide reasonably robust information for wadeable rivers in regards to the Lee et al. (2005) framework indicators on water quality and yield (1.3), some information related to river productivity (1.2) and community composition (5.1) could also be applied to reporting on Lee et al.e.g. fish community, aquatic plants) to be more applicable for DOC's biodiversity reporting purposes. These networks are also limited in coverage of river environment types, and bias towards sites within agriculturally (2005) indicators. However, monitoring is predominantly focused on water quality, and would require a greater number of biological measures (e.g. fish community, aquatic plants) to be more applicable for DOC's biodiversity reporting purposes. These networks are also limited in coverage of river environment types, and bias towards sites within agriculturally dominated catchments with limited network coverage of public conservation lands, one of the primary objectives of the Tier 1 programme.

Approximately 112 lakes are monitored nationally by regional councils for water quality (between 2005–2009) and at present 200 lakes nationally have had aquatic macrophyte assessments using the LakeSPI methodology. This monitoring could enable reporting in regards to water quality and yield (1.3.), and some information related to lake productivity (1.2) (planktonic, macrophytes). Additionally, some data on macrophyte community composition could also be applied to assessment of ecosystem composition (5.1), and new weed species and weed dominance (2.1 and 2.2). Lake monitoring is biased towards medium and larger sized lakes, and similar to river monitoring, occurs mostly outside of public conservation land limiting the ability to report on status and trends within PCL.

DOC presently conducts routine monitoring of a small number of wetlands nationally, and number of regional councils have recently established, or are in the process of establishing, wetlands monitoring programmes. A revised terrestrial monitoring framework to be applied by councils was developed recently in a workshop process between councils, central government, and Landcare Research (Lee & Allen 2011). The adoption of such a framework by councils would have the potential to enhance wetland biodiversity reporting, but at this time only a limited number of councils are implementing specific wetland monitoring. The extent of wetland monitoring is therefore insufficient to underpin national reporting in a Tier 1 programme, and would need to be expanded significantly to achieve this objective.

Tier 1 implementation process

Taking account of other agency freshwater monitoring, especially biodiversity focused sampling; we recommend that the DOC Freshwater Tier 1 programme concentrates on freshwater ecosystem monitoring that enables a good estimate of EI while capturing key aquatic biodiversity metrics such as species abundance and diversity. Wetlands monitoring is viewed as a key priority, with DOC taking a national lead on mapping, assessing (WONIFENZ) and now monitoring (Arawai Kākāriki). DOC has traditionally put significant effort into freshwater fish monitoring, and some of these datasets are the longest running sets in New Zealand. Therefore these are two areas that would meet primary management objectives of DOC, and fill gaps in current ecological monitoring, and provide good linkages with other monitoring agencies. Similarly, a targeted programme across lakes, rivers and wetlands could occur if only a limited set of measures were applied, and integration with monitoring networks overseen by other agencies (e.g. regional councils, NRWQN).It is anticipated that a pilot, or several pilot studies, be investigated around the design and implementation of a Tier 1 network, considering various attributes for design of a statistically robust network of sites. This would include metrics used to inform indicators and measures, field survey and laboratory methodologies, sampling design, and statistical analyses to inform reporting on indicators. The type of pilot would very much depend on the focus area of the Tier 1 programme, as presently there are very different quantities of existing environmental data to inform EI indicators for rivers, lakes and wetlands. The scale and location of the pilot, inclusion of partners in monitoring, and decisions on departmental expertise, are required to get accurate estimate of costs of a monitoring network, which will be a key aspect in its implementation. It is anticipated this pilot process will be in conjunction with a consultation process with key stakeholders within DOC and other central government agencies (e.g. MfE, MPI), and potential partner monitoring agencies (e.g. regional councils).