Number of managed indigenous species
This measure relates to indicator 1.4.2 – Security of threatened and at risk taxa.
Background
New Zealand’s native species and the ecosystems they inhabit are vulnerable to a variety of threats that must be managed to ensure we maintain our natural heritage. DOC identifies the conservation management needs of native species (or other taxon levels) and then evaluates whether they have been managed effectively for long-term persistence on an annual basis.
161 species currently receive adequate conservation managment to ensure their long-term persistence.
What did we measure?
Summaries were produced by combining three types of records.
- The threat status of each species as at April 2020, which was extracted from the New Zealand Threat Classification System (NZTCS) database.
- The locations of populations of species that require management and the threats (or pressures) that must be addressed to ensure their persistence, which were obtained from approximately 80 subject matter experts.
- Management actions to address threats in 833 ecosystem and species management units that were active in the 2019/20 financial year.
We then evaluated the level of management each species received using the following categories.
- Any management at any site.
- Management that met the approximate1 standards indicated by subject matter experts in at least one site identified as critical for persistence of the species.
- Management that met the exact standards indicated by subject matter experts in at least one site identified as critical for persistence of the species.
- Management that met the approximate standards indicated by subject matter experts in at least 90% of sites identified as critical for persistence of the species.
- Management that met the exact standards indicated by subject matter experts in at least 90% of sites identified as critical for persistence of the species.
Note: Quantitative measurements demonstrating outcomes for the population viability of threatened species were not incorporated into this analysis.
What did we find?
- 719 species are likely to benefit from some form of management in at least one site (Table 1).2
- 161 of these species currently receive management that meets their exact requirements in at least 90% of the sites recommended by experts to ensure their long-term persistence, while a further 241 receive such management in at least one site.
- 193 species currently receive management that meets their approximate requirements in at least 90% of the sites recommended by experts to ensure their long-term persistence, while a further 259 receive such management in at least one site.
- 10 out of 23 groups contain species that have their exact management needs met in at least 90% of sites recommended by experts (Figure 1).
- There has been a large increase in the number of species under management this year compared with last year (543 species were reported as receiving some form of management and 102 species were reported as receiving full management in at least 90% of sites in 2018/19). This increase can be explained by improved knowledge and documentation of species management needs and distributions, along with more conservation management actions for biodiversity at place.
| Threat status | Any management at any site | Management to approximate standard at any site | Management to exact standard at any site | Management to approximate standard at ≥90% of required sites | Management to exact standard at ≥90% of required sites |
|---|---|---|---|---|---|
| Threatened | 430 | 256 | 220 | 92 | 78 |
| Other | 289 | 196 | 182 | 101 | 83 |
| Total | 719 | 452 | 402 | 193 | 161 |
Figure 1: Proportion of species in each group that are currently identified as requiring conservation management and have their management requirements adequately met, partially met or unmet. Adequately met means that species received management that met the exact standards indicated by subject matter experts in at least 90% of sites identified as critical for persistence of the species. Partially met means that species received some management in at least one site.
Data quality
This measure is classified as a partial measure and complies with the data quality guidelines used in the Environmental Reporting framework.
It should be noted that the NZTCS is a qualitative process that uses the judgement of subject matter experts to assess the conservation status of a species according to its risk of extinction within New Zealand at 5-yearly intervals. Thus, the quality and availability of scientific information to support the threat listing process varies between species and species groups. Similar limits apply to the advice collated by DOC about species management needs. There is also uncertainty as to whether the actions described and funded for each ecosystem or species management unit in June 2019 were delivered to standard and met desired targets for threat (or pressure) reduction.
DOC has been collating the advice of subject matter experts into a database of species’ management needs since 2014, focusing on groups of species that are relatively well-studied and easily recognised. Some groups (such as fungi, lichens and fleas) remain out of scope. Marine species (other than seabirds) and migratory fishes have also been excluded, as DOC uses other methods for reporting on these taxonomic groups.
DOC is working to continuously improve the information used to report on the number of species under management each year. The implications of this are that changes in the numbers of species under management may reflect true changes in the management of species, or improvements in our knowledge and documentation of species and their management needs.
Glossary of terms
Ecosystem management units (EMUs) are places that have been identified as being important for management as they provide the best examples of the full range of New Zealand’s terrestrial, wetland and lake ecosystems. They may be on land or water of any tenure and often include several connected ecosystems and communities of threatened species.
Long-term species persistence is where there is a 95% probability of a species surviving for the next 50 years or three generations (whichever is longer) if all human-induced threats that are likely to occur over the longer term (e.g. within 300 years) are adequately mitigated. Ensuring the long-term persistence of a population includes all of the components associated with securing a species from extinction, as well as buffering the population against the impacts of loss of genetic diversity, and longer term environmental events, such as climate change. The persistence of a species depends on population viability.
Population viability indicates the ability of a population to avoid extinction. A population is only considered viable where it has an intrinsic ability to increase due to its large size or because recruitment exceeds mortality, and where it is resilient to low and moderate level stochastic events over a 50-year time frame given suitable management. The minimum acceptable level of population viability is the point at which the species has been secured from extinction (i.e. is no longer in decline), key threats are understood and managed, and the population is able to recover given additional management.
Species management units (SMUs) are places that are managed only for the threatened species that inhabit them.
Taxon (plural taxa) is a group of one or more populations of an organism that are considered to form a unit. ‘Species’ is an example of a taxonomic unit. The NZTCS generally assigns conservation statuses to species, but sometimes it is appropriate to recognise other taxonomic units, such as subspecies.
Additional resources
We included approximate standards because for many species there is uncertainty around the exact standards required to meet management needs and how these should be achieved and reported. Approximate standards allow the level prescribed by subject matter experts to be relaxed by one unit. For example, if experts indicated that stoats must be controlled to ‘very low levels’, the standard would be met if they were reported to be controlled to ‘low levels’ only.↩
This management is not always specifically targeted to the species’ requirements but rather aims to maintain ecosystem health and function.↩