Background

This measure relates to indicator 1.4.2 – Security of threatened and at-risk taxa.

Aotearoa New Zealand’s native species and the ecosystems they inhabit are vulnerable to many threats that must be managed to ensure we maintain our natural heritage. Each year, DOC identifies the conservation management needs of native species (or other taxon levels such as subspecies) and then evaluates whether these needs have been effectively met to ensure ‘long-term persistence’ of species.

157 species had management that met standards for long-term persistence.

What did we measure?

Summaries were produced by combining three types of records.

  • The conservation status of each species as at May 2023, 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 in 953 ecosystem and species management units that were active in the 2022/23 financial year

We then evaluated how many species had management that met the criteria of the following categories.

  • Any management at any site
  • Management that met the exact or 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 exact or 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: Data from monitoring threatened species populations in the wild were not incorporated into this analysis.

What did we find?

  • 453 Threatened species may benefit from some form of management in at least one site2 (Table 1). A further 303 ‘Other’ (At Risk or Conservation Dependent as classified by the NZTCS) species may benefit from some form of management in at least one site making a total of 756.
  • Of the 756 species receiving some form of management, 157 were adequately ‘managed for persistence’. This means they received management that met their exact requirements in at least 90% of the sites recommended by experts to ensure their long-term persistence. This group comprised 79 Threatened species and 78 Other species.
  • 471 species received management that met their approximate requirements in at least one site. This group comprised 272 Threatened species and 199 Other species.
  • 8 out of 23 taxon groups contain species that were managed for persistence (have their exact management needs met in at least 90% of sites recommended by experts) (Figure 1).
  • The number of species under management this year is slightly higher than that reported last year (751 species were reported as receiving some form of management and 116 species were reported as receiving full management in at least 90% of sites in 2021/22). The main reason for this is that last year, species that relied on the pest-free status of Manawataawhi (Three Kings Islands) were not classed as fully managed because there was no biosecurity surveillance work carried out on the islands. This work was temporarily paused and was reestablished in 2022/23 so these species are considered fully managed again.
Table 1: Number of species managed to different degrees of the required standards for long-term persistence according to conservation status
Conservation status Any management at any site Management to exact or approximate standard at any site Management to exact standard at any site Management to exact or approximate standard at ≥90% of required sites Management to exact standard at ≥90% of required sites
Threatened 453 272 232 100 79
Other 303 199 183 95 78
Total 756 471 415 195 157
Note: Species counted in columns with management that more closely met the required standards are also counted in other columns, therefore rows cannot be summed
Total N = 220Total N = 430Total N = 670Total N = 509Total N = 202Total N = 161Total N = 68Total N = 110Total N = 2744Total N = 4Total N = 5Total N = 220Total N = 430Total N = 51Total N = 670Total N = 761Total N = 509Total N = 202Total N = 45Total N = 99Total N = 161Total N = 68Total N = 110Total N = 1095Total N = 25Total N = 2744Total N = 12Total N = 220Total N = 430Total N = 237Total N = 177Total N = 51Total N = 670Total N = 137Total N = 761Total N = 144Total N = 509Total N = 202Total N = 45Total N = 99Total N = 563Total N = 110Total N = 1095Total N = 2744Total N = 4Total N = 12Total N = 5Total N = 220Total N = 430Total N = 237Total N = 177Total N = 51Total N = 670Total N = 137Total N = 761Total N = 144Total N = 509Total N = 202Total N = 45Total N = 99Total N = 563Total N = 161Total N = 68Total N = 110Total N = 1095Total N = 25Total N = 274400.20.40.60.81AmphibiansAphidsBatsBirdsColeopteraDipteraEarthwormsFreshwater fishesFreshwater invertebratesHemipteraHornworts and liverwortsHymenopteraLand snailsLepidopteraMinor invertebrate groupsMossesNematodesOrthopteraPowelliphantaReptilesSpidersStick insectsVascular plants
Management requirements Unknown/undocumented/unrequiredDocumented but unmetDocumented and partially metDocumented and adequately metProportion

Figure 1: Proportion of species in each group that need conservation management and have their management needs 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 New Zealand’s Environmental Reporting Series.

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. 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 DOC collates about species management needs.

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 species groups.

There is uncertainty about whether the actions described and funded for each ecosystem or species management unit were delivered to standard and met desired targets for threat (or pressure) reduction.

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 Aotearoa 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 (eg 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 (ie 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/levels, such as subspecies.

  1. 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.↩︎

  2. This management is not always specifically targeted to the species’ requirements but rather aims to maintain ecosystem health and function.↩︎