skip to main content

BiodiversityRerenga rauropi

Biodiversity is one of the four key focus areas for Hawke's Bay Regional Council. We are working towards halting biodiversity decline and envisioning a new hope for biodiversity in Hawke’s Bay.

We’re passionate about protecting Hawke’s Bays’ unique biodiversity so it can thrive.

What is Biodiversity?

Biodiversity is the huge variety of living things and how they are all connected, including plants, animals, and micro-organisms as well as the ecosystems where they live.

Biodiversity can be of any scale – it could be a patch in your backyard or a whole continent. It’s everything from algae in our ponds and lakes, to the huge whales that travel out in Hawke Bay. Our indigenous biodiversity, made up of our native species, their genetic diversity, and the habitats and ecosystems that support them, is of huge value to New Zealanders, our economy, our quality of life, and our sense of identity as a nation.

Sadly biodiversity is in decline across New Zealand, and it’s one of Hawke’s Bay Regional Council’s focus areas.

Find out more about biodiversity and our staff who are passionate about this work.

 

The region was mapped for potential ecosystem types (i.e. pre-human inhabitation) using the latest ecosystem classification system developed by the Department of Conservation. Classification is based on climate and geology (including substrates and susceptibility to waterlogging), but also takes into account a known influence of volcanic (and glacial, if present) activities. A range of other existing documentations were deployed to create a comprehensive spatial layer of the ecosystem pattern.

The resulting map shows the pattern of terrestrial ecosystems that should occur under certain environmental conditions. 61 potential ecosystems types are mapped.

This base layer was intersected with the Land Cover Database (LCDB 4.0) and indigenous land cover types were extracted to estimate the remaining areas of each ecosystem type.

There are 4970,000 ha of indigenous terrestrial areas left in the region, which includes 59 ecosystems types. 22 of these ecosystems are threatened (less than 30% of original area left), mostly of lowland forest types, coastal and dune vegetation types, braided riverbed vegetation, and wetlands. Two ecosystem types were presumed extinct (one lowland forest type and one wetland type) whose historic extents were very small.

Ecosystem Prioritisation is undertaken using Zonation, a tool (software) that prioritises ecosystem or habitat sites based on their representation (i.e. ecosystem types for terrestrial and rivers, and geomorphic types for lakes), connectivity (with other terrestrial sites and/or aquatic ecosystems) and conditions.

Zonation-based prioritisation has been adopted by a number of regional councils and Department of Conservation. It requires ‘a cap’ in which it produces the best set of sites to achieve full representation. It is generally an area-based cap which is set by asking ‘of the remaining indigenous ecosystems, how much area can we manage within a given timeframe?’

For the Hawke’s Bay, we have set the cap of 30% (of the 497,000 ha of indigenous areas remaining) by 2050. The principle behind the 30% is the species-area curve, i.e. when habitat (or a population) is reduced to 20% of the original extent (or a population), the rate of species loss is exponentially accelerated. Therefore 30% was chosen as a reasonable target that balances species response with achievability and affordability.

The scope of the Zonation-driven prioritisation included terrestrial ecosystems (including wetlands and braided riverbeds), lakes and streams. Although ranking was done separately for the three ecosystem domains, ranking of terrestrial ecosystems reflects the connectivity with lakes and/or streams. For example, if there are two sites representing the same ecosystem type, but one intersects with high ranked streams and the other doesn’t, Zonation will rank the former higher as it would account for the connectivity of the terrestrial ecosystem with the river ecosystem.

Zonation identified 900 terrestrial sties (150,000 ha), 10,034 segments of streams (6,700 km), and 77 lakes (1,700 ha) as the top 30% priority. These sites/segments represent a full range of ecosystem types that are present in the region.

529 of the 900 priority terrestrial sites are less than 10 ha in size. Many of these small sites represent threatened ecosystem types whose remnants are becoming scarce, smaller, more fragmented and isolated. The majority of these sites are on private land.
Interpretation of the Zonation output has been done in collaboration with local experts with ecological and site knowledge, and involved verification of the ecosystem types and reviewing the boundaries indicated by the Zonation.

As mentioned earlier, the ranking of terrestrial ecosystem sites takes into account the connectivity to streams and lakes. Many of the top 30% terrestrial sites adjoin to, or contain highly ranked river segments and lakes. Given the very large volume of river segment and lake sites which are ranked top 30%, staff propose that they do not review river/lake sites individually. If significant values associated with river/lake sites that are not currently associated with the top 30% terrestrial ecosystem sites, they will be added.

As with any modelling tool, Zonation has limitations which need to be considered in the decision making process.

Ecosystem-based site prioritisation is a critical first step to achieving the Biodiversity Strategy objectives and outcomes of sustaining, protecting, and improving the full representation of native species and habitats. It is intended that the Ecosystem Prioritisation will form part of the conversation and decision making by groups and organisations across Hawke’s Bay.

The Ecosystem Prioritisation framework will become an integral part of integrated catchment management. Priority sites that are identified in catchments of interest could also be part of the solution to address issues such as soil/wind erosion and water quality. This is because these remnants are providing ecosystem services such as soil conservation and water retention at a varying degree depending on the their condition. These remnants are also proof that the ecosystem is resilient to the ecosystem is resilient to the condition of the site, and could be capitalised upon by afforestation as part of integrated catchment management. 

 

We’re working across these sites this year to protect and enhance our biodiversity:

  • Birch Hill in Pōrangahau will be one of the largest protected black beech remnants on private land in Hawke’s Bay.
  • Motumokai Bush in is a titoki podocarp remnant with 65 native plants including the Northern rātā
  • Puahanui Bush in Tukituki is considered the largest, most intact, and diverse lowland forest left in Hawke’s Bay
  • Gillies Bush is a 32ha old growth Tawa, titoki, podocarp forest and one of the last forest remnants on the seaward face of the Maraetōtora plateau
  • Pakuratahi Bush in the Waikari catchment is a 80ha remnant is of Tōtara tītoki forest which is acutely threatened in Hawke’s Bay.
  • Lochinvar remnant in Mohaka catchment is two small remnants that contain the nationally vulnerable pittosporum turnerii
  • Whittle Bush is an 84ha kahikatea, rimu forest in the Tūtaekurī catchment that was purchased by council’s Open Spaces team in 2020. The type of forest (MF11-4) is classified as chronically threated

Protecting Our Biodiversity 

Download our biodiversity information sheet here.

Projects & useful links

Find out about some of the Biodiversity work we are involved with.

Little Bush in Puketitiri is a 12ha remnant of kahikatea, rimu forest which has a regional classification of chronically threatened. It is owned by Forest and Bird who have done an inspirational job of restoration planting, weed control and predator management. Stock have been excluded for many years but unfortunately feral deer are having a destructive impact on the bush. Hawke’s Bay Regional Council has partnered up with Forest and Bird and Biodiversity Hawkes Bay in deer fencing this covenant to help protect this precious biodiversity reservoir for future generations to enjoy.

IMG 0955IMG 0951

A wetland gem hidden in a pine forest

Pan Pac Forest Products Limited manages a Kaweka Forest block that is home to the 15-hectare wetland called Pan Pac 15.0. The wetland is considered very healthy and its dominated by native plants, such as Machaerina sedges and manuka, that support native wildlife. This wetland is also one of the places that you are likely to hear or see fernbirds, an ‘at-risk’ declining species threatened by habitat loss and predation.  They are cryptic birds with a fern-like tail and they love thick, wetland vegetation where they fly through with ease.

Since November 2017, Pan Pac has run 126 predator traps in this area, catching hundreds of mammalian predators and allowing fernbirds and other native wildlife to thrive. This predator control effort has enabled the Department of Conservation to release a kiwi chick named ‘Pai’ into the Pan Pac 15.0 wetland last year.

With support from Hawke's Bay Regional Council, Pan Pac also carried out plant pest control in late 2018, targeting weeds such as crack willow, Himalayan honey suckle and Contorta pine, from within and around the wetland. These species pose major threats to the health of a wetland because they are able to establish and dominate areas rapidly while outcompeting native plants for resources.

Wetlands are one of the most threatened ecosystems in New Zealand and only 2% of Hawke’s Bay’s original wetland network remains intact. The areas are highly susceptible to weeds, browsing (mostly from deer) and predation. Pan Pac 15.0 is one of the very few wetlands where native plants and wildlife continue to thrive and we look forward to continuing our work with Pan Pac to ensure the area remains diverse.

DOC kiwi release in kaweka2

 

Pan Pac 15.0 a large wetlandFernbird best pic by Nathan Burkepile

 DOC kiwi release in kaweka5

 

Rarer than you think – Tukituki River mouth

Where the Tukituki meets the ocean, there is a mosaic of estuarine wetlands, shingle beach, riparian forest (at the moment dominated with exotic trees) as well as the powerful braided freshwater river itself .  Both estuarine wetland and shingle beach are rare ecosystems in New Zealand, due to either human activities (such as land reclamation and conversions) or being historically (i.e. naturally) rare.

A small area of wetland vegetation (photo of turf community), full of unique, low-stature plants such as native musk and Triglochin striata, still remains in the relatively weed-free mudflats of the Tukituki River mouth.

Also thanks to such a diversity of ecosystems, the area is home to a wide range of New Zealand birds such as  black-billed gulls, white-fronted terns, and New Zealand dotterel.  Many of these species have ‘Threatened’ status because of habitat loss and predation 

In summer 2017, one of the largest breeding colonies of black-billed gulls was nesting in the area .  With the help of Bernie Kelly, a Birds NZ – HB representative and Clive resident, predator trapping was carried out in the area and the benefits are ongoing.

But there are a few issues that are threatening these rare ecosystems.  As well as the constant pressure from mammalian predators, the area is has become infested with plant species such as silver poplar, old man’s beard, and periwinkle.  HBRC have started removing the silver poplars on both sides of the river mouth.  The Council will also be shaping an unstable bank on the Haumoana side to create a better habitat for inanga spawning.  Inanga already favour the area for spawning and by trimming the Ngaio trees, to provide more light at ground level, dense grass growth will improve spawning habitat.

This is the beginning of long journey to protect and enhance this special area.

White fronted ternTurf community can be found on weed free mudflatTukituki River mouth aerial view mosaic of different ecosystems by B. StephensonShingle beach supports many seabirds


Black billed bull adult by Natalie

 

The Mediterranean fanworm and Clubbed tunicate are marine pests which can both form colonies of very high densities competing with native species for food and space. Their impact on native species and habitats means they pose a significant risk to Hawke’s Bay underwater reefs, and to commercial and recreational fishing, and shellfish harvesting. The main way these are spread into new locations is through hull fouling on boats. It is crucial that these marine pests are kept out of Hawke’s Bay waters to maintain the marine biodiversity here.

A recent dive survey of the Ahuriri Inner Harbour recently has given an ‘all clear’ on marine pests that we don’t want to see in Hawke’s Bay coastal waters. The next survey of the Napier Inner Harbour for marine pests will be in 2 years time.

The new Regional Pest Management Plan that was implemented on 1 February 2019 and specifies these creatures as Exclusion Pests – in other words, they aren’t found here and they need to be kept out of Hawke’s Bay waters.  They have established in some areas in New Zealand, but are not known to be present in the waters of Hawke’s Bay, although the risk of them getting here remains.

Because Mediterranean fanworm and Clubbed tunicate have been declared as Exclusion Pests, it allows the Regional Council to act immediately if either of these species are found within Hawke’s Bay Regional Council waters.

Hawke’s Bay Regional Council is part of the North Marine Biosecurity Partnership with 6 other regional and unitary councils, sharing knowledge and expertise.

Find out more about Marine Pests here.

Fanworm in water 2 credit NRC

The Whangawehi river is tucked away in a remote corner in Mahia Peninsula. This community project is looking at protecting and enhancing the Whangawehi Catchment. The project is run by the Whangawehi Catchment Management Group (WCMG) to help restore the streams that flow into the Whangawehi river. 

Over the last 6 years there has been much work carried out, including:

  • Fencing – the river is now nearly completely fenced off
  • Retiring land – 65 hectares of land bordering the river has been retired from farm use.
  • Trees – 165,000 trees planted

The results are:

  • Native Fish – The river is full of fish and Whitebait and long fin eel populations are exploding.
  • Native plants – In the areas of retired land we’re seeing new native plants taking hold.

The next section of restoration will help to continue to improve water quality, and support flourishing ecosystems and biodiversity.

Te Mangatupae stream is a tributary of our sacred Whangawehi River. The land along its banks needs to be retired from farm use and replanted. 3000 metres of waterway will be planted with 38,000 trees. 

Hawke’s Bay Regional Council are a key funder in this project. However, further funding is needed. You can find out more and donate to this worthy project through the Million Metres organisation here.

 IMG 4703 1 1226x816

Biodiversity Hawke's Bay

Find out more about Biodiversity and the work Biodiversity Hawke's Bay are doing here.

Watch the Biodiversity Hawke's Bay video:

Biodiv logo

We're under threat

  • In New Zealand 75 animal and plant species have become extinct since human settlement. 90% of seabirds and 80% of shorebirds are threatened with or at risk of extinction.
  • Almost two-thirds of New Zealand’s rare ecosystems are under threat of collapse, and over the last 15 years 86 species became at risk of extinction, compared with the conservation status of just 26 species improving in the past 10 years.
  • Approximately 75% of indigenous forest cover has been lost.
  • New Zealand is losing species and ecosystems faster than nearly any other country with four thousand of our native species in trouble.

What we do

We use an ecosystem-based conservation approach to protect indigenous biodiversity. This involves securing, maintaining, and restoring a full range of remaining natural habitats and ecosystems. The approach focuses on habitats and ecosystems as a means of conserving the biodiversity that relies on them. By focusing on natural ecosystems we’re aiming to maintain viable populations of native species. 

Our current focus is to ‘secure from extinction’ 677 sites we’ve selected across the region that are really special. For each site, we work with landowners and groups to create a plan on how to best protect this site, which can include deer fencing, pest control, and replanting.

If you have a natural site on your property that you would like to protect then please contact the Biodiversity Team for further information.

Loading...

Disclaimers and Copyright
While every endeavour has been taken by the Hawke's Bay Regional Council to ensure that the information on this website is accurate and up to date, Hawke's Bay Regional Council shall not be liable for any loss suffered through the use, directly or indirectly, of information on this website. Information contained has been assembled in good faith. Some of the information available in this site is from the New Zealand Public domain and supplied by relevant government agencies. Hawke's Bay Regional Council cannot accept any liability for its accuracy or content. Portions of the information and material on this site, including data, pages, documents, online graphics and images are protected by copyright, unless specifically notified to the contrary. Externally sourced information or material is copyright to the respective provider.

© Hawke's Bay Regional Council - www.hbrc.govt.nz / +64 6 835 9200 / info@hbrc.govt.nz