WHAT IS SPECIAL ABOUT WHAT IS SPECIAL ABOUT NELSON S BIODIVERSITY - PowerPoint PPT Presentation

WHAT IS SPECIAL ABOUT WHAT IS SPECIAL ABOUT NELSON’ ’S BIODIVERSITY S BIODIVERSITY NELSON and where is it going? by Shannel Courtney Department of Conservation, Nelson

Nelson City Nelson City

Nelson’s Coastal Ecosystems Nelson’s Coastal Ecosystems • extensive coastline • wide variety of coastal systems – very sheltered to very exposed – range of substrates, landforms, array of coastal processes • parts of which are nationally and regionally important for biodiverstiy

Nelson Boulder Bank Nelson Boulder Bank

Boulder Bank Community Boulder Bank Community spotted skink porcupine shrub

Boulder Bank underwater Boulder Bank underwater communities communities • sponge beds • horse-mussel beds

Estuarine Ecosystem Estuarine Ecosystem back beach beetle native musk bar-tailed godwit

Dunelands Ecosystem Dunelands Ecosystem katipo pingao

Mineral Belt Ecosystem Mineral Belt Ecosystem mini gecko mineral belt forget-me-not

Limestone belt Ecosystem Limestone belt Ecosystem Limestone belt Ecosystem Limestone belt Ecosystem

Limestone belt Ecosystem Limestone belt Ecosystem limestone kowhai limestone three finger

River Ecosystems River Ecosystems – relatively big rivers – collectively retained cf. those of NZs most of their native largest cities fish fauna – still have tracts of – important habitat native riparian for several vegetation threatened species – drain hard rock substrates and headwaters are vegetated: good water quality in upper reaches

Freshwater wetland Ecosystems Freshwater wetland Ecosystems • naturally few freshwater wetlands in Nelson • most are coastal and associated with river mouths, estuaries, dunes and boulder beaches •provide important refuges for wetland species

Forest Ecosystems Forest Ecosystems • Nelson still retains some significant tracts of coastal and lowland forest (unlike many cities) • special vegetation types – matai – black beech forest – tanekaha – southern rata forest • 17 species of nationally threatened plants • national stronghold for several species – shovel mint, mineral belt endemics • species limits and northern elements – southern limits for NI species (tanekaha, pukatea, kohekohe, tawa, black maire) – western limits for Sounds species (ramarama, leafless bushlawyer)

Where is our native Where is our native biodiversity going? biodiversity going?

• Need to know: • what Nelson’s past biodiversity was like, • how it differs from today’s, • the factors that contributed to how it got to what we have today

What did Nelson City originally What did Nelson City originally look like? look like? • Most of the Nelson region below 1200m (treeline) was covered in tall forest. • Open areas were uncommon and confined to river beds and deltas, wetlands, estuaries, dunes, bluffs, and the Nelson mineral belt. • The Region was teaming with wildlife – birds, lizards, bats, insects and seals.

Nelson Haven – 1200 AD?

Pepin Island, 1200 AD? Pepin Island, 1200 AD?

Rocks Road, 1200 AD? Rocks Road, 1200 AD?

Maitai River mouth – – 1200 AD? 1200 AD? Maitai River mouth

giant weta hamilton’s frog tuatara striped gecko

Nelson City 1842 Nelson City 1842 John Saxton sketch

Forest loss in Nelson Region - - 2005 2005 Forest loss in Nelson Region Cleared lowland forest Remaining lowland forest Cleared upland forest Remaining upland forest Non-forest ecosystems (alpine, dunes, mineral belt, estuaries, bluffs, boulder bank, river beds)

Native Vegetation Loss in Nelson Native Vegetation Loss in Nelson City - - 2005 2005 City Nelson City boundary Cleared lowland forest Remaining lowland forest Cleared upland forest Remaining upland forest Non-forest ecosystems (mineral belt, estuaries, boulder bank, bluffs)

Natural Areas protected for Natural Areas protected for biodiversity in Nelson City biodiversity in Nelson City Nelson City boundary Cleared lowland forest Protected lowland forest Cleared upland forest Protected upland forest Non-forest ecosystems (mineral belt, estuaries, boulder bank, bluffs)

Native Vegetation Loss in Nelson Native Vegetation Loss in Nelson City City 100% 90% native 80% vegetation 70% lost 60% 50% native 40% vegetation 30% remaining 20% 10% 0% upland (>600m) total coastal & lowland (<600m)

Native Vegetation Loss in Nelson Native Vegetation Loss in Nelson City City 100% native 90% vegetation 80% lost 70% 60% native 50% vegetation 40% remaining - 30% unprotected 20% 10% native 0% vegetation coastal & upland total remaining - protected lowland (>600m) (<600m)

Native Lowland Vegetation Loss in Native Lowland Vegetation Loss in Nelson City Nelson City 100% 90% 80% 70% native 60% vegetation 50% lost 40% 30% native 20% vegetation 10% remaining 0% estuaries coastal coastal hill lowland lowland hill flats country flats country

Underwater communities Underwater communities • lost bryozoan and fingersponge reefs • depletion of top predators: blue cod, crayfish, terakihi, snapper • Ecklonia kelp beds almost gone

Estuarine communities Estuarine communities

Seabird turf community Seabird turf community

Native dune community Native dune community

Riverine & wetland communities Riverine & wetland communities

Alluvial forest communities Alluvial forest communities

Lowland hill country forest Lowland hill country forest communities communities • weedy • fragmentated • small • vulnerable to stock and • not regenerating animal pests

Conservation status of animals & Conservation status of animals & plants native to Nelson City plants native to Nelson City 100% 90% extinct 80% 70% gone from Nelson City 60% loss from Nelson City 50% imminent 40% populations stable 30% 20% 10% 0% native birds native reptiles native fish native plants (99) & frogs (15) (17) (545)

Blue duck EXTINCT IN NELSON CITY Fernbird ONE POPULATION LEFT IN NELSON CITY

Australasian bittern NO BREEDING POPULATIONS IN NELSON CITY Banded rail LOW NUMBERS & DECLINING IN NELSON CITY

NZ falcon LOW NUMBERS & DECLINING IN NELSON CITY South Island kaka NO BREEDING POPULATIONS IN NELSON CITY

NZ Grayling EXTINCT EXTINCT Brown IN mudfish NELSON CITY ONE KNOWN Giant POPULATION kokopu IN NELSON CITY

Nelson green gecko LOW NUMBERS & DECLINING IN NELSON CITY

Giant flax weevil GONE FROM NELSON CITY

Swamp maire Swamp maire

shovel mint (Scutellaria novae shovel mint (Scutellaria novae - - zelandiae) zelandiae) •nationally endangered •confined to alluvial forest •known only from 12 sites in Nelson & N. Marlborough •1 site left in Nelson City

Future A - - Future A based on past and present trends based on past and present trends continued: • regional exinctions of native species • increased number of nationally and regionally endangered species and communities • attrition and loss of natural and semi-natural areas • increase in natural area fragmentation • decrease in natural area buffering from the working landscape • decrease in natural area structural diversity and species diversity, eg lowland old growth forest gone • increase in extent and no. of weed & animal pest species • decrease in natural area quality and integrity due to weeds and animal pests

Future A - - Future A based on past and present trends based on past and present trends • decrease in the rate of natural area loss • increase in no. of restoration initiatives • increase in legal protection for biodiversity, including marine reserves

Future B – – encouraged by a encouraged by a Future B biodiversity strategy biodiversity strategy Active restoration initiatives: • The Brook, Whakapuaka, Paramata Flats, and Maitai- Roding Water Reserve as sanctuaries • Connecting and enlarging fragmented natural areas • Creating and enhancing riparian corridors along streams and rivers • Increasing water quality and restoring the structural quality of our waterways • Connecting coastal and inland ecosystems • Creating new natural areas (especially of extinct or rare ecosystems) • Creating marine reserves, taiapure, mataitai

Future B – – provided for by a provided for by a Future B biodiversity strategy biodiversity strategy • For species and habitats: • improving biosecurity and border control measures • getting serious about weed and animal pest control • restoring habitats for threatened species • re-introducing native species • adopting the principle of eco-sourcing to maintain the distinctiveness and genetic integrity of Nelson’s native plants and animals