Understanding New Zealand Drylands: Conservation Challenges & Initiatives

1. What are drylands? Background information for a meeting to discuss drylands in the revised Otago CMS Grant Norbury and Susan Walker Landcare Research, Dunedin and Alexandra April 2010

2. Drylands: Contain some of the most transformed, least protected and most threatened native ecosystems and species in New Zealand Are unstable, seral, rapidly changing, invaded

3. In seeking to protect and restore drylands, we face: Limited knowledge, experience and science to support biodiversity managers Poor agency and community awareness of dryland biodiversity and its protection needs

4. A first attempt to define a New Zealand Dryland Zone Rogers et all (2005) Science for Conservation. http://www.doc.govt.nz/upload/documents/science-and-technical/SFC258.pdf Area ~ 50,500 km2

5. B. North Island Hill Country Relatively moist (high rainfall: potential evapotranspiration ratio) environment with infertile soils, often derived from younger sedimentary rocks such as mudstones andsiltstones. A. Gisborne-Hawke’s Bay This is the most northerly group of dryland environments. On average, they experience the most variable rainfall, the least severe and latest frosts, the highest winter and summer solar radiation, and the highest mean annual temperatures. Dryland “Types” (including Manawatu) D. Coastal Marborough – Kaikoura Coast – inland North Canterbury The driest and sunniest dryland environment type, experiencing the highest atmospheric and soil moisture deficits and the highest average summer solar radiation. Soil fertility is generally high, and there are few chemical limitations to plant growth. D. Coastal Marborough – Kaikoura Coast – inland North Canterbury The driest and sunniest dryland environment type, experiencing the highest atmospheric and soil moisture deficits and the highest average summer solar radiation. Soil fertility is generally high, and there are few chemical limitations to plant growth. “Types” are defined based on environmental factors only (not plants and animals) C. Wairarapa – Wellington Coast – Nelson - Manawatu Typically comprising young, fine sediments, often poorly drained substrates with saline chemical limitations to forest growth, low atmospheric andsoil moisture deficits. C. Wairarapa – Wellington Coast – Nelson. Typically comprising young, fine sediments, often poorly-drained substrates with saline chemical limitations to forest growth, low atmospheric and soil moisture deficits. E: Marlborough – North Canterbury The highest-elevation group of dryland environments, including relatively steeply sloping, well-drained foothills of the Marlborough and North Canterbury mountain ranges, characterised by high atmospheric moisture deficits. Older substrates predominate, and calcareous younger sedimentary rocks and older sedimentary rocks (e.g argillite) feature strongly. The Units we grouped into “Types” are (LENZ Lvl IV) land environments F: Canterbury Plains and Otago inland basin alluvium and loess These environments combine low temperatures and low solar radiation inputs, which reflect southern latitude, with characteristic alluvial and loessial substrates. H: Mackenzie Basin and Central Otago This group of environments covers the steeply sloping foothills of these basins, and is characterised by low atmospheric water deficts, low mean annual temperatures, low solar radiation inputs, and severe, early winter frosts, all reflecting southern latitude. Soils are often alluvial, and predominantly derived from schist. G: Inland southern South Island basins and valley floors This group of environments is highly variable, and distinguished by high elevation, severe frosts, low mean annual temperatures, low solar radiation inputs and relatively consistent annual rainfall. Soil moisture deficits are high, but atmospheric water deficts tend to be low. Soils are generally schist and alluvium derived and relatively fertile (with high acid-solublephosphate). G: Inland southern south island basins and valley floors Complex of Nine groups, highly variable, cool, with v. variable moisture regimes and substrates. Most totara, fairly high notsol, 6.Mat & 7.Hall (share high with H), High Comp1 (share high with H), southerly, low mat, low junes, lwo decsol, highest jdgfrost, among earliersty fafrost, lowest rnvar, r2pet, among highest pendef (but low octvpd), high acidp, high sc (but not as high as h), among highest al, highest elev.

6. 43.7% cleared 83.4% cleared REST OF NZ DRYLANDS TOTAL NZ LAND AREA Area ~ 50,500 km2 Dryland ecosystems have been extensively cleared 19.4% DRYLAND REMAINING PREDOMINANTLY INDIGENOUS ECOSYSTEMS

7. 2.4% protected 38.1% protected REST OF NZ DRYLANDS TOTAL NZ LAND AREA Area ~ 50,500 km2 And have extremely poor protection 19.4% DRYLAND AREA LEGALLY PROTECTED (COVENANTS, DOC etc)

8. 41.7% DRYLAND 32.4% DRYLAND ACUTELY THREATENED PLANTS CHRONICALLY THREATENED PLANTS TOTAL NZ LAND AREA Area ~ 50,500 km2 But support high proportions of NZ’s most threatened plants, invertebrates and lizards 19.4% DRYLAND PROPORTION OF NZ’s MOST THREATENED PLANTS NB lists & %s not updated to Townsend et al 2008/ de Lange et al 2009!

9. Acutely Threatened Chronically Threatened At Risk DRYLANDS: 226 THREATENED PLANTS ALL of NZ: 1000 THREATENED PLANTS TOTAL NZ LAND AREA Area ~ 50,500 km2 More threatened than average 19.4% DRYLAND THREAT CATEGORIES (PLANTS)

10. Drylands in Otago Conservancy DOC Area % Dryland Central Otago 69.7 Wanaka 30.3 Coastal Otago 26.2 Wakatipu 16.0

11. Drylands in Otago Conservancy • H: Southern dry hill country • Mainly steep foothills of the basins • inland, so high elevation • cool, severe frosts, low solar radiation • But smaller soil moisture deficits than G • Schist-derived soils • G: Inland southern South Island basins and valley floors • Highly variable, but distinguished by: • inland, so high elevation • cool, severe frosts, low solar radiation • Big soil water deficits, BUT low air water deficits • Fertile schist and alluvium-derived soils

12. REMAINING PREDOMINANTLY INDIGENOUS ECOSYSTEMS AREA LEGALLY PROTECTED (COVENANTS, DOC etc) G: Inland southern South Island basins and valley floors H: Southern dry hill country

13. G: Inland southern South Island basins and valley floors

14. G: Inland southern South Island basins and valley floors

15. H: Southern dry hill country

16. H: Southern dry hill country

17. Drylands All of NZ Acutely Threatened Chronically Threatened At Risk Critically Underprotected Underprotected No threat category

18. Threatened environments • Combination of 3 national datasets • Divides country into 6 threat categories based mainly on: past loss of indigenous vegetation (% indigenous cover left) but also on: current legal protection (% protected)

19. Threatened environments based on indigenous cover left, no matter how much protected based on indigenous cover left (>30%) left AND how much protected

20. Drylands only Otago

21. Otago Conservancy’s Threatened Environments New Zealand Otago Conservancy as a whole Environment Threat Categories (Proportion Land Area)

22. This Region’s Threatened Environments New Zealand Otago DRYLANDS Environment Threat Categories (Proportion Land Area)

23. Drylands only