Ecosystem Services of Protected Areas and Ecological Corridors Within the Kaimai-Tauranga Catchments
Total Page:16
File Type:pdf, Size:1020Kb
Ecosystem Services of Protected areas and Ecological Corridors within the Kaimai-Tauranga Catchments TECHNICAL REPORT SERIES 2 Ecosystem Services of Protected areas and Ecological Corridors within the Kaimai-Tauranga Catchments Technical report series 2 Astrid van Meeuwen-Dijkgraaf Wildland Consultants Ltd, 7B Sunlight Grove, Elsdon, Porirua 5022 William B. Shaw Wildland Consultants Ltd, 99 Sala Street, P.O. Box 7137, Te Ngae, Rotorua. Federico Mazzieri Wildland Consultants Ltd, 99 Sala Street, P.O. Box 7137, Te Ngae, Rotorua. Published by Department of Conservation East Coast / Bay of Plenty Conservancy PO Box 1146 Rotorua, New Zealand 1 Authors: A. van Meeuwen-Dijkgraaf, W.B. Shaw, F. Mazzieri Wildland Consultants Ltd, 99 Sala Street, P.O. Box 7137, Te Ngae, Rotorua. Cover photograph: View from Ngatamahinerua Plateau, Kaimai-Mamaku Forest Park. P. Cashmore. 2009. © Copyright August 2010, East Coast Bay of Plenty Conservancy, New Zealand Department of Conservation. ISBN (Print): 978-0-478-14823-7 ISBN (Web): 978-0-478-14824-4 ISSN (Print): 1176-276 ISSN (Online): 176-2772 This report was prepared for publication by the Conservation Support Supervisor (Biodiversity) / Conservation Analyst, East Coast Bay of Plenty Conservancy. Publication was approved by the Conservation Support Manager, East Coast Bay of Plenty Conservancy, Department of Conservation, Rotorua, New Zealand. 2 Abstract This study focussed on the catchments that flow into Tauranga Harbour (not including Matakana Island), with a total catchment area of 123,539 ha. Most streams and rivers originate in the Kaimai Ranges, hence the study area is referred to as the Kaimai-Tauranga catchment. It includes parts of four ecological districts: Tauranga, Otanewainuku, Te Aroha, and Waihi. Indigenous vegetation and habitats in the coastal and semi-coastal zones are much reduced from pre-human times. Large tracts of indigenous vegetation remain inland on the Kaimai Ranges. Within the Kaimai-Tauranga catchment, nearly all remaining indigenous vegetation/habitats have been recognised as being of high value. Not all these areas are legally protected. The study area is a population and commercial growth area, and the SmartGrowth Strategy was initiated and adopted by the three councils within the Western Bay of Plenty (Tauranga City Council, Western Bay of Plenty District Council, and Bay of Plenty Regional Council to manage that growth. The SmartGrowth Strategy acknowledges that environmental resources within the Western Bay of Plenty sub-region are finite and must be managed in a sustainable manner for future generations. The aims of the strategy include recognition that there is no further degradation of the environment, indigenous biodiversity is no longer under threat, and there is active enhancement and improvement. Increased land development can, however, have a range of adverse effects on indigenous biodiversity and high value habitats. Mitigation measures and incentives to address some of these effects are discussed. The SmartGrowth Strategy has identified ecological corridors to protect some of the high value ecological sites, and to ensure that ecological processes remain functional and connected between the Kaimai Ranges and the sea. The currently proposed ecological corridors include an additional 5% (2,539 ha) of the study area that is not already legally protected. More ecological corridors may be required in the Tauranga Ecological District, to protect remaining high value sites. Some proposed ecological corridors need to be expanded to include a greater proportion of high value indigenous vegetation. Ideally, the need for ecological corridors should be assessed by sub-catchment, and there are still opportunities to protect high value sites in most sub-catchments. Major rivers and streams, and associated riparian vegetation, are particularly important for ensuring that ecological processes remain connected between inland and coastal high value sites, and also to protect water quality. Coastal habitats also warrant additional protection. Retention (and establishment of) ecological corridors will protect more than just biological diversity. The study area provides a range of recreational opportunities, especially in the Kaimai Ranges. Most of these recreational assets are managed by the Department of Conservation. Ecological corridors and high value ecological sites also contribute to the economic well-being of the study area through ongoing provision of high quality ecosystem services. Ecosystem services are the renewable and non-renewable stocks of natural 3 resources and processes that support life and economic activities. Examples include soil retention and creation, water retention and purification, oxygen generation, air quality enhancements, and food and fuel provision. Very few New Zealand studies of ecosystem services have been undertaken, and it is therefore difficult to accurately assess the value of these services within the study area. An overseas model was used to calculate an indicative economic value for ecosystem services. This model indicated that ecosystem services could amount to $NZ195 million per annum and could contribute about 5% of the sub-region’s GDP annually. The value of potable water resources is a topical issue in many parts of New Zealand, and the study area is no exception, with many waterways providing high quality water to communities, landowners, and commercial enterprises. Some overseas and New Zealand examples of the economic value of water are provided. Within the Kaimai-Tauranga catchment, one quarter of the land is managed by the Department of Conservation. Thus DOC-managed areas are a major source of ecosystem services, provide recreation opportunities, protect threatened species and high value sites, and are key components in the proposed ecological corridors and outstanding natural landscape features. Ongoing protection and enhancement of remaining natural values and resources will require the various land management agencies and the wider community to work collaboratively. Failure to do so will result in ongoing environmental degradation, and the loss of ecosystem services. 4 CONTENTS Abstract 3 1. Introduction 9 2. Project Scope 10 3. Methods 11 4. Ecological Context 12 5. SmartGrowth Strategy 15 6. Protected and Unprotected Natural Areas 19 6.1 Category one natural heritage sites 19 6.2 Areas Identified as ecologically significant in council plans 19 6.2.1 Bay of Plenty Regional coastal Environment Plan 19 6.2.2 Outstanding Natural Features 20 6.2.3 Western Bay of Plenty District Plan 20 6.2.4 Tauranga District Plan 20 6.2.5 Areas Identified as Ecologically Significant in the SmartGrowth Strategy 20 6.2.6 Ecological Corridors 23 6.3 Key Existing Information Resources 27 6.4 National Priorities for protection of rare and threatened indigenous biodiversity on private land 29 6.5 Protected Areas 30 6.6 Restoration sites 30 6.7 Land Cover Database 31 6.8 Threatened land environments 32 6.9 Ecological Values of Particular Habitat Types 36 7. Analysis of Natural Values 39 7.1 Indigenous Vegetation and threatened Land Environments 39 7.2 Indigenous Vegetation and Threatened Land Environments within Ecological Districts 40 7.3 High Value Indigenous Vegetation in each Ecological District 42 7.4 High Value Indigenous Vegetation within Sub- Catchments 44 7.5 Natural Values that warrant additional protection 48 7.6 The need for additional corridors 49 8. Recreation Values 56 9. Ecosystem Services 57 9.1 Context 57 9.2 What are ecosystem services? 58 9.3 How to value ecosystem services? 61 9.4 Indicative Value of Kaimai-Tauranga Catchment Ecosystem Services 64 9.5 The value of water 67 10. Importance of DOC-managed land 70 5 11. Ecological Effects of Land use Intensification 7271 11.1 SmartGrowth Predicted growth areas and the environment 73272 11.1.1 Areas identified for growth 7372 11.1.2 Areas not identified for Residential Growth 73272 11.2 Opportunities for prevention and mitigation of potential adverse effects 78777 11.2.1 Incentives to Maintain Ecosystem Services 79 11.2.2 Inter-agency and Community Support 81 11.2.3 Standards of Care 82 12. Conclusions 84 13. Acknowledgements 86 14. References 87 15. Appendices 96 15.1 Environmental and Biodiversity Policy in the SmartGrowth Strategy 96493 15.2 Originally Rare Ecosystems 96595 15.3 Land Cover Units within Threatened Land Environments within the Kaimai-Tauranga Catchment 99696 15.4 Indigenous vegetation, within each sub-catchment, that occurs in Acutely and Chronically Threatened land environments within the Kaimai-Tauranga catchment 10097 15.5 Unprotected high value indigenous vegetation/habitats 99 15.6 Stakeholder roles and responsibilities 100 6 LIST OF FIGURES Figure 1: Kaimai-Tauranga study areas showing water catchments and ecological districts. ..............................................................14 Figure 2: SmartGrowth Strategy: Urban Areas and Business Land ....... 17-18 Figure 3: Areas identified as being ecologically significant in the SmartGrowth subregion, western Bay of Plenty..................22 Figure 4: Ecological corridors and outstanding natural features and landscapes within the study area..........................................26 Figure 5: High value indigenous ecological features in the Kaimai-Tauranga catchment. ............................................................................33 Figure 6: Protected natural areas and restoration sites within the Kaimai- Tauranga catchment.............................................................34