ECOLOGICAL ASSESSMENT OF A PROPOSED STRUCTURE PLAN FOR 790C HOT WATER BEACH ROAD, WHENUAKITE R4800 ECOLOGICAL ASSESSMENT OF A PROPOSED STRUCTURE PLAN FOR 790C HOT WATER BEACH ROAD, HOT WATER BEACH View of kānuka forest and scrub in the main gully. Contract Report No. 4800 April 2019 Project Team: Nick Goldwater - Field survey, report author GIS - Federico Mazzieri Tim Martin - Peer review Prepared for: Hot Water Beach (NZ) Ltd 10a Domain Drive Parnell Auckland 1052 © 2019 Contract Report No. 4800 © 2019 Contract Report No. 4800 CONTENTS 1. INTRODUCTION 6 2. METHODS 7 3. ECOLOGICAL CONTEXT 7 3.1 Overview 7 3.2 Climate 7 3.3 Geology and soils 7 3.4 Vegetation 8 3.5 Fauna 9 3.6 Protected areas 9 3.7 Local context 10 3.7.1 Overview 10 3.7.2 Topography 10 3.7.3 Soils 10 3.7.4 Threatened Environment Classification 10 4. VEGETATION AND HABITAT TYPES 11 4.1 Overview 11 4.2 Terrestrial habitats 11 4.3 Freshwater habitats 19 4.3.1 Overview 19 4.3.2 Taiwawe Stream 20 4.3.3 Tributary 1 20 4.3.4 Tributary 2 21 4.3.5 Pond 22 5. FLORA 23 6. FAUNA 23 6.1 Avifauna 23 6.2 Aquatic fauna 23 6.3 Reptiles 24 6.4 Long-tailed bats 24 7. ECOLOGICAL VALUES 24 7.1 Terrestrial values 24 7.2 Aquatic values 25 8. ECOLOGICAL SIGNIFICANCE ASSESSMENT 25 9. THREATS TO ECOLOGICAL VALUES 27 9.1 Stock 27 9.2 Pest animals 27 9.3 Pest plants 28 9.4 Barriers to fish migration 28 © 2019 Contract Report No. 4800 10. POTENTIAL ECOLOGICAL EFFECTS OF THE PROPOSED DEVELOPMENT 29 10.1 Overview 29 10.2 Sedimentation of aquatic and marine habitats 30 10.3 Stormwater and wastewater 30 10.3.1 Stormwater 30 10.3.2 Wastewater 31 10.4 Predation of indigenous fauna by domestic pets 31 10.5 Bird mortality or injury from window strike 31 10.6 Introduction of pest plant species 32 10.7 Removal of stock 32 11. OPPORTUNITIES TO AVOID, MINIMISE OR MITIGATE POTENTIAL ECOLOGICAL EFFECTS 33 11.1 Stormwater 33 11.2 Riparian and terrestrial setbacks 33 11.3 Management of cultivated pest plants 33 11.4 Management of domestic pets 33 11.5 Reducing likelihood of bird window strike 34 12. OPTIONS FOR ECOLOGICAL ENHANCEMENT 34 12.1 Overview 34 12.2 Riparian planting 34 12.3 Revegetation and enrichment planting 34 12.4 Pest plant control 35 12.5 Pest animal control 35 12.6 Remediating barriers to fish migration 35 12.7 Legal protection of natural areas 35 13. SUMMARY AND CONCLUSIONS 35 ACKNOWLEDGMENTS 37 REFERENCES 37 APPENDICS 1. Vascular plant species AT 790c hot water beach road, whenuakite 40 2. Fauna species recorded at 790c hot water beach, whenuakite 44 3. Site concept plan 45 © 2019 Contract Report No. 4800 Reviewed and approved for release by: _________________________ Tim Martin Principal Ecologist Wildland Consultants Ltd Wildland Consultants Ltd 2019 This report has been produced by Wildland Consultants Ltd for Hot Water Beach (NZ) Ltd. All copyright in this report is the property of Wildland Consultants Ltd and any unauthorised publication, reproduction, or adaptation of this report is a breach of that copyright. © 2019 Contract Report No. 4800 1. INTRODUCTION John McDermott and Jeremy Coates (the Clients) are seeking a Plan Change or Variation to introduce a Structure Plan to incorporate a conservation strategy and development proposal for land at Hot Water Beach at 790c Hot Water Beach Road, Whenuakite. A Plan Change/Variation is considered a more appropriate process than making application for a non-complying activity resource consent within the Rural Zone (outside of the coastal environment) under the Proposed Thames-Coromandel District Plan1. This ecological assessment is one of a suite of detailed assessments of the site. It includes an ecological survey and options for ecological restoration and enhancement. To this end, the Clients have commissioned Wildland Consultants Ltd to undertake an ecological assessment and provide an ecological framework for the proposed development. The assessment incorporates the Taiwawe Stream running along its western boundary, together with two interior tributary gully systems and wetland habitats within both northern and western boundaries. This assessment underpins and recommends the conservation framework to support a Structure Plan providing for a maximum of 45 lots within identified Development Areas. A comprehensive Ecological Management Plan (EMP) is recommended to be prepared and submitted at the time of application for subdivision consent to set out the detail of revegetation and enrichment planting, replacement planting where weeds are removed, and buffer planting. The EMP will also cover mitigation measures to ensure restoration and protection of the site’s ecological values, including timeframes required to achieve the ecological outcomes and mitigation measures identified in the ecological assessment. The EMP will be prepared having regard to the subdivision scheme plan being submitted at the time, acknowledging that the scheme plan prepared by Dunwoodie & Green Surveyors Ltd represents a notional subdivision indicative of a possible design and layout. It has been provided and referred to for the purpose of assisting our assessment of the Structure Plan proposal. This ecological assessment supports the setting aside of the Conservation Area identified in the Structure Plan to provide the conservation framework for ecological values and enhancement of biodiversity. Specifically, this report provides the following: Survey methods Ecological context of the study site Description and map of the vegetation and habitat types Description of fauna recorded or likely to be present Terrestrial and ecological values of the site Potential ecological effects for the proposed development Opportunities to avoid or minimise identified effects Options for ecological enhancement 1 A Proposed Hot Water Beach Structure Plan has been prepared for the site by Graeme Lawrence (Planner) Lawrence Cross Chapman & Co Ltd © 2019 6 Contract Report No. 4800 2. METHODS A literature search was undertaken to identify relevant ecological information on the site, and existing information was collated and reviewed. A search of the New Zealand Freshwater Fish Database (NIWA 2018) was undertaken to obtain local records of fish. Field surveys were carried out on 3-4 October 2018 during fine weather, and included a night time spotlighting survey for indigenous fish. Key vegetation and habitat types, including permanent streams and wetlands, were identified, described, and mapped (Figure 1). All vascular plant species observed at the site were recorded (Appendix 1) together with incidental observations of fauna species (Appendix 2). Representative photographs were taken in the field, and these are provided throughout the report. 3. ECOLOGICAL CONTEXT 3.1 Overview The study site is located within the Tairua Ecological District, on the east coast of the Coromandel Peninsula. The following description of Tairua Ecological District is derived from McEwen (1987): Tairua Ecological District is relatively large, and extends from Whitianga to Whangamata on the east coast, and across to the western side of the Coromandel Range, between Thames and Paeroa. Tairua Ecological District is characterised by steep hill country, smaller areas of alluvial plains, and several large river estuaries, including Whitianga Harbour, Whangamata Harbour, the Otahu Estuary, Wharekawa Harbour, and Tairua Estuary. Tairua is one of the most modified ecological districts within the mainland Coromandel Ecological Region and at 89,000 hectares it is also the largest. Much of the lowland and coastal areas are now covered in farmland, exotic forest and scrub as a result of extensive kauri (Agathis australis) logging and repetitive burning. However, the sub-montane zones and steep rugged areas of the lowland zone along the spine of the main range are still forested, although these areas are highly modified by logging. Most of this forested terrain lies within the Coromandel Forest Park. 3.2 Climate Overall, Tairua Ecological District is warm and dry in the summer months and mild in the winter. Annual lowland temperatures range between -2.0 and 28.5º Celsius. Rainfall occurs year round, with mean monthly rainfall between 95 and 210 millimetres. Flooding occurs most commonly in autumn and rainfall is higher in winter. Fog is rare in lowland areas, but occurs more frequently in the ranges. 3.3 Geology and soils © 2019 7 Contract Report No. 4800 In the area surrounding the site, the parent rock is mainly sheets of ignimbrite or rhyolite breccia (Whitianga Group) with extensive intrusions of dome-like rhyolitic lava flows (Minden Rhyolites). Generally, the terrain is less broken and not as steep as in the remainder of Tairua Ecological District. Soils are yellow-brown earths of hill (on ignimbrite flows) and steep land (on rhyolite domes) country. A deep mantle of volcanic ash has been preserved on the large areas of easy terrain resulting in significantly different soils from those on the Thames side. The main soils on the steep and very steep country are Tangatara steep land soils of low fertility. On the rolling to hilly country, mainly in the east and north of Tairua Ecological District, the soils are varied. The main soils are Puketui hill soils (low fertility), Whangamata sandy loam (medium to low fertility), Pukenamu clay loam (low fertility) and Whitianga silt loam (medium fertility). Recent soils from alluvium (Ohinemuri loamy sand to clay loam) are of high fertility and occur mainly around Whitianga Harbour and along the Waiwawa, Whenuakite and Tairua Rivers. Organic soils of Ruakaka peaty loam (low to very low fertility) are relatively more extensive in Tairua Ecological District than elsewhere in the mainland part of Coromandel Ecological Region. 3.4 Vegetation Historical accounts of the vegetation of Tairua Ecological District prior to large- scale modifications carried out by Europeans are extremely limited.