Environmental Pest Plants

DRAFT ECOLOGICAL ASSESSMENT OF PROPOSED REMEDIATION WORKS AT DEANS HEAD AND SHAG ROCK RESERVE, SUMNER-REDCLIFFS ROAD CORRIDOR, CHRISTCHURCH

R3597b

ECOLOGICAL ASSESSMENT OF PROPOSED REMEDIATION WORKS AT DEANS HEAD AND SHAG ROCK RESERVE, SUMNER-REDCLIFFS ROAD CORRIDOR, CHRISTCHURCH

Contract Report No. 3597b

November 2015

Project Team: Melissa Hutchison - Field survey (vegetation), report author Brian Patrick - Field survey (invertebrates), report author Marieke Lettink (Fauna Finders) - Field survey (lizards), report author

Prepared for: Capital Programme Group Christchurch City Council 53 Hereford Street Christchurch 8011

CHRISTCHURCH OFFICE: LEVEL 1, UNIT B, 238 BARRINGTON STREET, P.O. BOX 33-499, BARRINGTON, CHRISTCHURCH 8244; Ph 03-332-3868; Fax 03-332-3869

HEAD OFFICE: 99 SALA STREET, P.O. BOX 7137, TE NGAE, ROTORUA Ph 07-343-9017; Fax 07-343-9018, email [email protected], www.wildlands.co.nz

CONTENTS

1. INTRODUCTION 1

2. ECOLOGICAL CONTEXT 1 2.1 Location 1 2.2 Geology, soils, and climate 2 2.3 Vegetation 3 2.4 Lizards 4 2.5 Invertebrates 4

3. SURVEY METHODS 5 3.1 Vegetation 5 3.2 Lizards 5 3.3 Invertebrates 6

4. DEANS HEAD 6 4.1 Proposed works 6 4.2 Vegetation 7 4.2.1 Indigenous species 7 4.2.2 Introduced species 8 4.3 Fauna 9 4.3.1 Lizards 9 4.3.2 Invertebrates 10 4.4 Ecological significance assessment 11 4.5 Potential effects 13 4.5.1 Vegetation 13 4.5.2 Lizards 13 4.5.3 Invertebrates 13 4.6 Measures to avoid, remedy and/or mitigate potential adverse effects 13 4.6.1 Vegetation 13 4.6.2 Lizards 13 4.6.3 Invertebrates 14 4.7 Conclusions 14

5. SHAG ROCK RESERVE 15 5.1 Proposed works 15 5.2 Vegetation 18 5.2.1 Indigenous vegetation 18 5.2.3 Introduced vegetation 19 5.3 Fauna 19 5.3.1 Lizards 19 5.3.2 Invertebrates 20 5.4 Ecological significance assessment 21 5.5 Potential effects 23 5.5.1 Vegetation 23 5.5.2 Lizards 23 5.5.3 Invertebrates 23 5.6 Measures to avoid, remedy and/or mitigate potential adverse effects 24 5.6.1 Vegetation 24

5.6.2 Lizards 24 5.6.3 Invertebrates 24 5.7 Conclusions 24

6. MEASURES TO ADDRESS POTENTIAL ADVERSE EFFECTS 26

ACKNOWLEDGEMENTS 27

REFERENCES 27

APPENDICES 1. Indigenous vascular plant species list 29 2. Introduced vascular plant species list 30 3. Invertebrate species list 32

Reviewed and approved for release by:

______W.B. Shaw Director/Principal Ecologist Wildland Consultants Ltd

 Wildland Consultants Ltd 2015

This report has been produced by Wildland Consultants Ltd for Christchurch City Council. 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.

1. INTRODUCTION

The road corridor from Lyttelton through to the Sumner Causeway was badly affected by rockfall and cliff collapse hazards as a result of the 2010-2011 earthquakes. As an interim measure, Christchurch City Council (CCC) has placed ballasted shipping containers along the route to prevent rockfall and cliff collapse debris from reaching the road. Most of the route is open to traffic, but the Lyttelton to Evans Pass (Sumner Road) section remains closed under a Canterbury Earthquake Recovery Authority (CERA) Section 46 closure.

Christchurch City Council proposes to undertake remediation works along the Sumner-Lyttelton road corridor to mitigate the current levels of risk. The approach proposed is to eliminate major risk by source rock deconstruction (scaling, blasting, and benching) and to isolate risk by containing rockfall (construction of bunds, mesh drapes, and shotcrete). Proposed remediation works will occur in four main areas (see Figure 1):

 Sumner Road, Lyttelton;  Wakefield Avenue, Sumner;  Clifton Hill, Clifton (eastern end of Peacocks Gallop);  Shag Rock Reserve (middle of Peacocks Gallop)  Deans Head, Clifton (western end of Peacocks Gallop);  Moa Bone Point, Redcliffs.

Remediation measures proposed for the Sumner Road section have already been assessed in a previous ecological report (Davis et al. 2014).

Christchurch City Council commissioned Wildlands Consultants Ltd, in collaboration with Fauna Finders, to carry out an ecological survey and assessment of the effects of the proposed remediation works along the Sumner to Redcliffs section of the road corridor, i.e. the five sites from Wakefield Avenue to Moa Bone Point. This report covers two of the remediation sites – Deans Head and Shag Rock Reserve. The other three sites (Wakefield Avenue, Clifton Hill, and Moa Bone Point) are assessed in a separate report (Wildland Consultants 2015). Both reports contain a description of the ecological features and values – vegetation, lizards, and invertebrates only – at each site, an assessment of the potential effects of the proposed works on those values, and suggested measures to avoid, remedy, and/or mitigate any potential adverse effects.

2. ECOLOGICAL CONTEXT

2.1 Location

The four remediation sites are located along the road corridor between Sumner and Redcliffs in southeast Christchurch (Figure 1). The sites are situated in the Port Hills Ecological District (ED), which is part of the Banks Ecological Region. The Port Hills ED is bounded by Lyttelton Harbour to the south and east, the Canterbury Plains to the north and west, and the Herbert Ecological District to the south (Wilson 2013).

Figure 1: Location of the proposed remediation works: Section 1 - Sumner Road (not covered in this report as it was assessed in Davis et al. 2014). Section 2 - Wakefield Avenue, Section 3 - Peacocks Gallop (i.e. Clifton Hill, Shag Rock Reserve, and Deans Head sites), and Section 4 - Moa Bone Point. Map supplied by Christchurch City Council, November 2014.

2.2 Geology, soils, and climate

Rocks of the Port Hills Ecological District consist of basaltic flows and pyroclastics from Miocene Lyttelton volcanics, with a fringe of deep Pleistocene loess of generally coarse texture (McEwen 1987). The topography of the Ecological District consists of hills, which rise steeply from sea level at Lyttelton Harbour, and less steeply from the northern and western margins, to a maximum altitude of 573 m a.s.l. Although most of the hill tops are rounded, prominent tors, bluffs and rock outcrops are common along the ridges.

Soils on the lower slopes consist of loess with pale-coloured compact subsoils - yellow-grey earths - which are drought-prone in summer (McEwen 1987). On higher slopes with higher rainfall, soils are derived from basalt or loess or mixtures of these; those from basalt have dark brown, blocky-structured, stony clay loam subsoils, while those from loess have yellowish-brown, friable to firm, silty subsoils. Those from mixed loess/basalt have intermediate features. There are also some small areas of recent alluvium at the mouths of some valleys. These include gley recent soils, saline gley recent soils, yellow-brown sand, and organic soils (peaty loams).

The climate is characterised by warm summers and cool winters, with frequent frosts and occasional light snowfalls (McEwen 1987). Rainfall averages 600-700 mm p.a., and is more or less evenly spaced throughout the year, but occasional summer droughts can be harsh enough to cause severe wilting and some mortality of trees in indigenous forest (Wilson 2013). Rainfall increases with altitude and along a north- eastern to south-western gradient. Prevailing winds are easterly, but occasional strong, dry north-west winds can exacerbate summer drought conditions.

2.3 Vegetation

The original vegetation cover of the Port Hills Ecological District consisted almost entirely of podocarp-hardwood forest, with small pockets of subalpine shrubland and grassland on the most exposed ridges (Wilson 1992, 2013). The main forest canopy species were lowland tōtara (Podocarpus totara), mataī (Prumnopitys taxifolia), kahikatea (Dacrycarpus dacrydioides), māhoe (Melicytus ramiflorus), broadleaf (Griselinia littoralis), kaikomako (Pennantia corymbosa) and pigeonwood (Hedycarya arborea). Montane forest with thin-bark tōtara (Podocarpus cunninghamii), broadleaf, horopito (Pseudowintera colorata) and soft-leaved tree fern (Cyathea smithii) was present above about 500 m. On the highest bluffs were non- forest montane species, including snow tussock (Chionochloa rigida) and inaka (Dracophyllum acerosum). Rock outcrops provided habitat for a suite of specialist plant species, including the Banks Peninsula sun hebe (Heliohebe lavaudiana), blanket fern (Pleurosurus rutifolius), Banks Peninsula button daisy (Leptinella minor), and Lyttelton forget-me-not (Myosotis lytteltonensis). Many of these species are endemic to Banks Peninsula and are nationally Threatened or At Risk (see de Lange et al. 2013).

The original forest cover on the Port Hills (and the rest of Banks Peninsula) was almost completely removed by successive waves of Māori and European colonisation (as a result of logging, burning, and farming). By 1900, forest destruction was virtually complete, and only small fragments of indigenous forest remained, mainly in the southern end of the Port Hills (Wilson 1992). Since then, there has been a gradual increase in the extent of woody vegetation across Banks Peninsula; secondary growth kānuka (Kunzea robusta) forest, mixed podocarp-hardwood forest, and small-leaved shrubland now cover c.15% of the land area. Although vegetation on the Port Hills is now mostly exotic-dominant grassland, there are substantial areas of secondary- growth hardwood and kānuka forest. Rock outcrops continue to support a number of specialist plant species, although weed invasion increasingly threatens these habitats (Wilson 2013).

2.4 Lizards

The Port Hills Ecological District supports five species of native lizard, four of which are of conservation concern (Table 1; Lettink & Whitaker 2004, Department of Conservation Herpetofauna Database). The Ecological District contains a range of habitats for lizards including grasslands, shrublands, forests and rocklands (rock outcrops, bluffs and boulder fields). Habitat mosaics are common, e.g. grassland- rockland-shrubland mosaics. Vegetation present in these habitats may be indigenous, introduced, or a mixture of both.

Table 1: Lizard species found in the Port Hills Ecological District and their conservation status (from Hitchmough et al. 2013).

Common Name Scientific Name Conservation Status Central Canterbury Oligosoma aff. lineoocellatum Threatened-Nationally spotted skink ‘central Canterbury’ Vulnerable Jewelled gecko Naultinus gemmeus At Risk-Declining Common skink clade 5 Oligosoma aff. polychroma Clade 5 At Risk-Declining Canterbury gecko Woodworthia cf. brunnea At Risk-Declining McCann's skink Oligosoma maccanni Not Threatened

Lizard distribution in urban Christchurch is patchy and species richness is low (typically one or occasionally two species; Department of Conservation Herpetofauna Database). The most frequently encountered species is common skink clade 5 (Oligosoma aff. polychroma Clade 5; hereafter ‘common skink’). This undescribed member of the common skink cryptic species complex (Liggins et al. 2008) remains relatively abundant in the eastern hill suburbs (ML, pers. obs.). Canterbury gecko (Woodworthia cf. brunnea) may persist at Port Hills sites which retain or adjoin fissured bluffs and rock outcrops (its main refuge habitat). McCann’s skink (Oligosoma maccanni) may co-exist with common skink, but is rarely reported from urban areas (Department of Conservation Herpetofauna Database). Important refuge habitats for lizards in urban Christchurch include rank grassland, rock walls, railway embankments, relatively unkempt gardens, reserves, and parklands.

2.5 Invertebrates

The proposed remediation sites along the Sumner-Redcliffs road corridor generally comprise high rock bluffs with varying amounts of forest and grassland at the base of the cliffs. Natural rock faces on Banks Peninsula, including the Port Hills, would have once supported a distinctive and important indigenous moth fauna. This would have included 15 species of indigenous moths in seven families that live exclusively on rock faces, and depend on a covering of herbs, lichens, mosses, and algae for their larval foodplants. Of these, the oenochromine day-flying moth Dichromodes cynica and choreutid moth Asterivora new species are endemic to Banks Peninsula, while Gadira petraula has a restricted distribution in the northeast South Island and has perhaps its largest population on Banks Peninsula. This species has a flightless female that makes the species effectively immobile and it is classified as At Risk-Naturally Uncommon by the Department of Conservation (Hitchmough et al. in press).

3. SURVEY METHODS

3.1 Vegetation

A brief reconnaissance visit to the Deans Head site was undertaken on 26 January 2015, in order to familiarise the authors with the scope of the engineering works proposed. A survey of the vegetation at the site was then carried out on 25 March 2015. At the time of the field survey, CERA was still demolishing houses within the area proposed for benching at Deans Head (see Figure 4). Most of the Deans Head site was not able to be surveyed due to safety reasons, and much of the existing vegetation is likely to be removed as part of the demolition works (this work is already consented). A brief inspection on foot was made of the southern end of the property at 286 Main Road, however no attempt was made to document all of the garden plants. Rock faces below 286 Main Road were viewed briefly through the fences (the area behind the shipping containers was not entered).

A brief survey of the vegetation at Shag Rock Reserve was carried out on 15 October 2015. The vegetation was surveyed from the roadside with binoculars, as access was not possible behind the shipping containers due to the rockfall hazard.

During each survey visit, a list of indigenous vascular plant species was compiled, which included whether they appeared to be planted or wild, i.e. self-sown. Indigenous species were then divided into those that occur naturally in the Port Hills Ecological District (according to Wilson 1992) and those which are native to other parts of New Zealand (i.e. they do not occur naturally in the Port Hills Ecological District). An introduced vascular plant species list was also compiled; focussing on species listed as invasive pests and on naturalised species with potential to spread in the area. This assessment was based on the species listed in the Canterbury Regional Pest Management Strategy (Maw 2011), Christchurch City Council Operational Pest Management Plan (2010), Howell (2008), Schmechel (2009), and Wilson (1999), as well as the author’s (MH) knowledge of invasive weeds.

No existing literature or other relevant information on vegetation is known for these remediation sites.

3.2 Lizards

Local knowledge, relevant information, such as Department of Conservation Herpetofauna Database records, a brief site visit to Deans Head and roadside inspection of Shag Rock Reserve were used to infer potential species’ presence. Based on the above information, lizard species that may be present in the affected areas, in order of likelihood, are common skink, Canterbury gecko and McCann’s skink. The Deans Head visit on 19 February 2015 was necessarily brief due to safety restrictions, and as such, was insufficient to determine abundance and distribution.

3.3 Invertebrates

A field survey of the invertebrates at the Deans Head site was carried out on 25 March 2015. The survey took place in suitable warm and calm weather conditions. The following survey methods were used, bearing in mind the limitations of a brief daytime survey, undertaken in mid autumn (i.e. at the end of the season when invertebrates are most active):

 Sweep-netting of vegetation.  Hand-netting of flying species.  Observations of day-active species or resting species.  Observations of characteristic larval feeding damage on the flora.

Most of the invertebrate species found were identified in the field and released, but some more interesting specimens were kept as vouchers and are stored dry in the private collection of the author (B. Patrick).

Shag Rock Reserve was not able to be directly surveyed for invertebrates, as access to the site was not possible on foot (due to safety reasons). However, an assessment of invertebrates likely to be present at the site was able to be made, using knowledge of invertebrate species known from adjacent areas and habitat profiling i.e. the vegetation and habitats present at the site (this was determined from photographs taken during the vegetation survey on 15 October 2015 and from drone footage supplied by CCC).

No previous documented invertebrate surveys are known for these sites.

4. DEANS HEAD

4.1 Proposed works

The remediation works proposed at Deans Head (see Figure 2) are described in detail in Aurecon (2014c). A brief summary of the works is set out below:

 Removal of loess-colluvium overburden and deconstruction of source rock hazard (including removal of human-made rock retaining walls) by excavation to form benches (170,000 m3 spoil).

 Roading assets - no reconstruction required.

 Shipping containers will be removed once the works are completed, but fencing is expected to be erected to control public access to the CERA Section 45 hazard zone at Shag Rock Reserve.

 Estimated construction time is 66 weeks.

Figure 2: Location of proposed remediation works at Deans Head, Clifton. Source: Aurecon (2014c).

4.2 Vegetation

4.2.1 Indigenous species

Most of the Deans Head site is located within a residential area, which would have been developed well over one hundred years ago. The site includes a number of suburban gardens, as well as steep banks, cliffs, and rock faces (Plates 1-6). The original vegetation at the site has been removed completely, even from relatively inaccessible areas such as cliff faces. Vegetation on the cliffs has been further disturbed recently by rock fall and scaling works.

Only a small number of indigenous plant species were observed growing wild at the site, such as cabbage tree (Cordyline australis), ngaio (Myoporum laetum), and large- leaved pōhuehue (Muehlenbeckia australis) (see Appendix 1 for a list of indigenous plant species recorded at the site). A wide variety of indigenous species have been planted the site, however most of these do not occur naturally within the Port Hills Ecological District (cf. Wilson 1992). For example, puka (Meryta sinclairii), karo (Pittosporum crassifolium), and various Hebe species (including cultivars) were seen in the gardens at 284-286 Main Road. Wild seedlings of karo and taupata (Coprosma repens), both well south of their natural range, were also observed at the site.

None of the indigenous vascular rock outcrop flora remains, although several indigenous non-vascular plant species were observed on the human-made rock walls at 286 Main Road. This includes several species of lichen (Plate 7) and at least one species of moss (Syntrichia antarctica) (Plate 8).

Plate 1: Weed-infested vegetation on a steep Plate 2: Gardens at Deans Head contain a huge section at the bottom of 284 Main Road. variety of indigenous and introduced plant species (stair access for 284-286 Main Road).

4.2.2 Introduced species

A diverse variety of introduced plant species, both planted and wild, is present at the site, and only a small selection of the species were recorded during the site visit (see Appendix 1 for a list of introduced plant species recorded at the site). Some of these species pose a major threat to indigenous biodiversity and are listed in the Canterbury Regional Pest Management Strategy (Maw 2011). For example, old man’s beard, (Clematis vitalba), sycamore (Acer pseudoplatanus), boneseed (Chrysanthemoides monilifera), and Cotoneaster franchetii.

Rock face vegetation is dominated by introduced weeds and garden escapes such as boneseed, spur valerian (Centranthus ruber), pigs ear (Cotyledon orbiculata), pinwheel aeonium (Aeonium haworthii), boxthorn (Lycium ferocissimum), and pale dew plant (Drosanthemum floribundum) (Plates 3-6).

Plate 3: Weed-infested rock faces at Deans Head Plate 4: Highly modified rock-faces at Deans Head (below 284 Main Road). (taken from the stairs below 284 Main Road).

Plate 5: Natural but highly modified rock faces Plate 6: Human-made rock retaining walls above behind the shipping containers at Deans Head natural rock faces at Deans Head (286 Main (below 286 Main Road). Road).

Plate 7: Several species of indigenous lichens (not Plate 8: Indigenous mosses, such as Syntrichia identified) were present on human-made rock Antarctica shown here, were relatively common on walls at 286 Main Road, Deans Head. human-made rock walls at 286 Main Road, Deans Head.

4.3 Fauna

4.3.1 Lizards

A 20-minute search was undertaken along the footpath below 286 Main Road and up the stairs to the stone house at this address (see Plate 2). Surface debris (rocks and various human-made materials) were overturned, and crevices in rock faces and walls were inspected using a torch. One common skink (Oligosoma aff. polychroma Clade 5) was found under a piece of wood at 286 Main Road (Plate 9). Searching was abandoned after this find. The rock walls and face below did not appear to have any suitable crevices for Canterbury gecko (Woodworthia cf. brunnea), but its presence cannot be ruled out because only a small area was searched and apparently-suitable habitat remains in the vicinity (creviced bluffs to the east). Canterbury gecko may persist in rock walls and/or inhabit houses remaining in this area, particularly those built a long time ago.

Plate 9. Common skink (Oligosoma aff. polychroma Plate 10. There are large areas of man- Clade 5) caught at Deans Head. made rock walls at 286 Main Road, Deans Head.

4.3.2 Invertebrates

At the Deans Head site there are extensive areas of man-made rock walls towering above Main Road (Plates 6 and 10). On these walls, three endemic moth species were found breeding on the extensive cover of indigenous lichens and mosses. These species are:

 The specialist rock face moth Gadira petraula (Crambidae) (Plates 11-12). This is a nationally rare species, classified as At Risk-Naturally Uncommon by the Department of Conservation in their latest threat ranking (Hitchmough et al. in press). Even though Banks Peninsula is its national stronghold, it is known from just six sites there. The species has a flightless female (Plate 11), limiting its dispersal ability, and therefore its ability to colonise new habitat. Larvae feed under a layer of silk, on lichens growing on rock faces (Plate 12). In my experience the Deans Head site appears to contain a relatively large population of this moth.  Kiwaia brontophora (Gelechiidae). A specialist moth species of rock faces. Larvae of this tiny speckled moth are feeding in silk tunnels within mosses (e.g. Syntrichia antarctica) on the rock faces (Plate 8).  The geometrid moth Helastia cinerearia (Geometridae). Its looper larvae feed on mosses growing on rock faces (e.g. Plate 8). This is a widespread moth species in rocky habitats.

All three moth species are distributed across Banks Peninsula on the most natural rock faces. They have adapted to living on the human-made rock walls at Deans Head because of their close resemblance to natural rock faces. Important characteristics are the walls’ age, lack of disturbance, and the presence of indigenous (non-vascular) plants. When these rock walls were built, natural rock faces and their associated indigenous plants and insect fauna must have been present adjacent to the rock walls being built. This enabled even flightless insect species to walk onto the newly constructed rock walls once a natural lichen and moss flora had established. Other indigenous insects, including beetles, could also be present in these habitats (see Appendix 2 for a list of invertebrate species recorded at the site).

Plate 11: Short-winged, flightless female of the Plate 12: Characteristic larval webbing of indigenous specialist rock face moth Gadira Gadira petraula on a rock face, where the petraula (At Risk-Naturally Uncommon). larvae feed on lichens.

4.4 Ecological significance assessment

Ecological significance of the remediation Deans Head site was assessed using the 10 criteria in Appendix 3 of the Canterbury Regional Policy Statement (see Table 2). Separate comments are provided for vegetation, lizards, and invertebrates for each criterion (where relevant). Interpretation of the criteria was based on the guidelines in Wildland Consultants (2013). A site is considered to be significant if it meets one or more of the criteria. Based on this assessment, the Deans Head site is considered to be ecologically significant because it meets at least one of the criteria (for lizards and invertebrates).

Table 2: Ecological significance assessment for the Deans Head site using criteria in Appendix 3 of the Canterbury Regional Policy Statement. Liz = Lizards, Inv = Invertebrates.

Criterion Met Explanation - Deans Head

Representativeness

1. Indigenous vegetation or habitat of Yes  The original vegetation cover has been indigenous fauna that is representative, Liz completely removed, and there are very few typical or characteristic of the natural Inv indigenous plant species at the site. diversity of the relevant ecological district.  Contains habitat for common skink and This can include degraded examples potential habitat for Canterbury gecko where they are some of the best remaining (Woodworthia cf. brunnea) (NB. its presence examples of their type, or represent all that was not confirmed). remains of indigenous biodiversity in some

areas.  Contains characteristic invertebrate fauna: rock face moths. Although most of the rock face habitat is human-made, it is covered in indigenous non-vascular plants and is mimicking natural rock surfaces.

2. Indigenous vegetation or habitat of Yes  The site appears to be extensive and indigenous fauna that is a relatively large Inv important for the indigenous rock moth example of its type within the relevant fauna. ecological district.

Criterion Met Explanation - Deans Head

Rarity/Distinctiveness

3. Indigenous vegetation or habitat of No indigenous fauna that has been reduced to less than 20% of its former extent in the Region, or relevant land environment, ecological district, or freshwater environment.

4. Indigenous vegetation or habitat of Yes  Contains habitat for common skink (At Risk- indigenous fauna that supports an Liz Declining) and potential habitat for indigenous species that is threatened, at Inv Canterbury gecko (At Risk-Declining). risk, or uncommon, nationally or within the  Supports what appears to be a relatively relevant ecological district. large population of the specialised rock face moth Gadira petraula (At Risk-Naturally Uncommon).

5. The site contains indigenous vegetation or ?  Canterbury gecko may be present. It is an indigenous species at its distribution Liz restricted to Canterbury and S Marlborough. limit within Canterbury Region or  No indigenous plant or invertebrate species nationally. at their distribution limits.

6. Indigenous vegetation or an association of Yes  Rock face moth fauna is now of restricted indigenous species that is distinctive, of Inv occurrence and is part of a nationally rare restricted occurrence, occurs within an ecosystem (i.e. basic cliffs, scarps and tors originally rare ecosystem, or has in Williams et al. 2007). developed as a result of an unusual environmental factor or combination of factors.

Diversity and Pattern

7. Indigenous vegetation or habitat of No  The site does not have a high diversity of indigenous fauna that contains a high indigenous species or habitat types. diversity of indigenous ecosystem or habitat types, indigenous taxa, or has changes in species composition reflecting the existence of diverse natural features or ecological gradients.

Ecological Context

8. Vegetation or habitat of indigenous fauna Yes  The site is part of an important network of that provides or contributes to an important Inv rock face habitats for insect fauna across the ecological linkage or network, or provides Port Hills. Introduced weeds spreading over an important buffering function. these rock faces and ongoing suburban developments are truncating the natural linkages between natural rock face sites.

9. A wetland which plays an important No  The site does not contain any wetlands. hydrological, biological or ecological role in the natural functioning of a river or coastal system.

10. Indigenous vegetation or habitat of Yes  Contains breeding and feeding habitats for indigenous fauna that provides important Liz at least one indigenous lizard species habitat (including refuges from predation, Inv (common skink clade 5). or key habitat for feeding, breeding, or  Although human-made, the site is an resting) for indigenous species, either important habitat for indigenous moths. seasonally or permanently.

4.5 Potential effects

4.5.1 Vegetation

The proposed benching will result in the complete removal of vegetation cover from the site. However, there is no significant indigenous vegetation at the site, as the original vegetation cover was destroyed over a century ago and at present the site consists of privately-owned suburban gardens where most of the indigenous species have been planted. A few naturally occurring indigenous species were recorded, but these are common and widespread in the Sumner-Redcliffs area, e.g. cabbage trees and pōhuehue. Overall, effects on indigenous vegetation from the proposed works are therefore likely to be less than minor.

4.5.2 Lizards

Potential adverse effects of the proposed works on lizards include injury and mortality that will be incurred during vegetation clearance and earthworks. The proposed works will also result in the loss of lizard habitat. Demolition and removal of houses and associated structures, which was occurring at Deans Head at the time of the field survey, will result in mortality of common skink clade 5 and potentially of Canterbury gecko. Current and proposed works for Deans Head are likely to have a moderate to major effect on the resident skink population (depending on numbers present). Most, if not all, of the individuals living in the affected area are expected to be lost.

4.5.3 Invertebrates

Human-made rock walls at Deans Head currently provide habitat for both widespread and rare indigenous insects, as the surfaces mimic the habitats provided by natural rock faces. It is not known how widely distributed or abundant these rock face species are at the site or if they are present in similar habitats in the surrounding area. Removal of the rock walls would destroy these habitats and lead to the loss of these specialist invertebrate species from the site, and potentially from the wider Sumner- Redcliffs area (if this is the only site where they occur). The proposed works therefore could have major adverse effects on significant invertebrate values at this site.

4.6 Measures to avoid, remedy and/or mitigate potential adverse effects

4.6.1 Vegetation

No significant botanical values are present at the Deans Head site, therefore it is not necessary to avoid, remedy and/or mitigate any potential adverse effects on vegetation.

4.6.2 Lizards

Remediation measures proposed for lizards are dealt with in a separate Lizard Management Plan (Lettink 2015). Briefly, the following action is recommended:

 Revegetate benched surfaces at Deans Head once house removal and earthworks have been completed. Hydro-seeding (with drought-tolerant introduced grasses)

should provide suitable habitat for common skink clade 5 within a relatively short time-frame (<3 years) and permit colonisation by skinks from adjacent areas (skinks are present on unaffected slopes south/south-west of Deans Head; ML pers. obs.).

4.6.3 Invertebrates

Deans Head may currently provide the best rock face habitats for indigenous insects on the northern side of the Port Hills; paradoxically based not on natural rock faces, but on human-made rock walls formed at a time when natural rock faces were widespread in the area. Presumably because the natural rock walls were both common at this time and adjacent, indigenous moths were able to colonise these new surfaces once lichens, mosses and algae had populated the human-made walls.

In order to conserve the significant indigenous invertebrate fauna at the site it is suggested that the following measures are implemented:

 Prior to commencement of the works, where safe access is possible, rock walls proposed for removal should be inspected by a suitably experienced ecologist (entomologist) to determine the presence of indigenous rock face moths.

 Rock walls should be removed carefully in order to minimise disturbance to surface vegetation/habitats, and placed in Shag Rock Reserve in a vertical position (or close to) with the vegetated side facing outwards. Ideally this work should be carried out in consultation with a suitably experienced ecologist on-site.

 Removal of the rock walls would ideally be carried out in the period March to August, in order to be least disruptive to the life cycle of the moth species. At other times of year adult males will be flying, mating or otherwise dispersing and disturbance to rock faces at this time will greatly disrupt them. The moth Gadira petraula with its flightless female is particularly vulnerable to any disturbance when the immobile females are attracting the flying males.

 Control of invasive weeds present on the rock walls (such as boneseed, spur valerian, and pigs ear) would be desirable, as these weeds shade the rock and displace indigenous mosses and lichens, thus reducing the habitat available for specialist rock face insects.

 No public access to the site is recommended, as this could have an adverse impact on specialist rock outcrop plants and fauna. Site interpretation could, however, be provided in a suitable location nearby.

4.7 Conclusions

Most of the area proposed for benching at Deans Head was not able to be physically visited and surveyed because house demolitions were still in progress at the time of the field survey, therefore this assessment of effects was limited to the area that was able to be surveyed. The Deans Head site contains significant lizard and invertebrate values, which will be adversely affected by the proposed remediation works. Implementation of the mitigation measures set out above will help to avoid, remedy and/or mitigate potential adverse effects on the rare rock face moths.

5. SHAG ROCK RESERVE

5.1 Proposed works

The location and scope of the remediation works proposed at Shag Rock Reserve are shown in Figure 3. A detailed description of the proposed works was not available at the time of writing this report (November 2015), however a brief summary of the works (inferred from Figure 3) is given below:

 Deposition of spoil (44,000 m3) from remediation works at Deans Head.

 Re-contouring of earthquake-induced talus slopes and levelling of the ground surface, followed by benching (106,000 m3). Leaving the boulder fields in their current state is not an option because they provide a ramp that increases rockfall risk to road users.

 Revegetation of the ground surface (at the time of this report the proposed vegetation cover was not known).

 Construction of a bund formed from rocks and talus along the road boundary (7780 m3). The bund will measure 6 m high, 6 m wide at the base and 3 m wide at the top, with a total length of 290 m.

 Erection of a mesh fence along the road boundary with a gate to restrict access to the area.

 No remediation works are proposed for the rock faces?

 Roading assets - no reconstruction required?

 Shipping containers will be removed once the works are completed?

Figure 3: Location of proposed remediation works at Shag Rock Reserve, with Deans Head in the foreground at right and Clifton Hill in the background. Source: Aurecon (map supplied by CCC September 2015).

Figure 4. Aerial views of Shag Rock Reserve, Clifton. A. The top image was taken two days after the 6.3-magnitude earthquake that occurred on 22 February 2011, and shows rockfall debris from the collapse of c. 10–15 m of cliff edge (source: Canterbury Maps, Environment Canterbury). B. The bottom image was taken in August 2015 and shows the ballasted shipping containers, boulder fields, debris from the demolition of cliff-edge houses, and vegetation cover (source: CCC).

5.2 Vegetation

5.2.1 Indigenous vegetation

The original vegetation cover at Shag Rock Reserve was destroyed a long time ago as a result of urban development and the use of the site as a public amenity area. Prior to 2011, the main vegetation cover at the site consisted of introduced grassland (maintained by mowing), with smaller areas of planted trees (both native and introduced species) (see Figure 4A). The site has undergone substantial changes since the earthquakes in 2010-11, with much of the site now being covered in talus and boulderfield as a result of cliff collapse and ongoing rock fall (see Figure 4B).

Some indigenous species were planted at the site prior to 2011, however some of these species are not ‘native’ to the Port Hills Ecological District i.e. they do not occur naturally in the area (cf. Wilson 1992). For example, pōhutukawa (Metrosideros excelsa) and North Island lacebark (probably Hoheria populnea).

Only seven indigenous plant species were observed growing wild at the site during the roadside survey on 15 October 2015: ngaio (Myoporum laetum), akeake (Dodonaea viscosa), cabbage tree (Cordyline australis), poroporo (Solanum laciniatum), large- leaved pōhuehue (Muehlenbeckia australis), Senecio glomeratus, and taupata (Coprosma repens, well south of its natural range) (see Appendix 1 for a list of indigenous plant species recorded at the site). Other indigenous herbaceous species could be present underneath trees and shrubs at the site, however these smaller plants would be difficult to see from the roadside.

None of the indigenous vascular rock outcrop flora appears to remain on the cliffs, however indigenous non-vascular plant species (i.e. mosses and lichens) are likely to present, as they were found nearby at Deans Head in March 2015.

Plate 13: A small number of native trees and shrubs are present at Shag Rock Reserve, including ngaio (Myorporum laetum), akeake (Dodonaea viscosa), and cabbage tree (Cordyline australis).

5.2.3 Introduced vegetation

The area of introduced grassland at Shag Rock Reserve has reduced substantially since 2011, as it has largely been buried under rockfall debris (see Figure 4B), however the abundance and diversity of introduced trees and shrubs at the site appears to have increased dramatically (Plates 14-15). Many of these species will have spread into the site from adjacent private gardens and roadsides.

In total, 31 introduced vascular plant species were observed at Shag Rock Reserve; this includes a number of invasive weeds (see Appendix 2 for a list of introduced plant species recorded at the site). Several introduced species were planted at the site in the past, such as Eucalyptus sp., Aloe arborescens, Aloe sp., and phoenix palm (Phoenix canariensis).

Some of the most common and conspicuous introduced plant species observed at the site were: Pride of Madeira (Echium candicans), boneseed (Chrysanthemoides monilifera, a Containment Control Pest in the Canterbury Regional Pest Management Strategy, Maw 2011), boxthorn (Lycium ferocissimum), purple groundsel (Senecio elegans), marguerite daisy (Argyranthemum frutescens), and tree lupin (Lupinus arboreus). A few plants of old man’s beard (Clematis vitalba) and Scotch broom (Cytisus scoparius), both Containment Control Pests (Maw 2011), were also seen.

Plate 14: A variety of colourful introduced plant Plate 15: Pride of Madeira (Echium candicans) species have invaded Shag Rock Reserve has colonised the boulderfield and is now one of following the earthquakes in 2010-11. the most common species at the site.

5.3 Fauna

5.3.1 Lizards

Shag Rock Reserve was not searched due to access restrictions. This area was a well- maintained park prior to the Canterbury earthquakes, containing lawns and exotic palm specimens. Regularly-maintained areas (e.g. mown lawns) of the Reserve are highly unlikely to have supported lizards at that time. However, Canterbury gecko would almost certainly have occupied suitable crevices on the cliff faces (particularly areas of columnar basalt containing “faults” or joints in the rock that are narrow and deep and of the dimensions preferred by this species for its communal retreat sites). Common skink (and possibly McCann’s skink) may have been present in areas that were not mown and less steep (e.g. rank grass along the base and tops of the cliffs).

The boulder fields and unmaintained (predominantly introduced) vegetation that currently occupy the Reserve constitute better lizard habitat (particularly for skinks) than the manicured parkland present pre-quake. Thus, it is likely that skinks have colonised the area from adjacent hill slopes (e.g. Deans Head) in the intervening period. Canterbury geckos may also have colonised the boulder fields if able to survive the extensive cliff collapse (loss of c. 10-15 m of cliff edge) caused by the earthquakes. If lizards have colonised and established in the Reserve since the quakes, populations are likely to be small due to low reproductive rates, particularly for Canterbury gecko.

5.3.2 Invertebrates

Shag Rock Reserve was not able to be surveyed for invertebrates because of access restrictions, but an assessment of invertebrates likely to be present was made using photographs and drone footage supplied by CCC, and information from the vegetation survey. From examination of the photographs and drone footage there appears to be no natural vegetation or habitats remaining in the base area of Shag Rock Reserve, therefore no significant indigenous invertebrate values are expected to be present, however the cliffs appear to have some remnant natural rock face still present at each end of the site (Plate 13). The indigenous lichen cover of the rock faces is conspicuous in this and other photographs.

Following the major earthquakes in 2010-11 and associated rock fall, the base area has become a jumble of rocks and soil, which has been colonised by a wide range of introduced plant species. This weedy area will be providing habitat for mainly introduced invertebrates such as the Australian leaf-roller moth Epiphyas postvittana.

Several of the indigenous plant species at the site may support indigenous moths, based on my observations from the immediate vicinity of the reserve as follows:

 Muehlenbeckia australis – the noctuid moths Meterana stipata and M. alycone, and the geometrid moths Pseudocoremia indistincta and Pasiphila muscosata may be feeding on the foliage of this widespread liane, while the larvae of the orange moth Morova subfasciata may be living in a swelling on the stems.

 Solanum laciniatum – the pryraustine moth Sceliodes cordalis, whose larvae feed within the poroporo berries, and the tiny gelechiid Symmetrischema plaesiosema boring in its stems.

 Senecio glomeratus – the larvae of the magpie moth Nyctemera annulata will likely be utilising this larval hostplant.

 Cordyline australis – the caterpillars of the cabbage tree moth Epiphyrne verriculata is common on cabbage tree foliage in the area.

All of these indigenous moth species are widespread and common in the Port Hills and wider area.

5.4 Ecological significance assessment

Ecological significance of the Shag Rock Reserve remediation site was assessed using the 10 criteria in Appendix 3 of the Canterbury Regional Policy Statement (Table 3). Separate comments are provided for vegetation, lizards, and invertebrates for each criterion (where relevant). Interpretation of the criteria was based on the guidelines in Wildland Consultants (2013). A site is considered to be significant if it meets one or more of the criteria. Based on this assessment, Shag Rock Reserve is considered to be ecologically significant because it meets at least one of the criteria (for invertebrates) and is potentially significant for lizards.

Table 3: Ecological significance assessment for the Shag Rock Reserve remediation site using criteria in Appendix 3 of the Canterbury Regional Policy Statement. Liz = Lizards, Inv = Invertebrates.

Criterion Met Explanation – Shag Rock Reserve

Representativeness

1. Indigenous vegetation or habitat of Yes?  The original vegetation cover has been indigenous fauna that is representative, Liz completely removed, and there are very typical or characteristic of the natural Inv few indigenous plant species at the site. diversity of the relevant ecological district.  Contains potential habitat for common This can include degraded examples skink clade 5 and Canterbury gecko where they are some of the best remaining (Woodworthia cf. brunnea) (NB. their examples of their type, or represent all that presence could not be confirmed). remains of indigenous biodiversity in some areas.  Based on detailed examination of recent photographs, the site is highly likely to contain characteristic rock face moth fauna on remnant natural rock surface (NB. their presence could not be confirmed).

2. Indigenous vegetation or habitat of Yes  Prior to the Canterbury earthquakes, the indigenous fauna that is a relatively large Liz site provided a relatively large area of example of its type within the relevant cliff habitat for Canterbury gecko. Much ecological district. of this (c. 10-15 m of cliff edge) has since been lost, leaving only small pockets of potential habitat remaining for this species.  From recent photographs and drone footage it appears quite large areas of remnant natural rock surface have survived. These are highly likely to contain significant populations of several indigenous moth species, one of which is a threatened species.

Rarity/Distinctiveness

3. Indigenous vegetation or habitat of No  The site does not contain indigenous indigenous fauna that has been reduced to vegetation or habitats of indigenous less than 20% of its former extent in the lizards or invertebrates that meet this Region, or relevant land environment, criterion. ecological district, or freshwater environment.

Criterion Met Explanation – Shag Rock Reserve

4. Indigenous vegetation or habitat of Yes  Contains potential habitat for common indigenous fauna that supports an Liz skink clade 5 and Canterbury gecko indigenous species that is threatened, at Inv (both At Risk-Declining). risk, or uncommon, nationally or within the  Likely to support a population of the moth relevant ecological district. Gadira petraula (At Risk-Naturally Uncommon).

5. The site contains indigenous vegetation or Yes?  Canterbury gecko may be present. It is an indigenous species at its distribution Liz restricted to Canterbury and S limit within Canterbury Region or Marlborough. nationally.  No indigenous plant or invertebrate species at their distribution limits.

6. Indigenous vegetation or an association of Yes  The combination of common skink clade indigenous species that is distinctive, of Inv 5 and Canterbury gecko, if present, is not restricted occurrence, occurs within an distinctive or of restricted occurrence. originally rare ecosystem, or has  Rock face moth fauna is now of developed as a result of an unusual restricted occurrence and is part of a environmental factor or combination of nationally rare ecosystem (i.e. ‘basic factors. cliffs, scarps and tors’ in Williams et al. 2007). It is likely to occur here based on recent photographic evidence.

Diversity and Pattern

7. Indigenous vegetation or habitat of No  The site does not have a high diversity of indigenous fauna that contains a high indigenous plant species or habitat diversity of indigenous ecosystem or types. habitat types, indigenous taxa, or has  The site unlikely to have a high diversity changes in species composition reflecting of lizard or indigenous invertebrate the existence of diverse natural features or species. ecological gradients.

Ecological Context

8. Vegetation or habitat of indigenous fauna Yes?  The site is part of an important network that provides or contributes to an important Inv of rock face habitats for insect fauna ecological linkage or network, or provides across the Port Hills if rock face moth an important buffering function. populations are present.

9. A wetland which plays an important No  The site does not contain any wetlands. hydrological, biological or ecological role in the natural functioning of a river or coastal system.

10. Indigenous vegetation or habitat of Yes?  The site contains potential breeding and indigenous fauna that provides important Liz feeding habitats for lizards. If present, habitat (including refuges from predation, Inv populations are likely to be small due to or key habitat for feeding, breeding, or recent (i.e. post-quake) colonisation from resting) for indigenous species, either adjacent areas and low reproductive seasonally or permanently. rates.  The site is likely to provide permanent and important habitat for indigenous rock face moths.

5.5 Potential effects

5.5.1 Vegetation

The proposed remediation works at Shag Rock Reserve will result in the permanent destruction of the current vegetation cover at the site (although the vegetation on the cliff faces is not expected to be altered by the proposed works). The site does not contain any significant indigenous vegetation, however, as the original vegetation cover was destroyed over a century ago and only a few naturally occurring indigenous species are now present; these are all common and widespread in the Sumner- Redcliffs area (e.g. cabbage tree and large-leaved pōhuehue). Adverse effects on indigenous vegetation from the proposed works are therefore likely to be less than minor.

5.5.2 Lizards

The boulder fields and unmaintained vegetation now present in Shag Rock Reserve constitutes better habitat for lizards (particularly for skinks) than the manicured parkland that was present pre-quake. The effects of the proposed works at Shag Rock Reserve are unknown and could range from less than minor (if lizards are not present) to moderate (if small populations of either or both species are present).

5.5.3 Invertebrates

The broad area at the base of the cliffs covered in boulderfield and rock debris is now a well-vegetated mix of predominantly introduced weeds, mixed with a few indigenous species such as poroporo, ngaio and Senecio glomeratus. Based on recent surveys of similar areas nearby (see Wildland Consultants 2015), the invertebrate fauna of this area will lack diversity, as many of these weeds are from families of plants not represented in the New Zealand flora and most New Zealand insects are specialist feeders. Among the indigenous plants occurring the site, ngaio is likely to support a few indigenous beetles, bugs and moths, while Senecio glomeratus will be providing food for specialist Senecio moths such as the magpie moth (Nyctemera annulata). Likewise poroporo will be a foodplant for two moths; poroporo moth (Sceliodes cordalis) in its berries and the tiny gelechiid Symmetrischema plaesiosema boring in its stems. All of these moth species are widespread and abundant in the wider area, are good dispersers, and are not considered to be ecologically significant. Although the proposed works will result in the destruction of the existing vegetation and invertebrate habitats at the site, the effects on indigenous invertebrates are expected to be less than minor, as the works will not affect any significant invertebrate values.

Some of the steep rock faces at Shag Rock Reserve appear to have retained a cover of indigenous lichens, mosses and algae, and are highly likely to support specialised indigenous rock face moth species, which are considered to be ecologically significant (see Table 3). However, these rock faces are not expected to be altered further by the proposed works, therefore adverse effects on the indigenous invertebrates on the rock faces are expected to be less than minor.

5.6 Measures to avoid, remedy and/or mitigate potential adverse effects

5.6.1 Vegetation

No significant botanical values are present at Shag Rock Reserve, therefore it is not necessary to avoid, remedy and/or mitigate any potential adverse effects on vegetation. Nevertheless, after the remediation works have been carried out (i.e. re- contouring of the boulderfields, deposition of spoil from Deans Head, and erection of the bunds), revegetation of the site (or parts of the site) with ecologically appropriate indigenous plant species (determined in consultation with an ecologist) would be beneficial for restoring ecological values to the site and providing habitat for indigenous fauna (particularly birds and invertebrates).

5.6.2 Lizards

Remediation measures proposed for lizards are dealt with in a separate Lizard Management Plan (Lettink 2015). Briefly, the following action is recommended:

 Create new lizard habitat at Shag Rock Reserve. As part of the preparatory phase for geotechnical works at Deans head, the talus will be pulled back from the base of the cliff and contoured to form a loose bund along the front of the reserve (see Figure 3). Revegetation of the site will be subject to Health and Safety regulations (the area is a rockfall/cliff collapse hazard zone) and ecological constraints (e.g. the difficulties of establishing plants on talus). Revegetation could potentially be achieved by: (1) hydro-seeding with a mix of native plant species that are able to colonise talus and provide resources for lizards (food, shelter and protection from predators); and/or (2) natural colonisation by (predominantly introduced) plant species present nearby.

5.6.3 Invertebrates

The steep cliffs at Shag Rock Reserve could support ecologically significant indigenous rock face invertebrates (this was not able to be confirmed due to access restrictions). In order to conserve potentially significant invertebrate values, contractors should avoid damage or disturbance to rock walls at the site during implementation of the remediation works on the ground.

After the remediation works at Shag Rock Reserve have been completed, the human- made rock walls from Deans Head that currently support indigenous rock face moths should be relocated and carefully positioned in the Reserve (see recommended measures in the Deans Head section of this report for more details).

5.7 Conclusions

Shag Rock Reserve does not contain any significant indigenous vegetation, and the proposed remediation works will have less than minor effects on indigenous vegetation, therefore no mitigation measures are required. Nevertheless, if revegetation of the site is to be carried out, then the use of ecologically appropriate indigenous plant species (which will also provide habitat/food for indigenous fauna) is recommended.

Shag Rock Reserve could not be accessed due to safety constraints; thus its current faunal values could not be documented. Its lizard values remain unknown: potential habitat for Canterbury gecko has decreased (due to cliff collapse) and potential habitat for skinks has increased with the change from tidy parklands to boulder fields. This site provides an opportunity for the creation of new lizard and invertebrate habitat (described in Lettink 2015).

The steep rock walls of Shag Rock Reserve are likely to contain significant habitat for a range of both common and rare moth species that are rock face specialists. However, the remediation works are proposed to occur on the ground below the cliffs and are therefore not expected to affect these specialist rock face invertebrates. The ground at the site is likely to provide habitat for a range of common, opportunistic moths and other insect species, both indigenous and introduced, however none of these species are considered to be ecologically significant, and overall effects on invertebrates are expected to be less than minor.

6. MEASURES TO ADDRESS POTENTIAL ADVERSE EFFECTS A summary of measures suggested to address potential adverse effects resulting from the proposed remediation is provided below (Table 4).

Table 4: Measures suggested to avoid, remedy, and/or mitigate more than minor adverse effects on lizards and invertebrates resulting from the proposed works1.

Site Lizards Invertebrates Deans  Hydro-seed benched surfaces with  Prior to commencement of the works, Head drought-tolerant introduced where safe access is possible, rock grasses once house removal and walls to be removed should be earthworks have been completed. inspected by an ecologist (entomologist) This should provide suitable to determine the presence of indigenous habitat for common skink clade 5 rock face moths. within a relatively short time-frame (<3 years) and permit colonisation  Rock walls should be removed carefully by skinks persisting adjacent in order to minimise disturbance to areas. surface vegetation/habitats, and placed in Shag Rock Reserve in a vertical position (or close to) with the mossy side facing outwards. Ideally this work should be carried out in consultation with an ecologist on-site.  Removal of the rock walls should ideally be carried out from March to August, in order to minimise disturbance when moths are active.  Control of invasive weeds on the rock walls is recommended, as these will shade the rock faces and reduce habitat available for specialist rock face insects. Peacocks  Create new lizard habitat.  Gallop Redistribute talus to geotechnical specifications. Leaving the boulder fields in their current state, although best for lizards, is not an option because they provide a ramp that increases rockfall risk to road users. Revegetation could potentially be achieved by: (1) hydro-seeding with a mix of native plant species that are able to colonise talus and provide resources for lizards (food, shelter and protection from predators); and (2) natural colonisation by predominantly introduced plant species present in nearby areas.

1 No mitigation measures are proposed for vegetation, as potential adverse effects on indigenous vegetation are less than minor at all of the sites. 2 A herpetologist should be engaged to obtain Wildlife Act Authority from the Department of Conservation, including the preparation of a Lizard Management Plan. 3. A Restoration Plan for Shag Rock Reserve should be prepared by a suitably-qualified ecologist, with input from a herpetologist and entomologist.

ACKNOWLEDGEMENTS

We would like to thank Luci Swatton (Aurecon NZ Ltd) for accompanying us on the field visit in March, and CERA for permission to access the sites. We also thank Heather Holder- Lunn and Lynne Armitage (Christchurch City Council) for managing this complex project, and Gareth Taylor (Jacobs) for information on the proposed works. We are also grateful to Bryony McMillan, Alan Fife, and Jessica Beever (all of Landcare Research) for assistance with moss identification and information.

REFERENCES

Aurecon NZ Ltd 2014c: Deans Head Engineering Concept Summary. Memorandum to Lynne Armitage (Christchurch City Council) from Luci Swatton (Aurecon NZ Ltd) on 18 August 2014 (Reference 236152-18-173). Prepared for Christchurch City Council. 4 pp.

Christchurch City Council 2010: Christchurch City Council Operational Pest Management Plan (February 2010). 20 pp.

Davis M., Lettink M., and Patrick B. 2014: Sumner Road Re-opening Project. Assessment of Environmental Effects - Ecology. Prepared for Christchurch City Council. 62 pp.

Department of Conservation Herpetofauna Database (www.doc.govt.nz/nzherpatlas). de Lange P.J., Rolfe J.R., Champion P.D., Courtney S.P., Heenan P.B., Barkla J.W., Cameron E.K., Norton D.A., and Hitchmough R.A.. 2013: Conservation status of New Zealand indigenous vascular plants, 2012. New Zealand Threat Classification Series 3. Department of Conservation, Wellington. 70 pp.

Hitchmough R., Anderson P., Barr B., Monks J., Lettink M., Reardon J., Tocher M., and Whitaker T. 2013: Conservation status of New Zealand reptiles, 2012. New Zealand Threat Classification System Series 2. Department of Conservation, Wellington. 16 pp.

Hitchmough R., Dugdale J.S., Hoare R.J., and Patrick B.H. In Press: Conservation status of New Zealand Lepidoptera. New Zealand Threat Classification System Series, Department of Conservation, Wellington.

Howell C. 2008: Consolidated list of environmental weeds in New Zealand. DOC Research and Development Series 292. Department of Conservation, Wellington. 42 pp.

Lettink M. and Whitaker T. 2004: Lizards of Banks Peninsula. Department of Conservation, Christchurch.

Lettink M. 2012: Flora and fauna habitats on Banks Peninsula, Canterbury. Prepared for Environment Canterbury, Christchurch. 38 pp.

Lettink M. 2015: Lizard Management Plan for the proposed remediation works along the Sumner-Redcliffs section of the Sumner-Lyttelton Corridor, Christchurch. Report prepared for Christchurch City Council, Christchurch. 7 pp.

Liggins L., Chapple D.G., Daugherty C.H., and Ritchie P.A. 2008: A SINE of restricted gene flow across the Alpine Fault: phylogeography of the New Zealand common skink (Oligosoma nigriplantare polychroma). Molecular Ecology 17: 3668-3683.

Maw R. 2011: Canterbury Regional Pest Management Strategy 2011-2015. Report R11/23. Environment Canterbury, Christchurch. 148 pp.

McEwen W.M. 1987: Ecological Regions and Districts of New Zealand. Third revised edition in four 1:500,000 maps. Booklet to accompany Sheet 3: descriptions of districts in central New Zealand, from eastern Wairarapa to Akaroa, also Chathams, not shown on map. Publication No. 5 (in four parts). Part 3. New Zealand Biological Resources Centre, Department of Conservation, Wellington. 137 pp.

Schmechel F. (ed.) 2009: The War on Pests. Dealing to key pest plants and animals that threaten native species. A landowners’ guide for Banks Peninsula and Kaitorete Spit. Environment Canterbury, Christchurch. 74 pp.

Wildland Consultants 2013: Guidelines for the application of ecological significance criteria for indigenous vegetation and habitats of indigenous fauna in Canterbury Region. Wildland Consultants Contract Report No. 2289i. Prepared for Environment Canterbury, Christchurch. 19 pp.

Wildland Consultants 2015: Ecological assessment of the proposed remediation works on the Sumner-Redcliffs Road Corridor, Christchurch. Wildland Consultants Contract Report No. 3597a. Prepared for Christchurch City Council. 32 pp.

Williams P.A., Wiser S., Clarkson B., and Stanley M. 2007: New Zealand’s historically rare terrestrial ecosystems set in a physical and physiognomic framework. New Zealand Journal of Ecology 31(2): 199-128.

Wilson H.D. 1992: Banks Ecological Region. Protected Natural Areas Programme, Survey Report No. 21. Department of Conservation, Christchurch. 342 pp.

Wilson H.D. 1999: Naturalised vascular plants of Banks Peninsula. Canterbury Botanical Society Special Publication, Christchurch. 51 pp.

Wilson H.D. 2013: Plant Life on Banks Peninsula. Manuka Press, Cromwell. 411 pp.

APPENDIX 1

INDIGENOUS VASCULAR PLANT SPECIES LIST

Indigenous vascular plant species recorded at Deans Head remediation site on 25 March 2015 and Shag Rock Reserve on 15 October 2015. Key: P = planted individuals present, W = self-sown seedlings and/or saplings present.

A. Indigenous species that occur naturally in the Port Hills Ecological District (according to Wilson 1992).

Scientific Name Common Name Life Form Deans Shag Rock Head Reserve Cordyline australis Cabbage tree, tī kōuka Tree W P, W Dodonaea viscosa Akeake Tree P, W Muehlenbeckia australis Large-leaved pōhuehue Vine W W Myoporum laetum Ngaio Tree W P, W Olearia paniculata Akiraho Tree P Senecio glomeratus Native groundsel, fireweed Dicot herb W Solanum laciniatum Poroporo Shrub W

B. Indigenous species that are native to other parts of the country i.e. do not occur naturally in the Port Hills Ecological District (according to Wilson 1992).

Scientific Name Common Name Life Form Deans Shag Rock Head Reserve Coprosma repens Taupata Shrub W P, W Hebe spp. Various hebe cultivars Shrub P Hoheria populnea Lacebark, houhere Tree P Metrosideros excelsa Pōhutukawa Tree P Meryta sinclairii Puka Tree P Pittosporum crassifolium Karo Tree P, W

APPENDIX 2

INTRODUCED VASCULAR PLANT SPECIES LIST

Introduced vascular plant species recorded at Deans Head remediation site on 25 March 2015 and Shag Rock Reserve on 15 October 2015. Key: P = planted individuals present, W = self-sown seedlings and/or saplings present. NB. Only recognised pest plants or species with potential to spread were recorded.

Deans Shag Rock Scientific Name Common Name Life Form Pest Status Head Reserve Acer pseudoplatanus Sycamore Tree Biodiversity Protection Pest 1,2 W Aeonium haworthii Pinwheel aeonium Dicot herb Pest plant 3 W W Aloe arborescens Candelabra aloe Monocot W P? Aloe sp. aloe Monocot P? Aptenia cordifolia Heart-leaf ice plant Dicot herb W Argyranthemum frutescens Marguerite daisy Shrub W Berberis sp. Barberry Shrub P Centranthus ruber Spur valerian Dicot herb Pest plant 3,4,5 W W Chamaecytisus palmensis Tree lucerne Tree Pest plant 3 W Cheiranthus cheiri Wallflower Dicot herb Pest plant 4,5 W Chrysanthemoides monilifera Boneseed Shrub Containment Control Pest 1,4,5 W W Clematis vitalba Old man's beard Vine Containment Control pest 1,2,4 W W Cotoneaster franchetii Franchet's cotoneaster Shrub Restricted Pest 1,3 W Cotyledon orbiculata Pig's ear Dicot herb Pest plant 5 W W Cytisus scoparius Scotch broom Shrub Containment Control Pest 1 W W Drosanthemum floribundum Pale dew plant Dicot herb P, W Dryopteris filix-mas Male fern Fern Pest plant 2,3 W Echium candicans Pride of Madeira Dicot herb Pest plant W W Ehrharta erecta Veldt grass Grass Pest plant 3 W W Eucalyptus sp. Eucalyptus Tree P Foeniculum vulgare Fennel Dicot herb Pest plant 4,5 W W Hedera helix Ivy Vine Pest plant 3,5 W Lobularia maritima Alyssum Dicot herb W W Lupinus arboreus Tree lupin Shrub Restricted Pest 1,3 W Lycium ferocissimum Boxthorn Shrub W Malva sylvestris Large-flowered mallow Dicot herb W W

Deans Shag Rock Scientific Name Common Name Life Form Pest Status Head Reserve Oxalis articulata Sourgrass Dicot herb W Parthenocissus sp. Virginia creeper Vine P Phoenix canariensis Phoenix palm Monocot P Senecio elegans Purple groundsel Dicot herb W Solanum chenopodioides Velvety nightshade Dicot herb W Vinca major Periwinkle Dicot herb Pest plant 2,3 W W

1 Pest status in the Canterbury Regional Pest Management Strategy 2011-2015 (Maw 2011):  Containment Control Pest = the aim is to restrict the distribution or density of a particular (often widespread) pest to a specific area or density threshold, in order to minimise its impacts.  Biodiversity Protection Pest = a pest that poses a significant threat to biodiversity values in Canterbury. Targeted for control in High-Value Environmental Areas.  Restricted Pest = it is illegal to sell, propagate or disperse this species. 2 Listed as one of the 20 least desirable weeds on Banks Peninsula by Wilson (1999). 3 Listed as an environmental weed in Howell (2008). 4 Listed as a priority pest plant in Christchurch City Council’s Operational Pest Management Plan (Feb 2010). 5 Listed as a key threat to rock outcrops in Schmechel (2009).

APPENDIX 3

INVERTEBRATE SPECIES LIST

Invertebrate species (Class Insecta) recorded at Deans Head remediation site on 25 March 2015. Comments on host plants and regional distribution are also provided.

ORDER LEPIDOPTERA

Pieridae  Pieris rapae (white butterfly): accidently introduced species. Common along cliffs, where larvae feed on a range of crucifer herbs.

Geometridae  Epyaxa rosearia (common looper moth): larvae on herbs - both indigenous and introduced. Common and widespread, in both natural and suburban habitats.  Helastia cinerearia (grey looper moth): larvae on mosses on rock faces. Widespread and common species of rocky habitat. Present at both the Sumner end and at Deans Head.

Crambidae  Gadira petraula (rock face moth): larvae feeding on lichens under a sheet of silk on rock faces. Classified by Department of Conservation as “At Risk-Naturally Uncommon” (Hitchmough et al. in press). Banks Peninsula is its national stronghold, although it is only known here from six places. The female is flightless, so mobility of populations is severely restricted. Found only at Deans Head on human-made rock walls, which are extensive at this site. Both adults and larval working were found.  Orocrambus vittellus (common grassmoth): larvae on indigenous and introduced grasses. Widespread and common in natural and suburban grass habitats.  Orocrambus flexuosellus (common grassmoth): larvae on indigenous and introduced grasses. Widespread and common in natural and suburban grass habitats.

Gelechiidae  Kiwaia brontophora (speckled kiwaia): larvae on mosses such as Grimmia, which occur on rock faces. Reasonably widespread and common moth of rock faces, generally in natural setting. Present on human-made rock walls, which are extensive at Deans Head.

Tortricidae  Capua semiferana (leaf roller): a small endemic species that is typical of open areas including rocky sites. The larvae feed in dead leaf litter where they construct silk tunnels. Widespread and common.

ORDER COLEOPTERA

Carabidae  Laemostenus complanatus (Cosmopolitan ground beetle): a population of this cosmopolitan carabid beetle was found at the base of Deans Head under debris and rocks. Widespread in suburban habitats nationwide.