Before a Special Tribunal
Under the Resource Management Act 1991
In the matter of an application for a Water Conservation Order for the Ngaruroro River and Clive River
Statement of evidence of Rachel Katherine McClellan on behalf of the New Zealand Fish and Game Council; Hawke's Bay Fish and Game Council; Royal Forest and Bird Protection Society of New Zealand; Jet Boating New Zealand; Whitewater NZ Incorporated; and Operation Pātiki Ngāti Hori ki Kohupātiki
12 December 2018
Introduction
1 My name is Rachel McClellan. I am the principal avifauna ecologist with Wildland Consultants Ltd (Wildlands), based in Wellington. I have worked for Wildlands for nine years. I have undertaken avifauna work across New Zealand, including survey and monitoring, assessments of effects, threatened species monitoring and management, development of ecological significance criteria, and strategic and restoration plan development and implementation.
2 I have been engaged by Royal Forest and Bird Protection Society of New Zealand to provide expert evidence on birds in relation to the application of a Conservation Order for the Ngaruroro River, Hawke's Bay.
3 I visited sites along the length of the upper and lower Ngaruroro River on 3 October 2017.
Qualifications and experience
4 I have the following qualifications and experience:
(a) Degrees of Bachelor of Science in Zoology and Botany from Victoria University;
(b) Master of Conservation Science (with Distinction). My thesis was on the breeding biology of the Nationally Vulnerable flesh-footed shearwater (Puffinus carneipus) on Karewa Island (Victoria University, 1996); and
(c) PhD in Zoology. My thesis investigated the ecology and management of the Nationally Critical black-billed gull (Larus bulleri) (University of Otago, 2009).
5 I am a member of the New Zealand Ecological Society and Birds New Zealand (brand name of the Ornithological Society of New Zealand).
6 I have prepared expert evidence for 15 Council, Environment Court, and Tribunal hearings addressing issues such as river conservation orders, coastal subdivisions, mining applications, wind farms, hydropower proposals, and council plan changes. Hearings have included the provision of avifauna evidence for the Oreti River Conservation Order hearing (for Fish and Game New Zealand), and for Meridian Energy's North Bank Tunnel proposal on the braided Waitaki River (for the Lower Waitaki River Management Society).
7 I have considerable experience in river bird, seabird and shorebird ecology. I completed my PhD on the Nationally Critical black-billed gull, which examined population trends, the impacts of introduced and native predators, the impact of flows on productivity, and the species' relationship with agricultural ecosystems.
12000434 | 4075529 page 1
Since then, I have remained involved with the monitoring and management of threatened bird species on braided rivers, including providing expert advice for the Department of Conservation's braided rivers management plan, and the analysis of 50 years of black-billed gull monitoring data from South Island rivers.
8 Examples of other projects include: review of the Department of Conservation's Fiordland crested penguin (Eudyptes pachyrhynchus) monitoring programme; review of the Yellow-eyed Penguin Trust's work on yellow-eyed penguins (Megadyptes antipodes) on Rakiura (Stewart Island); avifauna (including seabird) restoration and management components of the Department of Conservation's Dusky Sound Restoration and Conservation plan, and the Project Janszoon restoration plan for Abel Tasman National Park; restoration plan for Long Point, Catlins, including reintroduction of seabird species including albatross; aerial surveys of Canterbury rivers for black-billed gulls; and provision of expert evidence on the effects of the Rena wreck on seabirds and shorebirds.
9 I presented evidence to this Special Tribunal regarding the bird habitat values of the upper Ngaruroro as part of the Stage 1 Hearing.
10 While this is not a hearing before the Environment Court, I confirm that I have read the code of conduct for expert witnesses contained in the Environment Court Consolidated Practice Note (2014). I have complied with it when preparing my written statement of evidence and I agree to comply with it when presenting evidence. I confirm that the evidence and the opinions I have expressed in my evidence are within my area of expertise. I have not omitted to consider material facts known to me that might alter or detract from the opinions that I express.
Scope of evidence
11 For the purpose of the Stage 2 hearing of this Water Conservation Order application, I have been directed to provide evidence on bird habitat of the lower Ngaruroro River. The scope of this statement of evidence is as follows:
(a) Overview of bird habitats of the Ngaruroro catchment;
(b) Overview of the birds of the Ngaruroro catchment;
(c) Relevant surveys and reports of Ngaruroro River avifauna;
(d) The ecological significance of the habitats and bird species of the lower Ngaruroro;
(e) Comparison with other braided rivers protected by Water Conservation Orders;
12000434 | 4075529 page 2
(f) The potential effects of river modifications on the habitats and bird species of the lower Ngaruroro; and
(g) The lower Ngaruroro as outstanding habitat for birds.
Summary
12 The lower Ngaruroro is the second largest braided river in the North Island, a historically rare ecosystem in New Zealand, and rare internationally.
13 The bird habitats of the lower Ngaruroro are of an outstanding nature as they:
(a) Support a high diversity of waterbirds, including South Island pied oystercatcher, which breeds on no other river in the North Island, and black-billed gull (Nationally Critical), which is rare in the North Island;
(b) Support one of the largest known populations in New Zealand of each of banded dotterel (Nationally Vulnerable), black-fronted dotterel (At Risk- Naturally Uncommon), and pied stilt (Not Threatened);
(c) Support greater than 5% of the national populations of banded dotterel and black-fronted dotterel, and more than 1% of pied stilt population; and
(d) Are part of a system of wetlands in the lower Ngaruroro area, including Waitangi Wetland, that may support more than 1% of the Australasian bittern population (Nationally Critical).
Overview of bird habitats of the Ngaruroro River and its tributaries
14 The Ngaruroro River is one of the North Island's largest braided rivers1. The river can be divided into five main sections:
(a) The upper reaches of the river above the gorge at Whanawhana (and its tributaries) which are mostly single channel. The upper reaches and tributaries flow through steep, rugged country which mostly comprises regenerating scrub and forest and some commercial pine plantations. The upper Ngaruroro and its many tributaries support a significant population of blue duck or whio, a specialist species of waterfowl dependent on high quality, fast flowing water;
(b) The reaches between Whanawhana and the Fernhill Bridge which are extensively braided. Hundreds of hectares of bare gravels are available for New Zealand's specialist braided river bird species, all of which are
1 Wilson G. 2001: National distribution of braided rivers and the extent of vegetation colonisation. Landcare Research Contract Report LC0001/068. Prepared for the Department of Conservation, Twizel.
12000434 | 4075529 page 3
Threatened or At Risk. At least one tributary of this reach, Big Hill Stream, supports a small population of whio. This section also includes the only significant freshwater swamp associated with a river in Hawke's Bay2. Pigsty Swamp is an oxbow wetland caused by movement of the river away from the original channel, and is located approximately six kilometres downstream of the Whanawhana cableway, and drains to the river mainstem. A number of specialist wetland bird species such as Australasian bittern have been reported from this wetland;
(c) The reach between Fernhill and the Chesterhope Bridge, which is less braided and mostly single channel, which also contains wide expanses of bare gravels that support braided river bird species;
(d) The reach between the Chesterhope Bridge and the Waitangi Estuary and associated wetlands, which is largely channelised; and
(e) The Waitangi Estuary and associated wetlands, including the gravel bars, and the Horseshoe Wetland. A diverse range of bird species are found at the estuary. Some bird species that roost or breed at this location will forage in the lower Ngaruroro, just as birds breeding in the lower Ngaruroro may feed in the estuary and wetlands.
15 This evidence addresses the bird values of the lower Ngaruroro River.
Overview of the bird community of the Ngaruroro catchment
16 The bird community of the Ngaruroro catchment has been described by two authors, Dr Brent Stephenson3 and Dr Richard Seaton4, who both include terrestrial birds in their species lists. Dr Stephenson lists 83 bird species that inhabit the upper and lower riverbed, riparian habitats, freshwater wetlands, and the Waitangi Estuary and associated habitats. Dr Seaton lists 93 species that have been recorded from the Ngaruroro catchment since the early 1960s; his list includes some species that are now unlikely to be present (such as brown kiwi). Both authors include birds that are rare visitors to the river and estuary. I provide a combined list of all species in Appendix 1.
17 The combined list contains 58 bird species that are dependent on the river for some stage of their lifecycle. I have called these species 'waterbirds'. This list
2 Parrish G.R. 1988: Wildlife and wildlife habitat of Hawke's Bay rivers. Science & Research Series 2. Department of Conservation, Wellington.
3 Stephenson B.M 2010: Final report – baseline study and assessment of effects on braided riverbed bird communities. Unpublished report, Eco-Vista Photography & Research Ltd. 59p
4 Seaton R. 2014: Assessment of outstanding avifauna values on the Ngaruroro River. Report prepared for the New Zealand Forest and Bird Protection Society. The Catalyst Group. 13p.
12000434 | 4075529 page 4
includes, for example, seabirds that venture into estuarine habitats such as the Australasian gannet (Morus serrator), shags, herons, oystercatchers, gulls, terns, international migratory waders, and waterfowl. Most of these species are restricted to the estuarine and braided habitats of the lower Ngaruroro River.
18 In contrast, the upper Ngaruroro and its tributaries support significantly fewer species of waterbirds. The primary species of conservation importance known from the upper Ngaruroro is blue duck. The upper Ngaruroro was addressed in my evidence for the Stage 1 Hearing.
Relevant surveys and reports of lower Ngaruroro avifauna
19 Six historical surveys of lower Ngaruroro River waterbirds have been undertaken in the years 1962, 1967, 1972, 1984, 1986, and 1993. Surveys in 1962, 1967, and 1972 were undertaken by the Ornithological Society of New Zealand (OSNZ; now Birds New Zealand); in 1984 and 1986 by the New Zealand Wildlife Service; and in 1993 by the Department of Conservation. The OSNZ surveys and Wildlife Service surveys are summarised in Parrish (1998)5.
20 More recently, a section of the lower Ngaruroro between Otamauri Stream and Maraekakaho, a distance of some 17 kilometres, was surveyed in 2010 by Dr Brent Stephenson (approximately one third of the lower river)6. Stephenson summarises all historical surveys in his report.
21 In 2016, Hawke's Bay Regional Council undertook an aerial survey of several of the main rivers, as well as the coast, for black-billed gulls.
22 Finally, a survey of the lower Ngaruroro from the Whanawhana cableway to State Highway 3 was undertaken in November 2018 by the Department of Conservation and Birds New Zealand.
23 In contrast to the intermittent surveys of the lower Ngaruroro, the birds of Waitangi Estuary and its associated wetlands have been regularly surveyed for decades. For example, annual winter and summer counts from Ahuriri Estuary, Westshore Lagoon, East Clive, Waitangi Estuary, and Tukituki Estuary between 1983 and 2003 have been analysed as part of two scientific publications assessing the stability of national wader populations7,8.
5 Parrish G.R. 1988: Wildlife and wildlife habitat of Hawke's Bay rivers. Science & Research Series 2. Department of Conservation, Wellington.
6 Stephenson B.M 2010: Final report – baseline study and assessment of effects on braided riverbed bird communities. Unpublished report, Eco-Vista Photography & Research Ltd. 59p.
7 Sagar P.M., Shankar U. and Brown S. 1999: Distribution and numbers of waders in New Zealand, 1983- 1994. Notornis 46: 1-43.
12000434 | 4075529 page 5
24 In addition to the surveys, several assessments of the biodiversity values and, in particular, the bird values of the Ngaruroro have been completed. The first of these was the New Zealand Wildlife Service's report in 1998 that, in addition to summarising survey results of the Tukituki, Tutaekuri, Ngaruroro and Mohaka, also assessed the values of those rivers using the Sites of Special Wildlife Interest (SSWI) criteria.
25 The second assessment was done as part of the Protected Natural Areas Programme in 1993, involving the survey of remaining natural areas within the Heretaunga Ecological District.
26 A further assessment was undertaken in 2012 using the River Values Assessment System (RiVAS), which applied criteria to assess existing value and potential value of every river in the Hawke's Bay for birds. The SSWI and RiVAS assessments are discussed in greater detail in paragraphs 82-95.
27 As previously mentioned, two unpublished reports by Stephenson (2010)9 and Seaton (2014)10, specifically discuss the bird values of the upper and lower Ngaruroro River.
28 Lastly, Hawke's Bay Regional Council has published or commissioned several reports which summarise habitat and fauna values, condition, and management of the Ngaruroro River and its estuary. These include publications relating to the management of water within the Tutaekuri, Ahuriri, Ngaruroro and Karamu catchments (or TANK)11, a biodiversity inventory for the region12, and the Ecological Management and Enhancement plan for the Ngaruroro River flood protection and drainage scheme13.
8 Southey I. 2009: Numbers of waders in New Zealand 1994-2003. DOC Research & Development Series 308. Department of Conservation, Wellington. 70 p.
9 Stephenson B.M 2010: Final report – baseline study and assessment of effects on braided riverbed bird communities. Unpublished report, Eco-Vista Photography & Research Ltd. 59p.
10 Seaton R. 2014: Assessment of outstanding avifauna values on the Ngaruroro River. Report prepared for the New Zealand Forest and Bird Protection Society. The Catalyst Group. 13p.
11 For example, Madaraz-Smith A., Wade O., Wade H. and A. Hicks 2016: The estuaries of the TANK catchments: Ahuriri and Waitangi estuaries. HBRC Report No. RM 16-20. Hawke's Bay Regional Council, Napier.
12 Hashiba K., Wade O. and W. Hesketh 2016: Hawke's Bay biodiversity inventory: current state of knowledge. HBRC Report No. RM 13/23–4554. Hawke's Bay Regional Council, Napier.
13 MWH 2011: Ngaruroro River flood protection and drainage scheme – Ecological management and enhancement plan. HBRC Report No. AM 11-04. Prepared for Hawke's Bay Regional Council, Napier.
12000434 | 4075529 page 6
The Ngaruroro in the context of New Zealand's braided rivers
29 Braided riverbeds are considered a historically rare ecosystem in New Zealand14. Braided rivers like the lower Ngaruroro are mostly found in erosion-prone areas around the world, being most common in parts of North America, the Himalayas, the Artic, and New Zealand15. Globally, the lower reaches of braided rivers are often extensively modified by impounding of water, modification of margins, and the taking of surface and ground waters16. New Zealand is no exception to this, and there are extremely few braided river systems in New Zealand that retain indigenous riparian vegetation, have limited invasive weed issues, and are free from water abstraction.
30 One hundred and sixty-three rivers have been identified as having one or more areas of braided habitat along their length; almost 80% of these rivers are located in the Canterbury and West Coast regions17. In contrast, the North Island has only 31 rivers with braided habitat, or 19% of the national total. Ten of these rivers are in the Gisborne and Hawke's Bay regions. The majority of these North Island rivers have a relatively small amount of braided habitat, generally less than c.500 hectares. The total area of North Island braided rivers is estimated to be 2.2% of the total national area18. The table below lists the details of the five North Island rivers with the greatest amount of habitat and compares those to the five largest braided rivers in New Zealand, including the iconic Rakaia River.
14 Williams, P.A., Wiser, S., Clarkson, B. and Stanley, M.C., 2007. New Zealand's historically rare terrestrial ecosystems set in a physical and physiognomic framework. New Zealand Journal of Ecology, pp.119-128.
15 O'Donnell C.F.J., Sanders M., Woolmore C. and Maloney R.F. 2016: Management and research priorities for conserving biodiversity on New Zealand's braided rivers. Department of Conservation, Wellington, New Zealand. 46 p.
16 Gray D. and Harding J.S. 2009: Braided river benthic diversity at multiple spatial scales: a hierarchical analysis of β diversity in complex floodplain systems. Journal of the North American Benthological Society, 28: 537-551.
17 Wilson G. 2001: National distribution of braided rivers and the extent of vegetation colonisation. Landcare Research Contract Report LC0001/068. Prepared for the Department of Conservation, Twizel.
18 O'Donnell C.F.J., Sanders M., Woolmore C. and Maloney R.F. 2016: Management and research priorities for conserving biodiversity on New Zealand's braided rivers. Department of Conservation, Wellington, New Zealand. 46 p.
12000434 | 4075529 page 7
Table 1: Largest braided rivers in the North and South Islands by area (data from Wilson 2001) 19
Region Total Habitat (ha) Amount of River Unvegetated or Open Habitat (ha) North Island Tukituki Hawke's Bay 5,589 2,367 Ngaruroro Hawke's Bay 3,500 1,597 Waiapu Gisborne 2,511 2,163 Rangitikei Wanganui-Manawatu 2,093 842 Tutaekuri Hawke's Bay 813 285 South Island Rakaia Canterbury 32,102 21,853 Rangitata Canterbury 18,091 11,249 Waimakariri Canterbury 14,349 10,487 Waitaki Canterbury 8,104 3,509 Waiau Canterbury 7,413 5,389
31 The Ngaruroro is the second largest braided river in the North Island by area, and the seventeenth largest braided river in the country of a total of 163 braided rivers.
32 The lower Ngaruroro provides a variety of habitats that are used by different groups or guilds of bird species20. The shag species are open water divers, taking fish or invertebrates from deep channels. Deep water waders, such as oystercatchers, stilts and herons, have long legs and can take advantage of deeper waters in the river. Short-legged waders like dotterels are restricted to shallower water along the edges of channels and backwaters. Swans, geese and most duck species dabble while floating in slower moving waters of rivers, or graze vegetation including pasture. Terns and black-billed gull can take invertebrates on the wing or from the surface of the water, though both will also wade.
33 Braided rivers also provide a variety of breeding habitats for the above species. Shags will often nest and roost alongside rivers in tall trees such as willow, but also in shrubs, and sometimes on the ground in wetlands or on cliffs. Riparian vegetation is mostly used by waterfowl. The open, bare gravel of braided riverbeds is used for nesting by species such as dotterels, oystercatchers, terns and gulls.
19 Gisborne's Waiapu River has the highest suspended sediment yield of any river in New Zealand, and one of the highest in the world, due to forest clearance in the catchment and excessive erosion rates. Canterbury's Waitaki River flow is entirely managed via a system of hydrodams.
20 O'Donnell C. 2004: River bird communities. In: Harding J., Mosely P., Pearson C. and Sorrell B. Freshwaters of New Zealand. New Zealand Hydrological Society and the New Zealand Limnological Society.
12000434 | 4075529 page 8
34 The lower Ngaruroro, and other braided rivers of the North Island, share some differences from South Island braided rivers in that they do not support breeding populations of some braided river specialists such as the Nationally Critical black stilt and the Nationally Endangered black-fronted tern, and hold very small numbers of the Nationally Critical black-billed gull.
35 However, the lower Ngaruroro stands out from the crowd as the only North Island river with a breeding population of South Island pied oystercatcher (At Risk- Declining), one of very few North Island rivers that regularly support black-billed gull, one of the first known locations of breeding black-fronted dotterel (At Risk- Naturally Uncommon) which has now developed into one of New Zealand's most important populations, and one of the largest populations of banded dotterel (Threatened-Nationally Vulnerable) and pied stilt (Not Threatened) in New Zealand. I will discuss these in detail in subsequent sections.
The bird community of the lower Ngaruroro River
36 As noted above, the bird community of the entire Ngaruroro River has been described by two authors. Stephenson lists 83 bird species that inhabit the riverbed, riparian habitats, freshwater wetlands, and the Waitangi Estuary and associated habitats. Seaton lists 93 species that have been recorded from the catchment since the early 1960s, and includes some species that are now unlikely to be present (such as brown kiwi). Both authors include birds that are rare visitors to the river and estuary. I provide a combined list of all species in Appendix 1.
37 I have addressed the national significance of the upper Ngaruroro and its tributaries in detail in my evidence for the first hearing. I will briefly discuss the significance of other habitats and bird species of the wider Ngaruroro area in paragraph 79. I realise that this hearing is not concerned with the Ngaruroro below the inland limit of the coastal marine area. However, I consider it important to at least briefly address the avifauna values of the estuary and associated wetlands, as some bird species present in the lower Ngaruroro are likely to use these habitats, and water management in the upper and lower Ngaruroro has the potential to affect these values.
38 The lower Ngaruroro River supports regular populations of 14 waterbird species, 12 of which are indigenous. Of those, five to six species are ecologically significant: black-billed gull (Nationally Critical), banded dotterel (Nationally Vulnerable), South Island pied oystercatcher (At Risk-Declining), black-fronted dotterel (At Risk-Naturally Uncommon), pied stilt (Not Threatened), and Australasian bittern (Nationally Critical). I will discuss each in turn in the following sections.
12000434 | 4075529 page 9
39 I use 1% and 5% national population thresholds for determining ecological significance in the following paragraphs. The 1% threshold derives from one of the criteria developed to identify Wetlands of International Importance (the "Ramsar List"; see paragraphs 97-99). The threshold has also been adopted by BirdLife International in its programme to identify globally Important Bird or Biodiversity Areas (or IBAs), where a site is known or thought to hold congregations of ≥1% of the global population of one or more species on a regular or predictable basis. Over 12,000 IBAs have now been identified around the world including New Zealand.
40 The 5% level is a threshold that has been used in several applications for Water Conservation Orders in New Zealand as representing an outstanding habitat.
12000434 | 4075529 page 10
Table 2: Counts of waterbird species in the lower Ngaruroro River: 1962-2018
Species Threat Classification 1962 1967 1972 1984 1986 1993 2010 2018 Black-billed gull Threatened-Nationally Critical 0 16 16 25 8 15 153 263 Grey duck Threatened-Nationally Critical 0 23 0 0 0 0 0 Banded dotterel Threatened-Nationally Vulnerable 514 246+ 216+ 438 480 570 253 1,101 Wrybill Threatened-Nationally Vulnerable 0 0 0 0 1 0 0 South Island pied oystercatcher At Risk-Declining 0 0 0 10 8 8 5+ 46 Black-fronted dotterel At Risk-Naturally Uncommon 39 96 134 127 145 53 200 Black shag At Risk-Naturally Uncommon 18 14 10 3 5 3 17 Little black shag At Risk-Naturally Uncommon 0 16 1 1 * 0 0 Australasian shoveler Not Threatened 7 0 7 0 0 0 0 Grey teal Not Threatened 0 0 0 4 4 0 77 Little shag Not Threatened 9 24 7 present 12 4 7 Paradise shelduck Not Threatened 111 108 64 183 150 163 88 303 Pied stilt Not Threatened 323 181+ 173+ 461 220 270 163 559 Southern black-backed gull Not Threatened 2,125 5,032+ 1,600 2,056 2,134 1,739 570 2,320 Spur-winged plover Not Threatened 0 0 0 52 56 551 161 252 White-faced heron Not Threatened 7 10 13 2 10 14 23 Canada goose Introduced 3 0 0 1 * 0 20 Mallard Introduced 56 29+ 50+ 14 31 32 92 NOTES: Approximately 49 kilometres surveyed in all years except 2010 when c.12 kilometres surveyed. 2018 survey used 2-3 observers per reach following best practise guidelines for wide braided rivers; previous surveys appear to have used a single observer. Empty cells signify no data available. '+' sign indicates observers were not confident all individuals had been sighted.
12000434 | 4075529 page 11
Black-billed gull (Threatened-Nationally Critical)
41 Black-billed gull (Larus bulleri) is one of New Zealand's most threatened bird species. Unlike most Nationally Critical bird taxa, it still has a large population that numbers in the tens of thousands, but has undergone a rapid decline. Recent modelling of South Island data across 52 years (1962-2014) from 30 South Island rivers predicts a continuing decline of approximately 75% over the next 30 years21.
42 Despite undergoing widespread decline in the South Island, black-billed gull have increased their range in the North Island in recent decades: black-billed gulls were first observed breeding in the North Island in 1932 with red-billed gulls in Lake Rotorua; in 1954 colonies were found at Gisborne Harbour and the Ngaruroro River mouth; a colony was observed on Matakana Island in Tauranga Harbour in 1967; breeding was confirmed on the Manawatu River by 1972; and nesting was not observed around the Auckland area until 199122. However, the increasing distribution does not appear to be associated with increasing abundance in the North Island23.
43 Most recently, a national census of black-billed gulls in 2016-2017 recorded a national total of 60,256 nests, of which 992 nests, or 1.6%, were in the North Island24. Only 19 nests were found in the Hawke's Bay region (main rivers and coastline were surveyed).
44 However, previous records in the Hawke's Bay have recorded some of the largest colonies in the North Island, such as the Ngaruroro River (1980, 270 birds; 2009, 150 birds), the Waitangi Estuary (1997, 250 birds), and Napier Wharf (2015, 150 birds).
45 The November 2018 survey of the lower Ngaruroro recorded a colony of 263 birds in the section between Pigsty Swamp and Whakamarumaru. This is one of the largest colonies ever recorded in the Hawke's Bay. The Ngaruroro and the Waitangi estuary are often used by black-billed gulls, although not every year. At Waitangi Estuary, black-billed gulls nest on the raised gravel beach near the river mouth. When nesting on the lower Ngaruroro itself, colonies have generally been
21 Wildland Consultants (McClellan R.K. and Smith D.V.S) 2015: Population trends of black-billed gulls (Larus bulleri) on South Island rivers 1962-2014). Wildland Consultants Report No. 3442. Prepared for Department of Conservation, Christchurch. 21 pp.
22 Southey I. 2007: Black-billed gulls: another threatened species in the Firth of Thames. Miranda News.
23 McClellan, R.K.; Habraken, A. 2013 [updated 2017]. Black-billed gull. In Miskelly, C.M. (ed.) New Zealand Birds Online. www.nzbirdsonline.org.nz
24 Mischler C. 2017: Estimating the breeding population of black-billed gulls Larus bulleri in New Zealand, and methods for future count surveys. Notornis 65: 67-83.
12000434 | 4075529 page 12
located several kilometres up river, often near the Mangatahi Stream confluence. In some years, such as 2018, the numbers of black-billed gulls present on the river or at the river mouth would comprise a significant proportion of the total North Island population.
46 The unpredictable presence of black-billed gulls is characteristic of the species. The species does not necessarily re-use colony sites. Individuals can move between rivers both within seasons and between years; rivers can have no gulls in some years, and gulls in others25. For example, two important Canterbury rivers for black-billed gulls are the Waiau and Ashburton. The Waiau supported no gulls in 2014, 1,181 nests in a single colony in 2015, and 511 nests in three colonies in 2016. The Ashburton supported 727 nests in 2015, and 4,686 nests in 2016 (no survey was conducted in 2014)26.
47 No location in the North Island meets the 1% threshold for black-billed gulls, and it is possible that such a threshold may never be met anywhere within the North Island. However, in my opinion, regularly used sites which support larger colonies within the North Island, such as the lower Ngaruroro, should be regarded as nationally important as the success of larger colonies may help maintain the species' population in the North Island. This is because larger colonies may have higher productivity than smaller colonies; a finding from my PhD research on black-billed gulls in Southland27, and recently supported by research on black- fronted terns28.
48 The regular presence of black-billed gull colonies on the river adds considerably to the outstanding bird habitats of the lower Ngaruroro.
Banded dotterel (Threatened-Nationally Vulnerable)
49 Banded dotterel (Charadrius bicinctus bicinctus) is an endemic species that breeds throughout New Zealand, from coastal beaches, to inland rivers, to terrestrial habitats such as the Central Plateau. On rivers, the solitary nests of banded dotterels tend to be on sparsely vegetated gravels. An unusual feature of the species is that birds from different areas have different post-breeding
25 McClellan R.K. 2008: Ecology and management of the black-billed gull in Southland. PhD thesis. Otago University.
26 Mischler C. 2017: Estimating the breeding population of black-billed gulls Larus bulleri in New Zealand, and methods for future count surveys. Notornis 65: 67-83.
27 McClellan R.K. 2008: Ecology and management of the black-billed gull in Southland. PhD thesis. Otago University.
28 Schlesselmann A-K.V., O'Donnell C.F.J., Monks J.M. and Robertson B.C. 2018: Clearing islands as refugia for black-fronted tern (Chlidonias albostriatus) breeding colonies in braided rivers. New Zealand Journal of Ecology 42.
12000434 | 4075529 page 13
movements. Those that breed at coastal locations tend to be sedentary, and remain in much the same location throughout the year. In contrast, those breeding on rivers or at other inland locations are mostly migratory. For example, banding results show that birds from Hawke's Bay rivers mostly move to northern New Zealand, to estuaries and harbours from the Bay of Plenty through to Auckland and Northland; and birds breeding in the Mackenzie Basin mostly migrate to Tasmania and southeast Australia29.
50 Banded dotterel is a threatened species, considered to be in decline due to the ongoing impacts of terrestrial predators such as cats, mustelids, rats and hedgehogs. It is listed as Nationally Vulnerable as it is considered to meet the criterion of a population of 5,000-20,000 mature individuals with a predicted decline of 30-70% in three generations. The 'Waterbird Population Estimates' (WPE) online database30 provides a considerably higher estimate for the species, at 50,000 birds, but is estimated from papers published in 200631.
51 The banded dotterel population on the lower Ngaruroro has been surveyed on six occasions between 1962 and 1993, and most recently in 2018. The number of banded dotterels varied between 246+ and 570 birds during the early surveys (see Table 2). Stephenson surveyed a 12-kilometre section of the river in 2010, and counted a similar number of dotterel within the same section compared to the 1984 and 1993 surveys32. However, the 2018 survey found 1,101 banded dotterels, twice the number of birds as any previous count.
52 The 2018 count was undertaken by two to three observers where river sections were particularly wide, which is the recommended method for surveying wide braided rivers33, such as the Ngaruroro. It appears that only single observers were used in the historical surveys, which is likely to be largely responsible for the large increase in banded dotterel counts which are very hard to see from a significant distance. The 2018 count is therefore a much more accurate account of the waterbird population of the lower Ngaruroro River.
29 Pierce R. 1999: Regional patterns of migration in the banded dotterel (Charadrius bicinctus bicinctus). Notornis 46: 101-122.
30 http://wpe.wetlands.org/ This database provides current and historic estimates, trends and 1% thresholds for over 800 waterbird species and 2,300 biogeographic populations worldwide, in part to support the work of the Ramsar Convention.
31 Wetlands International (2017). "Waterbird Population Estimates". Retrieved from wpe.wetlands.org on Friday 22 Sep 2017
32 Stephenson B.M 2010: Final report – baseline study and assessment of effects on braided riverbed bird communities. Unpublished report, Eco-Vista Photography & Research Ltd. 59p.
33 O'Donnell C.F.J. and Moore S.G.M. 1983: The wildlife and conservation of braided river systems in Canterbury. Fauna Survey Unit Report No. 33, NZ Wildlife Service, Department of Internal Affairs.
12000434 | 4075529 page 14
53 Using the more recent estimate of a maximum of 20,000 mature individuals, and the most recent count of 1,101 birds, the lower Ngaruroro holds approximately 5.6% of the national population. Using the WPE estimate, the river's population is approximately 2.2%.
Table 3: Summary of selected banded dotterel counts from Hawke's Bay and other New Zealand rivers
Mean Count of Mean Number of Banded Years of Survey Length Banded Dotterel per River Dotterel Survey (km) Kilometre (standard (standard deviation) deviation) Hawke's Bay Ngaruroro 1962, 1984, 49 684.3 (362.8) 14.0 (7.4) 2018 2018 only 49 1,101 22.5 Tutaekuri 1962, 1967, 41 270.5 (84.8) 6.6 (2.1) 1972, 1984 Tukituki 1967, 1972, 144 591.0 (335.9) 4.1 (2.3) 1984 Wairarapa Wairarapa rivers 2017 only Range 3.5-82.3 Overall mean Overall mean 1.8 (11 rivers) 34.4 (53.9) (2.6) Wellington/Kapiti Otaki 2012. 2013, 33.7 (14.0) 2.9 (1.2) 2014 Canterbury Upper Rangitata 2008, 2010, 18-39 362.3 (116.5) 14.1 (5.8) 2012 Lower Rangitata 2007, 2009 37-46 57.5 (3.5) 1.4 (0.1)
Lower 2007, 2008, 41 390.0 (131.9) 9.6 (3.3) Waimakariri 2009 Lower Rakaia 2006, 2007, 36-39 226.3 (80.3) 5.9 (1.9) 2009 Lower Hurunui 2008, 2009, 72 214.7 (22.1) 3.0 (0.3) 2010 Upper Waitaki 1991-1994 Range 9.0-77.2 Range of 14.4 (10.5) based on Basin (11 rivers) minimum counts minimum counts 18-599
54 Table 3 provides some context with which to assess the relative importance of the Ngaruroro River for banded dotterel. The table summarises count data from a number of rivers throughout New Zealand for more than one year where possible (as counts can vary markedly between years)34. I have attempted to include
34 Hawke's Bay counts are from Parrish (1998) and include all raw data available within the report, and unpublished Department of Conservation data from 2018. Canterbury counts are unpublished Department of Conservation data; years included are those held by myself for previous research. Wairarapa and Otaki counts are from McArthur N. and Burgin D 2017: Wairarapa river bird surveys project – Regional summary report. Client report prepared for Great Wellington Regional Council, Wildlife Management International Ltd, Blenheim, and McArthur N., Small D. and Govella S. 2015: Baseline monitoring of the birds of the Ōtaki, Waikanae and Hutt Rivers, 2012-2015. Greater Wellington Regional Council, Publication No. GW/ESCI-T-15/42, Wellington. Waitaki Basin data taken from Maloney R.F., Rebergen A.L., Nilsson R.J. and Wells N.J., 1997: Bird density and diversity, in braided river beds in the Upper Waitaki Basin, South Island, New Zealand. Notornis 44: 219-232.
12000434 | 4075529 page 15
known and potentially important braided rivers for avifauna from around New Zealand, including rivers with Water Conservation Orders such as the Rakaia and Rangitata. I could not find any data for the Rangitikei River, the fourth largest of the North Island's braided rivers (despite communications with several knowledgeable people). The table shows the mean count and the mean number of banded dotterel per kilometre. This latter measure does not take into account the width of the rivers which can vary significantly.
55 The data above show that the Ngaruroro supports a very large population of banded dotterel, possibly larger than many of the major braided river systems in Canterbury, including the Rakaia and Rangitata, both of which have Water Conservation Orders which recognise outstanding bird habitat values. A survey of the Tukituki/Waipawa River in 1984 recorded 963 banded dotterel; this river clearly also supports a very large population, possibly comparable to the Ngaruroro.
56 Rivers in the Waitaki Basin support particularly dense populations of banded dotterels. Maloney et al. (1997) showed that the largest population was the Tasman River (minimum count of 599 banded dotterel over three years), a river that reaches four kilometres wide in parts. The authors estimated the survey area to be 3,820 hectares in size (including water and vegetated areas), giving a minimum density of 0.16 banded dotterels per hectare. Wilson (2001) estimated the area of the lower Ngaruroro to be 3,501 hectares, giving a density of 0.31 banded dotterels per hectare (based on the data in Table 3), suggesting the Ngaruroro may support higher densities of banded dotterels (acknowledging different methods of analysis and different years of survey).
57 The reasons for the extraordinary size of the lower Ngaruroro banded dotterel population are worthy of investigation. It is likely to be the result of a combination of factors that could include: the availability of extensive breeding habitat, an extended breeding season in the north of New Zealand, different flood regimes (i.e. less floods during the breeding season), long term clearance of weeds using root raking leading to greater habitat availability and less cover for terrestrial predators, and abundant food sources such as invertebrates and fish.
58 In summary, the numbers of banded dotterel counted in 2018 (1,101 birds) may be one of the largest populations ever recorded on a river in New Zealand in recent years. Further, the population on the lower Ngaruroro represents more than 5% of the national population. These findings clearly demonstrate the outstanding bird habitats of the lower Ngaruroro for banded dotterel.
South Island pied oystercatcher (At Risk-Declining)
59 South Island pied oystercatcher (Haematopus finschi) is an endemic species that breeds in the South Island. Birds mostly breed on inland riverbeds or pasture, but
12000434 | 4075529 page 16
also nest in coastal areas, usually close to estuaries or lagoons. After breeding, South Island pied oystercatchers migrate to coastal areas throughout the North and South Islands. Population trends have changed markedly over the decades. The species was hunted by people until it was protected from shooting in 1940, at which point it probably numbered less than 10,000 birds. What happened next was described as a "spectacular irruption" of numbers. By 1970-71, the population numbered 49,000 birds, and by 1984-1993, it had further increased to 112,000 birds, estimated from national wader counts. However, it then appears to have declined back to 1980s levels, and is still considered to be in decline35.
60 The Ngaruroro River stands out in the North Island as being one of two locations where South Island pied oystercatcher have been recorded breeding since the 1980s. It is not known whether the second location, Lake Onoke, Wairarapa, is still used by pied oystercatchers. In contrast, the Ngaruroro supports a regular breeding population. The 2018 survey indicates that the population may have increased substantially from previous years (the species is a much larger bird than the banded dotterel, and counts will not be as adversely affected by a single observer undertaking surveys).
61 Clearly, the Ngaruroro River does not meet the 1% of 5% thresholds for this relatively numerous species. However, the river is very unusual in that it supports the only known population of breeding South Island pied oystercatcher in the North Island. In my opinion, this adds to the outstanding nature of the bird habitats of the lower Ngaruroro.
Black-fronted dotterel (At Risk-Naturally Uncommon)
62 Black-fronted dotterel (Elseyornis melanops) is a relatively recent coloniser from Australia. In Australia, it is widespread, normally inhabiting non-tidal freshwater wetlands, but often migrating to the coast during inland dry periods. A recent analysis of 30 years of Australian shorebird monitoring data indicates that the species is in decline around coastal Australia, thought to be due to degradation of wetlands in Australia's interior (in particular, lower water levels)36.
63 Black-fronted dotterel was first observed in New Zealand in 1954 at the Ahuriri Estuary in Napier. Several more sightings were recorded over the following years. In 1961, breeding was recorded for the first time a few years later with a total of 13 adults and nine juveniles observed on the Tutaekuri and Ngaruroro Rivers.
35 Sagar, P. & Veitch, D. 2014. Conservation assessment of the South Island oystercatcher Haematopus finschi. International Wader Studies 20: 155-160.
36 Clemens R., Rogers D.I., Hansen B.D., Gosbell K., Minton C.D., Straw P., Bamford M., Woehler E.J., Milton D.A., Weston M.A. and Venables B., 2016: Continental-scale decreases in shorebird populations in Australia. Emu-Austral Ornithology, 116: 119-135.
12000434 | 4075529 page 17
Hawke's Bay riverbeds were formally searched during the breeding season of 1962, and 109 birds were located37. Since then, the breeding distribution has extended to the southern North Island, north-east South Island, Canterbury, Otago and Southland38. The national population appears to be increasing slowly.
64 On the Ngaruroro, counts demonstrate the establishment of the black-fronted dotterel; 1962 – 39 birds, 1967 – 96 birds, 1972 – 134 birds, 1984 – 127 birds, 1985 – 145 birds. In November 2018, 217 birds were counted (200 were counted within the length of river surveyed in previous years). It is not clear whether this is an actual increase, or due to the more intensive survey method, or a combination of the two.
65 The population size as provided in the international Waterbird Population Estimates database is 1,700 birds39. Heather and Robertson (2005) describe the regional breakdown of this total as follows: Hawke's Bay 800, Wairarapa 300, Manawatu 300, Marlborough 50, Canterbury 150, Otago 50, and Southland 5040.
66 In comparison, a recent survey of 11 Wairarapa rivers recorded a total of 514 black-fronted dotterel, considerably more than the previous estimate of 300 birds in the Wairarapa. This suggests that the total population estimate of 1,700 birds may now be out of date. Most recently, Armitage states that the New Zealand population numbers fewer than 3,000 birds41. Using the estimate of 1,700 birds, the Ngaruroro population supports 11.8% of the national population. Using a maximum number of 3,000 birds, the river holds an estimated 6.7% of the national population.
67 The largest population of black-fronted dotterel in New Zealand may be on the Tukituki, where 368 birds were recorded in 1984 (c.f. 127-145 birds on the Ngaruroro at the same period), but there are no recent counts. Much more recently, the 2017 Wairarapa river surveys reported a population of 192 birds over 82 kilometres of the Ruamahanga River, suggesting this river also supports a nationally significant population. No other significant North Island populations were identified, though the lack of survey of the Rangitikei, one of the largest
37 Habraken T. 1996: Black-fronted dotterel breeding near Rotorua. New Zealand Wader Study Group. Newsletter 7: p5.
38 Gill B., Bell B.D., Chambers G.K., Medway D.G., Palma R.L., Scofield R.P., Tennyson A.J.D. and Worthy T.H. 2010: Checklist of the birds of New Zealand. Ornithological Society of New Zealand.
39 Wetlands International (2018). "Waterbird Population Estimates". Retrieved from wpe.wetlands.org on 27 Nov 2018.
40 Heather B. and Robertson H. 2005: The field guide to the birds of New Zealand. Revised Edition.
41 Armitage I. 2013 [updated 2017]: Black-fronted dotterel. In Miskelly C.M. (ed.) New Zealand Birds Online. www.nzbirdsonline.org.nz.
12000434 | 4075529 page 18
braided rivers in the North Island, is a significant information gap. Numbers of black-fronted dotterels in the South Island remain very low.
68 In summary, the lower Ngaruroro supports the largest known population of black- fronted dotterel in New Zealand, although it is likely that the Tukituki supports a greater number. Numbers exceed 5% of the national population, further demonstrating the outstanding bird habitats of the lower Ngaruroro.
Australasian bittern (Threatened-Nationally Critical)
69 Australasian bittern (Botaurus poiciloptilus) is one of New Zealand's rarest and most threatened bird species, recently upgraded to Nationally Critical. Australasian bittern is a wetland specialist, and its decline is most likely tied in to the massive loss of wetlands throughout New Zealand over the last century, but also possibly introduced predators. Recent research suggests winter starvation may be a significant issue facing the species42. The species is also found in Australia and New Caledonia, where it is equally threatened. The population size as provided in the international Waterbird Population Estimates database is 1,000-1,500 birds, with a 1% threshold of 10 birds (even lower in Australia)43. This is supported by the species' most recent threat classification which assumes the species to have a maximum population size of 1,000 mature individuals.
70 On the Ngaruroro River, bittern have been recorded several times from Pigsty Wetland, a tributary of the lower Ngaruroro, and are regularly observed at Waitangi Estuary, as well as other adjacent wetlands such as Lake Runanga. Tracking studies have shown that bittern use networks of wetlands many kilometres apart; birds using the Ngaruroro River are likely to also use other wetlands in the area. Stephenson undertook a helicopter survey of the river in 2009 and considered the river section between Whanawhana to Mangatahi to support considerable potential bittern habitat; he recorded an observation of a probable bittern in the river's riparian margins at Ohiti at much the same time.
71 An extraordinary photograph was taken by a local bird watcher of three Australasian bittern, a white heron (Nationally Critical; 1% threshold = 1 bird), and a white-faced heron (Not Threatened) at Waitangi Estuary in 201544.
42 Williams E. 2013 [updated 2018]: Australasian bittern. In Miskelly, C.M. (ed.) New Zealand Birds Online. www.nzbirdsonline.org.nz.
43 Wetlands International (2018). "Waterbird Population Estimates". Retrieved from wpe.wetlands.org on 27 Nov 2018.
44 The photograph can be found associated with this text: http://nzbirdsonline.org.nz/species/australasian- bittern.
12000434 | 4075529 page 19
72 John Cheyne, who has undertaken and assisted with bittern research in the North Island, including Hawke's Bay, has observed up to five bittern on a single occasion within the Horseshoe Wetland at the estuary, and considers the population in the Ngaruroro catchment to number 6-8 booming males, mostly on Lakes Runanga and Oingo on the northern side of the lower Ngaruroro (J. Cheyne pers. comm. December 2018).
73 It is possible that the wider wetland network of the lower Ngaruroro, combined with the lower Ngaruroro River itself and its estuary, support 10 or more bittern (the 1% threshold); few locations in New Zealand appear to support such numbers45. In my opinion, the presence of a breeding population of bittern in the wider Ngaruroro area that uses the lower river significantly raises the national importance of the Ngaruroro, whether or not it meets the 1% threshold. I strongly recommend that intensive survey of the river and adjacent wetlands is undertaken to better understand the population size and habitat use of bittern in the area, and to allow management actions to be determined to secure the population's survival in the region.
Pied stilt (Not Threatened)
74 Pied stilt (or black-winged stilt as it is known overseas) is found throughout much of the world. The New Zealand subspecies, Himantopus himantopus leucocephalus is also found in Australia and the Philippines. It is thought be a relatively recent arrival to New Zealand. The species was listed as At Risk- Declining in the 2012 iteration of threat classifications for birds46, but was downgraded to Not Threatened in 2017. The population was estimated at a minimum of 30,000 birds in 1996 using nationwide non-breeding counts47. The international Waterbird Population Estimates database still uses this estimate.
75 The 2018 survey on the lower Ngaruroro detected 559 pied stilt, or 1.9% of the national population, making the river nationally significant for this species.
76 In comparison, the 2017 surveys of the 11 Wairarapa rivers found a total of 317 pied stilt over all the rivers. In Canterbury, the maximum number recorded on the lower Rangitata over four surveys from 2000-2009 was 247; the maximum number recorded on the upper Rangitata over three surveys from 2008-2012 was 39; the maximum number recorded on the lower Rakaia over three surveys from
45 O'Donnell C.F.J. and Robertson H.A. 2016: Changes in the status and distribution of Australasian bittern (Botaurus poiciloptilus) in New Zealand, 1800s-2011. Notornis 63: 152-166.
46 Robertson, H.A.; Dowding, J.E.; Elliott, G.P.; Hitchmough, R.A.; Miskelly, C.M.; O'Donnell, C.F.J.; Powlesland, R.G.; Sagar, P.M.; Scofeld, R.P.; Taylor, G.A. 2013: Conservation status of New Zealand birds, 2012. New Zealand Threat Classification Series 4. Department of Conservation, Wellington. 22 p.
47 Sagar et al. 1999.
12000434 | 4075529 page 20
2006-2009 was 138; the maximum number recorded on the mid Rakaia from two surveys in 2011 and 2012 was 62 birds; and the maximum number recorded on the upper Rakaia over three consecutive surveys from 2011-2013 was six birds.
77 One Canterbury river with numbers of pied stilts comparable to the lower Ngaruroro is the Ashburton River. This river has the most continuous dataset for birds of any braided river, with almost annual counts since 1981. The first count in 1981 recorded 732 pied stilt compared to the Ngaruroro's 599 pied stilts. However, since then, the Ashburton has only recorded over 500 birds in 1982, 1984, and 1997 (data up to and including 2012), although it likely remains nationally important for the species.
78 In summary, the lower Ngaruroro has a nationally significant population of pied stilts that is likely to be one of the largest populations in the country.
Other habitats and bird species of the wider lower Ngaruroro area
79 In this section I will briefly describe avifauna values of habitats adjacent to the lower Ngaruroro mainstem that I consider ecologically significant, as birds using these areas may also use the lower river and its riparian margins.
(a) Black-billed gulls (Nationally Critical), discussed in paragraphs 41-48, also occasionally nest on the shingle bar at the estuary in significant numbers;
(b) Single white heron (Nationally Critical) are regular visitors to the estuary after breeding at Okarito. Extremely rare, numbering approximately 150- 200 birds, the regular presence of a single bird confers national significance to a site;
(c) Black-fronted tern (Nationally Endangered) overwinter at the Ngaruroro river mouth; estimated numbers are from 30 up to 75 individuals. The species threat classification indicates a maximum number of 5,000 mature individuals, suggesting 0.6-1.5% of the national population may be present outside of the breeding season;
(d) New Zealand dabchick (At Risk-Recovering) number 1,900-2,000 birds. Surveys of the population at wetlands around the lower Ngaruroro found 94 birds (4.7% of the national population). They have been recorded from Pigsty Wetland (no recent surveys), and are resident in Horseshoe Wetland at the estuary; and
(e) Blue duck pairs and single adults (Nationally Vulnerable) have been recorded in Big Hill Stream in the last two years, a tributary of the lower Ngaruroro. While these birds will not use the mainstem, their presence indicates high water quality in this tributary. The birds also comprise part of
12000434 | 4075529 page 21
the wider blue duck population in the upper catchment that I discussed in detail in my evidence for the Stage 1 Hearing.
The ecological significance of the lower Ngaruroro River for birds
80 The ecological significance of the lower Ngaruroro River for birds has been formally assessed twice, once by the former New Zealand Wildlife Service and, more recently, using the RiVAS. Ecologically important habitats of the Hawke's Bay region have been assessed as part of the national Protected Natural Areas Programme. The bird community of the river can also be evaluated against an internationally recognised set of criteria developed by as part of the Ramsar Convention which designates 'Wetlands of International Importance'.
81 I will discuss each of these assessments, and also summarise other key features of the Ngaruroro River bird community in the following section.
Sites of Special Wildlife Significance
82 The first assessment of ecological significance of the lower Ngaruroro River in relation to birds was reported in 1988 as part of the former New Zealand Wildlife Service's national inventory of SSWI48.
83 The Fauna Survey Unit of the New Zealand Wildlife Service surveyed the whole of New Zealand between 1977 and 1985 on a region by region basis to identify all 'Sites of Special Wildlife Interest'. All natural or semi-natural areas important as habitat for one or more species of wildlife were evaluated, and ranked according to a set of standard criteria. The five classifications were 'Outstanding', 'High', 'Moderate-High', 'Moderate', and 'Potential'. The data collected as part of the SSWI programme still continue to be widely used, although the classifications and criteria are not. The criteria for Outstanding and High wildlife values are set out in full below:
84 Outstanding:
(a) Presence of a breeding population of a highly endangered or rare endemic species;
(b) A population of an endemic species of very restricted distribution and which could become endangered;
(c) Areas essential to species from (a) and (b) for purposes other than breeding;
48 Parrish G.R. 1988: Wildlife and wildlife habitat of Hawke's Bay rivers. Science & Research Series 2. Department of Conservation, Wellington
12000434 | 4075529 page 22
(d) Areas of vital importance to internationally uncommon species (breeding and/or migratory);
(e) Areas of vital importance to internally migratory species with very limited distribution or abundance; and
(f) Largely unmodified ecosystem or example of original habitat type not represented elsewhere in the country, of large size and containing viable populations of all or almost all species which are typical of the ecosystem or habitat type.
85 High:
(a) Site containing an indigenous species which has declined significantly as a result of man's influence;
(b) One of few or the only breeding area for a non-endemic indigenous species of limited abundance;
(c) Habitat of an uncommon, discontinuously distributed species not adequately represented in a particular ecological region;
(d) Example of a largely unmodified site which is not represented to the same extent elsewhere in the ecological region and is used by most species which are typical of that habitat type for the region; and
(e) Presence of a species of an endemic family which is of limited abundance throughout the country although adequately represented in one ecological region but whose habitat is at some risk.
86 The Fauna Survey Unit completed surveys of four Hawke's Bay rivers – the Ngaruroro, Tukituki, Tutaekuri and Mohaka – as part of the national assessment. The ranking of the four rivers using the criteria for SSWI assessments also took into Ornithological Society of New Zealand survey data from 1962, 1967, 1972 (Ngaruroro, Tukituki, Tutaekuri), and 1984 (lower Mohaka).
87 The assessment concluded that the Ngaruroro River had 'High' wildlife values, and specifically highlighted the following in regard to the lower river:
(a) The Ngaruroro was the only river in the North Island with breeding South Island pied oystercatcher; and
(b) The Ngaruroro contained the greatest number of banded dotterel per kilometre of the four Hawke's Bay rivers surveyed.
12000434 | 4075529 page 23
88 The Fauna Survey Unit conducted their assessment of the Hawke's Bay rivers in 1988, when the threat status of many of New Zealand's indigenous birds was significantly different to the present day. Also, no rigorous nationally standardised system of threat classification had been established.
89 If the SSWI assessment was repeated today, it is possible that the Ngaruroro would be listed as Outstanding using SSWI criteria for the regular presence of breeding black-billed gulls and if confirmed, the presence of Australasian bittern.
River Values Assessment System
90 The ecological significance of bird populations of the lower Ngaruroro was formally assessed using the River Values Assessment System (or RiVAS) in 201249. The method is intended to provide a means to inform decision-makers of the significance of particular values of a river, using a consistent approach. Assessment methods for nine river values are in development or have been developed. One of the first sets of river values assessment criteria to be developed was for indigenous bird communities. The primary attributes of each river that are assessed for birds are:
(a) Relative distinctiveness (subjective; how widely is the habitat type or species assemblage distributed elsewhere in New Zealand);
(b) Amount of habitat (objective; measured in area for braided rivers and distance for single channel rivers);
(c) Numbers of birds (objective; adjusted by removing southern black-backed gulls from the total);
(d) Foraging guilds (objective; ranges from 0 to 8 foraging guilds);
(e) Number of Threatened or At Risk bird species present (objective; note grey duck and Australasian bittern are not included); and
(f) Proportion of Threatened or At Risk bird species present with a significant proportion of their total populations (i.e. >1% or >5%; objective or subjective).
91 These six attributes are then each given a score, which is then summed. In the case of the Hawke's Bay assessment, the summary scores are then ranked. Rivers where a species exceeds 5% of the national population are immediately
49 Hughey K.F.D., Cameron F., Cheyne J., Dickson R., Forbes A., Hashiba K., Rook H., Sharp T., Stephenson B. and Welch B. 2012: Native birdlife in Hawke's Bay: Application of the River Values Assessment System (RiVAS and RiVAS+). Lincoln University, New Zealand.
12000434 | 4075529 page 24
considered nationally significant, regardless of score, "as this level has been used in a number of Water Conservation Order decisions as being a threshold for national importance (despite the fact that the World Conservation Union (IUCN) uses a 1% level for international significance)". National significance is also given to those rivers that have a total score of 15 or more.
92 The assessment split the Ngaruroro into the upper river and lower river (at the Whanawhana cableway). The lower river scored '12' and ranked second in the Hawke's Bay behind the lower Tukituki (which was the only river given national significance as it was considered to support >5% of the national banded dotterel population).
93 However, threat classifications have changed since the RiVAS assessment was undertaken, and recent survey data from the lower Ngaruroro is now available.
94 The 2018 survey data indicate that the lower Ngaruroro supports approximately 5.6% of the national population of the Nationally Vulnerable banded dotterel (using the more recent estimate of a maximum of 20,000 mature individuals; paragraphs 50-53). The survey data also indicate that the lower Ngaruroro supports approximately 11.8% of the national population of the Nationally Uncommon black-fronted dotterel, using the estimate of 1,700 birds, or 6.7% of the national population using the estimate of a maximum number of 3,000 birds (paragraphs 65-66).
95 Either one of these findings means that the lower river can be automatically assigned national significance, regardless of the summed score.
Protected Natural Areas Programme
96 The survey of the Heretaunga Ecological District for the Protected Natural Areas Programme identified the section of the Ngaruroro River between the gorge at Whanawhana to the Fernhill Bridge as a Recommended Area for Protection (or RAP)50. The justification for this RAP was provided as follows: "The best and largest example of a braided river system in Hawke's Bay, the Ngaruroro River has high landscape and wildlife values. Large areas of relatively undisturbed habitat are available to a range of birds, the most significant being black-fronted terns and banded dotterels".
Wetlands of International Significance (the Ramsar Convention)
97 The Ramsar Convention was established to encourage nations to work towards the conservation and wise use of the world's wetlands. The treaty was negotiated
50 Lee A.C. 1994: Heretaunga Ecological District: Survey for the Protected Natural Areas Programme. Department of Conservation. 140p.
12000434 | 4075529 page 25
during the 1960s, and adopted in the Iranian city of Ramsar in 1971. Contracting Parties, of which New Zealand is one (becoming a party to the Convention in 1976), commit to work towards the wise use of all their wetlands, and to designate suitable wetlands for the list of Wetlands of International Importance (the "Ramsar List") and ensure their effective management.
98 As of the end of 2016, 169 countries were contracting parties51. As of 8 June 2015, 2,208 Ramsar sites covering 210 million hectares have been listed52. Within New Zealand, six sites have been listed to date; Whangamarino, Waikato; Kopuatai Peat Dome, Waikato; Firth of Thames, Waikato; Manawatu River Estuary, Manawatu; Farewell Spit, Nelson; and Awarua Wetland/Waituna Lagoon, Southland. Other sites are likely to be added in the future53. Potential candidates for the Ramsar Convention's list of Wetlands of International Importance are assessed against eight criteria. Several criteria are relevant to bird populations, and are listed below:
(a) Criterion 2: A wetland should be considered internationally important if it supports vulnerable, endangered, or critically endangered species or threatened ecological communities;
(b) Criterion 3: A wetland should be considered internationally important if it supports populations of plant and/or animal species important for maintaining the biological diversity of a particular biogeographic region;
(c) Criterion 4: A wetland should be considered internationally important if it supports plant and/or animal species at a critical stage in their life cycles, or provides refuge during adverse conditions;
(d) Criterion 5: A wetland should be considered internationally important if it regularly supports 20,000 or more water birds; and
(e) Criterion 6: A wetland should be considered internationally important if it regularly supports 1 percent of the individuals in a population of one species or subspecies of water bird.
99 Evaluation using Ramsar criteria is an internationally recognised method to assess the biodiversity values of wetlands across the globe. The criteria provide a consistent and robust method for assessing the international importance of
51 http://www.ramsar.org/sites/default/files/documents/library/annotated_contracting_parties_list_e.pdf
52 The Ramsar Convention 2015: The 4th Strategic Plan 2016-2024. Adopted by the 12th Meeting of the Conference of the Parties at Punta del Este, Uruguay, 1-9 June 2015.
53 I co-authored a management plan in June for the Avon-Heathcote Estuary/Ihutai for a Trust that intends to use the plan to seek Ramsar status for the Christchurch estuary and oxidation ponds.
12000434 | 4075529 page 26
wetlands including rivers. In my opinion, it is more appropriate to assess the Ngaruroro river as a whole against the Ramsar criteria, most importantly because each of the main habitat types within the river – the upper forested channels, the lower braids, and the estuary – each have unique and nationally significant bird values. Considered together and assessed against the Ramsar criteria, these combined values demonstrate the overall importance of the river to birds much more accurately than considering each of the main habitat types separately.
100 The Department of Conservation has published national guidelines for the assessment of potentially internationally significant wetlands in New Zealand54, and I have used this guide to assess how well the criteria are met in regard to the upper catchment. The guidelines use the following terminology for each criterion: 'Strongly', 'Moderately', and 'Slightly' met.
101 The guidelines state that Criterion 2 is strongly met if the wetland is "Natural or near-natural habitat for a population of one or more species that are Nationally Critical or Nationally Endangered", and moderately met if the wetland is "Natural or near-natural habitat for one or more species that are Nationally Vulnerable".
102 Interestingly, the Department of Conservation guidelines use the New Zealand threat classification categories of Nationally Critical, Nationally Endangered, and Nationally Vulnerable, rather than the international IUCN Red List categories Critically Endangered, Endangered, and Vulnerable, which would normally be used for a Ramsar assessment. The authors state that this is because for some taxon groups, such as invertebrates, the international classifications can be significantly out-of-date.
103 The only regular resident of the lower Ngaruroro considered internationally threatened is the black-billed gull, listed as Endangered. Australasian bittern is also listed as Endangered, and if regularly present at Pigsty Swamp and/or elsewhere on the lower Ngaruroro (like the riparian margins), would also trigger this criterion. Both these species are considered Nationally Critical, and therefore 'strongly' meet the criterion according to Department of Conservation guidelines. The presence of a large banded dotterel population 'moderately' meets Criterion 2.
104 The guidelines state that Criterion 4 is strongly met by "Wetlands that are demonstrated to be key habitats and national strongholds for threatened indigenous wetland-dependent species during breeding, migration, moulting or weather extremes". The lower Ngaruroro is clearly a national stronghold for banded dotterel (Nationally Vulnerable), given it may support one of the largest
54 Denyer K. and Robertson H. 2016: National guidelines for the assessment of potential Ramsar wetlands in New Zealand. Department of Conservation, Wellington. 58 p.
12000434 | 4075529 page 27
known populations of the species in New Zealand. The guidelines state that the criterion is moderately met by "unusually high concentrations" of At Risk species; this would apply to the lower Ngaruroro for black-fronted dotterel.
105 Criterion 5 – a wetland that supports more than 20,000 birds – is not met. The 2018 survey of the Ngaruroro River (excluding the estuary) observed just over 5,000 individual birds.
106 Criterion 6 identifies wetlands that regularly support 1% or more of a waterbird population. This is clearly met for banded dotterel, black-fronted dotterel, and pied stilt. According to the Department of Conservation guidelines, Criterion 6 is 'moderately' met by a wetland that "Regularly supports 2-24% of a biogeographical population of one of more waterbird species or subspecies", and is therefore triggered by both banded dotterel and black-fronted dotterel.
107 In summary, I consider that the lower Ngaruroro meets three Ramsar criteria that define a wetland of international significance, and that Criteria 2 and 4 are strongly met due to the regular presence of black-billed gull, and the presence of one of largest banded dotterel populations in New Zealand.
Comparison with other braided rivers protected by Water Conservation Orders
108 Thirteen rivers are protected by Water Conservation Orders. Eight of these were found to have braided reaches by Wilson (2001), although several, such as the Motu and Mohaka rivers, only contain very small areas of braided habitat. Three of the rivers, the Rakaia, Ahuriri and Rangitata in Canterbury, are classical, wide braided rivers. Two lesser known braided rivers are the Oreti and Mataura in Southland.
109 The Rakaia was the first of New Zealand's braided rivers to receive a Water Conservation Order in 1988. The initial Tribunal decision found that the river provided outstanding wildlife habitat. Specifically, in regard to birds, the Tribunal considered that the river supported outstanding wrybill habitat. The application highlighted the high diversity of water dependant birds, the abundance of those birds, the large area of braided habitat, and that the river was the most important breeding area for wrybill.
110 The Ahuriri received a Water Conservation Order in 1990. The committee report (1984) considered that the river supported outstanding wildlife habitat, with significant numbers of wrybill, black-fronted tern, and black-billed gull, but particularly black stilt, which, at the time, was estimated to number 12 pairs. The report noted that there were a number of other similarly unmodified braided river habitats, both within the region and outside of the region, and that no claim was being made that the Ahuriri was necessarily the best example.
12000434 | 4075529 page 28
111 The Rangitikei was granted a Water Conservation Order in 1993, in part because of outstanding wildlife habitat. However, it appears from the application documents available that this was largely in consideration of the presence of blue duck. However, it is one of the largest braided rivers in the North Island, but appears to have had no recent bird surveys (as I have noted earlier). I could not find any further information.
112 The Mataura River, Southland, was granted a Water Conservation Order in 1997, singularly on the basis of its outstanding brown trout fishery. In my opinion, the Mataura River is one of the most important in New Zealand for the Nationally Critical black-billed gull.
113 Both the upper Rangitata and the lower Rangitata were found to be outstanding bird habitat for waterbird species, particularly braided river specialists.
114 In comparison, the lower Ngaruroro supports one of the largest known populations of banded dotterel, black-fronted dotterel, and pied stilt in New Zealand. Like the Rakaia and Rangitata, it has a diverse waterbird population, including the frequent presence of black-billed gull colonies (rare in the North Island), and the only known river-breeding population of South Island pied oystercatcher in the North Island.
115 In my opinion, it is clear that the lower Ngaruroro is comparable to rivers such as the Rakaia, Rangitata, and Ahuriri, in that it supports highly significant populations of braided river birds in a national and international context.
The potential effects of human-related factors on the Ngaruroro bird community
116 In 2016, a guiding document on "Management and research priorities for conserving biodiversity on New Zealand's braided rivers" was published by the Department of Conservation55. In it, the document lists human-related factors that threaten braided rivers. I have reproduced those factors that relate specifically to birds and their food sources below:
(a) Predation and disturbance by introduced mammalian predators and native avian predators (numbers of the latter appear to be high as a result of recent land use changes);
(b) Invasive terrestrial and aquatic species, which threaten habitat integrity and food webs, and displace species;
55 O'Donnell C.F.J., Sanders M., Woolmore C. and Maloney R.F. 2016: Management and research priorities for conserving biodiversity on New Zealand's braided rivers. Department of Conservation, Wellington, New Zealand. 46 p.
12000434 | 4075529 page 29
(c) Altered flow regimes and creation of impoundments which change flow patterns and, in some cases, destroy preferred habitats and threaten food availability;
(d) Water abstraction (leads to increased dewatering affecting instream habitat as well as groundwater, floodplain springs and wetlands);
(e) River control works (stop banks, willow planting, channelisation, bridge abutments, gravel extraction) that channel, stabilise and modify habitats;
(f) Recreational activities (e.g. 4WD vehicle use, fishing, dog walking), which disturb or kill wildlife and reduce habitat quality; and
(g) Water quality – elevated nutrient levels from increased nutrient inputs from surrounding catchments causing excessive algal growths, which can alter aquatic invertebrate and fish communities. Under certain conditions, algal species that produce toxins may dominate, affecting recreational use of waterways.
117 In my opinion, the list should have also included intentional harm by people. During the period of my doctoral research on the Nationally Critical black-billed gull on Southland rivers, a vehicle was driven through two of my monitored colonies and illegal shooting of adult gulls occurred at two non-monitored colonies. At the latter, approximately 90 adults in total were shot. Children throwing rocks killed a banded bird at another non-monitored colony and probably damaged nests at another. Previous to my work in Southland, a man had been convicted for driving a vehicle through a black-billed gull colony.
118 More recently, in January 2008, several hundred black-billed gull adults and chicks were shot in a large Canterbury colony, a loss of more than half of the birds present; a man was jailed in 2013 for driving his vehicle through a colony of c.3,000 black-billed gulls on the Ashburton River, killing chicks and squashing eggs; a colony in the same location had been attacked in 2007, causing the deaths of more than 100 birds; another man was convicted of shooting a black- billed gull in a colony in Southland in 2015; a Canterbury ornithologist found 50 dead black-billed gull chicks that had been stoned to death on the Ashley River also in 2015; and a black-billed gull was found alive with an arrow through its body in Timaru, in 2017.
119 The Ngaruroro is not immune. A colony at Waitangi Estuary numbered 500 birds on 29 October 1981, and was visited weekly to check progress. A total of 230
12000434 | 4075529 page 30
nests was eventually counted. However, on the 21 November, the site had been vandalised and the colony had been deserted56.
120 In contrast to noisy black-billed gull colonies, solitary nesting species such as banded dotterel, whose nests are highly cryptic, are less likely to be the target of intentional damage, but are at much greater risk of being accidental destroyed by the likes of recreational 4x4 use on riverbeds such as the Ngaruroro. Drivers and their passengers may observe the disturbed adults in flight, but could be entirely oblivious to the presence of nests.
121 The effects of introduced predators such as cats and mustelids are considered to be the leading cause of decline of all of New Zealand's Threatened and At Risk bird species characteristic of braided rivers, such as black stilt, black-billed gull, banded dotterel, wrybill, and South Island pied oystercatcher. The effects of introduced predators can be exacerbated by the reduction of flows in braided rivers. Table 4, from 'Management and research priorities for New Zealand's braided rivers', shows the complex interplay of potential effects leading from reduced flows in braided rivers.
Table 4: Potential effects and consequences of reduced flow on braided river flora and fauna during the breeding season (taken from O'Donnell et al. 2016)
Prediction Potential Effects Potential Consequences Lower flows Lower food availability Greater competition for food Increased weed encroachment Less breeding and feeding habitat Less food-producing habitat Increased vulnerability of nests to flooding Increased access to islands by Increased cover for mammalian mammalian predators predators and their prey Lower productivity and survival Fewer channels or Reduced area of feeding habitat Fewer habitat choices – greater braids competition for food Increased access to islands by Less-optimal breeding habitat mammalian predators Lower productivity and survival Fewer islands Fewer islands safe from Lower productivity and survival predators Increased channel Reduced accessibility to Less breeding and feeding stability preferred foods habitat Increased weed encroachment Increased cover for mammalian predators
56 Booth D.F. (compiler) 1983: Classified summarised notes. Notornis 30: 34-68.
12000434 | 4075529 page 31
122 My PhD research on black-billed gulls in Southland during 2004-2006 was one of the first studies to provide strong evidence for increased productivity of birds nesting on islands within rivers versus birds nesting on river banks. I considered that this was most likely due to terrestrial predators such as cats, ferrets and stoats being less inclined to cross water channels to access colonies.
123 Subsequent research has further investigated and developed this hypothesis. Dr Georgina Pickerell assessed productivity of multiple bird species on islands and riverbanks of six South Island rivers, and predator presence and visitation frequency at 18 riverbank sites and 58 island sites on the Rangitata River57. She found a tendency for islands to have higher productivity, but did not assess the influence of avian predators such as black-backed gulls on productivity, which may have affected the strength of relationship, as the large gull is known to prey on braided river bird nests. She also found fewer species of mammalian predators on islands, with a 36% of islands recording no presence. Further, she found that predator presence on river islands was associated with island size, presence of vegetation and rabbits/hares, and distance to the mainland.
124 Dr Ann-Kathrin Schlesselmann investigated the effects of clearing vegetated islands on the Waitaki River on the breeding of black-fronted tern58. She recorded seven species of mammalian predators, but detected fewer species and far fewer occurrences of those species on islands compared to riverbanks, and even fewer mammalian predators on cleared islands compared to vegetated ones – for example, no mustelids were detected on cleared islands. However, more than half of monitored nests failed during the incubation phase, mostly due to black- backed gull predation, irrespective of the presence of vegetation on the island.
125 Another study demonstrated that declines of black-fronted tern (Nationally Endangered), a braided river species that breeds on South Island rivers, were greatest on rivers that had significantly reduced flows59.
126 Flows can be reduced by hydroelectric dams. For example, the dam system on the Waitaki River, Canterbury, reduced the braided width of the river from approximately two kilometres before construction in 1935, to approximately 0.5
57 Pickerell G. 2015: Braided-river islands as refuges from introduced mammalian predators: characteristics influencing predator presence, and consequences of reduced flow. PhD thesis, University of Otago. 271 pp.
58 Schlesselmann A.K.V., O'Donnell C.F., Monks J.M. and Robertson B.C. 2018: Clearing islands as refugia for black-fronted tern (Chlidonias albostriatus) breeding colonies in braided rivers. New Zealand Journal of Ecology 42: 0-0.
59 O'Donnell C.F. and Hoare J.M. 2011: Meta-analysis of status and trends in breeding populations of black- fronted terns (Chlidonias albostriatus) 1962-2008. New Zealand Journal of Ecology 35: 30-43.
12000434 | 4075529 page 32
kilometres today60. Water abstraction for various purposes also reduces flows, which has the potential to stabilise islands, increase channelisation, increase weed invasion, reduce channel numbers causing loss of island habitat, improve access for terrestrial predators, and provide those predators with cover, and food for their other prey, such as lagomorphs and rodents.
127 In order to maintain the existing condition of the outstanding bird habitat of the lower Ngaruroro from the impacts of management practices that have the potential to significantly affect nationally important bird populations, it will be important that the draft Water Conservation Order provisions prevent water impoundment, and maintain braided river character and flow variability.
The lower Ngaruroro as outstanding habitat for birds
128 To summarise, I consider that the lower Ngaruroro River provides outstanding habitat for braided river birds for numerous reasons. These are:
(a) The lower Ngaruroro River is the second largest braided river in the North Island. Braided river systems are an historically rare ecosystem in New Zealand, and rare internationally. The extent of braided river systems in the North Island is extremely limited compared to the South Island;
(b) The lower Ngaruroro provides a variety of habitats that are used by a diverse range of bird species for breeding and feeding;
(c) The lower Ngaruroro River is one of few rivers in the North Island that regularly support sizeable colonies of the black-billed gull (Nationally Critical), a species that is rare in the North Island;
(d) The lower Ngaruroro River supports one of the largest known populations of banded dotterel (Nationally Vulnerable), black-fronted dotterel (At Risk- Naturally Uncommon), and pied stilt (Not Threatened) in New Zealand. Two of these populations exceed the 5% threshold; and
(e) The lower Ngaruroro River comprises part of a network of wetlands in the lower Ngaruroro area that may support a population of Australasian bittern (Nationally Critical) that exceeds the 1% threshold.
Rachel Katherine McClellan 12 December 2018
60 Hicks D.M., Duncan M.J., Lane S.N., Tal M. and Westaway R. 2007: 21 Contemporary morphological change in braided gravel-bed rivers: new developments from field and laboratory studies, with particular reference to the influence of riparian vegetation. Developments in Earth Surface Processes 11: 557-584.
12000434 | 4075529 page 33
Appendix 1: Bird species recorded in the Ngaruroro Catchment (from Stephenson 2010; Seaton 2013, Birds New Zealand unpublished data)
Common Name Species Name Threat Classification Presence Location (Robertson et al. 2017)61 Australasian bittern Botaurus poiciloptilus Nationally Critical Rare, resident Estuary, wetlands Black-billed gull Larus bulleri Nationally Critical Uncommon, regular Estuary, lower river Grey duck Anas superciliosa Nationally Critical Rare (no longer present?) Estuary, river New Zealand shore plover Thinornis novaeseelandiae Nationally Critical Rare, infrequent Estuary White heron Ardea modesta Nationally Critical Rare, infrequent Estuary, lower river Black-fronted tern Chlidonias albostriatus Nationally Endangered Common, regular Estuary Reef heron Egretta sacra sacra Nationally Endangered Rare, infrequent Estuary Banded dotterel Charadrius bicinctus bicinctus Nationally Vulnerable Abundant, regular Estuary, river Blue duck Hymenolaimus malachorhynchos Nationally Vulnerable Uncommon, resident River Caspian tern Hydroprogne caspia Nationally Vulnerable Uncommon, regular Estuary Lesser knot Calidris canutus rogersi Nationally Vulnerable Rare, infrequent Estuary Wrybill Anarhynchus frontalis Nationally Vulnerable Rare, infrequent Estuary, lower river Banded rail Gallirallus philippensis assimilis At Risk-Declining Rare, unknown Wetland Eastern bar-tailed godwit Limosa lapponica baueri At Risk-Declining Rare, infrequent Estuary Marsh crake Porzana pusilla affinis At Risk-Declining Rare, regular Estuary New Zealand pipit Anthus novaeseelandiae novaeseelandiae At Risk-Declining Common, regular Estuary, river North Island fernbird Bowdleria punctata vealeae At Risk-Declining Uncommon, resident Estuary, wetlands Red-billed gull Larus novaehollandiae scopulinus At Risk-Declining Common, regular Estuary Spotless crake Porzana tabuensis tabuensis At Risk-Declining Rare, regular Estuary, wetlands South Island pied oystercatcher Haematopus finschi At Risk-Declining Uncommon, regular Estuary, lower river White-fronted tern Sterna striata striata At Risk-Declining Abundant, regular Estuary New Zealand dabchick Poliocephalus rufopectus At Risk-Recovering Uncommon, regular Estuary Northern New Zealand dotterel Charadrius obscurus aquilonius At Risk-Recovering Rare, infrequent Estuary, wetlands Variable oystercatcher Haematopus unicolor At Risk-Recovering Rare, regular? Estuary Black-fronted dotterel Elseyornis melanops At Risk-Naturally Uncommon Abundant Estuary, lower river Black shag Phalacrocorax carbo novaehollandiae At Risk-Naturally Uncommon Uncommon, regular Estuary, river Little black shag Phalacrocorax sulcirostris At Risk-Naturally Uncommon Uncommon, regular Estuary, river Royal spoonbill Platalea regia At Risk-Naturally Uncommon Rare, infrequent Estuary Australasian gannet Morus serrator Not Threatened Uncommon, regular Estuary Australasian shoveler Anas rhynchotis Not Threatened Uncommon, infrequent Estuary, river Black swan Cygnus atratus Not Threatened Rare, infrequent Estuary
61 Common names, species names, and classifications from Robertson H.A., Baird K., Dowding J.E., Elliott G.P., Hitchmough R.A., Miskelly C.M., McArthur N., O'Donnell C.F.J., Sagar P.M., Scofield R.P. and Taylor G.A. 2017: Conservation status of New Zealand birds, 2016. New Zealand Threat Classification Series 19. Department of Conservation, Wellington. 23 p.
12000434 | 4075529 page 34
Common Name Species Name Threat Classification Presence Location (Robertson et al. 2017)61 Grey teal Anas gracilis Not Threatened Rare, infrequent Estuary, river Little shag Phalacrocorax melanoleucos brevirostris Not Threatened Rare, infrequent Estuary New Zealand kingfisher Todiramphus sanctus vagans Not Threatened Common, regular Estuary, river Paradise shelduck Tadorna variegata Not Threatened Abundant Estuary, river Pied stilt Himantopus himantopus leucocephalus Not Threatened Abundant Estuary, lower river Pukeko Porphyrio melanotus melanotus Not Threatened Common, regular Estuary, lower river Southern black-backed gull Larus dominicanus dominicanus Not Threatened Abundant Estuary, lower river Spotted shag Stictocarbo punctatus punctatus Not Threatened Rare, infrequent Estuary Spur-winged plover Vanellus miles novaehollandiae Not Threatened Abundant, resident Estuary, river White-faced heron Egretta novaehollandiae Not Threatened Uncommon, resident Estuary, river Arctic skua Stercorarius parasiticus Migrant Rare, infrequent Estuary Curlew sandpiper Calidris ferruginea Vagrant Rare, infrequent Estuary Eastern cattle egret Ardea ibis coromanda Migrant Rare, infrequent Estuary Eastern little tern Sternula albifrons sinensis Migrant Rare, infrequent Estuary Gull-billed tern Gelochelidon nilotica Vagrant Rare, infrequent Estuary Pacific golden plover Pluvialis fulva Migrant Rare, infrequent Estuary Red-necked stint Calidris ruficollis Migrant Rare, infrequent Estuary Sharp-tailed sandpiper Calidris acuminata Migrant Rare, infrequent Estuary Siberian tattler Tringa brevipes Migrant Rare, infrequent Estuary Terek sandpiper Tringa cinerea Migrant Rare, infrequent Estuary Turnstone Arenaria interpres Migrant Rare, infrequent Estuary White-winged black tern Chlidonias leucopterus Migrant Rare, infrequent Estuary Intermediate egret Ardea intermedia Vagrant Rare, infrequent Estuary Little egret Egretta garzetta immaculata Vagrant Rare, infrequent Estuary Pectoral sandpiper Calidris melanotos Vagrant Rare, infrequent Estuary Canada goose Branta canadensis Introduced and Naturalised Uncommon, infrequent River Mallard Anas platyrhynchos Introduced and Naturalised Common Estuary, river North Island brown kiwi Apteryx mantelli At Risk-Declining Terrestrial North Island rifleman Acanthisitta chloris granti At Risk-Declining Terrestrial North Island robin Petroica longipes At Risk-Declining Terrestrial Whitehead Mohoua albicilla At Risk-Declining Terrestrial Red-crowned parakeet Cyanoramphus novaezelandiae novaezelandiae At Risk-Relict Terrestrial Long-tailed cuckoo Eudynamys taitensis At Risk-Uncommon Terrestrial Bush falcon Falco novaeseelandiae ferox At Risk-Recovering Terrestrial, river North Island kaka Nestor meridionalis septentrionalis At Risk-Recovering Terrestrial Bellbird Anthornis melanura Not Threatened Terrestrial Grey warbler Gerygone igata Not Threatened Terrestrial Kereru Hemiphaga novaeseelandiae Not Threatened Terrestrial
12000434 | 4075529 page 35
Common Name Species Name Threat Classification Presence Location (Robertson et al. 2017)61 Morepork Ninox novaeseelandiae novaeseelandiae Not Threatened Terrestrial North Island fantail Rhipidura fuliginosa placablis Not Threatened Terrestrial Pied tomtit Petroica macrocephala toitoi Not Threatened Terrestrial Shining cuckoo Chrysococcyx lucidus lucidus Not Threatened Terrestrial Silvereye Zosterops lateralis lateralis Not Threatened Terrestrial Swamp harrier Circus approximans Not Threatened Terrestrial, river Tui Prosthemadera novaeseelandiae novaeseelandiae Not Threatened Terrestrial Welcome swallow Hirundo neoxena neoxena Not Threatened Terrestrial, river Yellow-crowned parakeet Cyanoramphus auriceps Not Threatened Terrestrial Australian magpie Gymnorhina tibicen Introduced and naturalised Terrestrial California quail Coturnix novaezelandiae Introduced and naturalised Terrestrial Chaffinch Fringilla coelebs Introduced and naturalised Terrestrial Common blackbird Turdus merula Introduced and naturalised Terrestrial Common myna Acridotheres tristis Introduced and naturalised Terrestrial Common pheasant Phasianus colchicus Introduced and naturalised Terrestrial Common redpoll Carduelis flammea Introduced and naturalised Terrestrial Common starling Sturnus vulgaris Introduced and naturalised Terrestrial Hedge sparrow Prunella modularis Introduced and naturalised Terrestrial European goldfinch Carduelis carduelis Introduced and naturalised Terrestrial European greenfinch Carduelis chloris Introduced and naturalised Terrestrial Feral or greylag goose Anser anser Introduced and naturalised Terrestrial House sparrow Passer domesticus Introduced and naturalised Terrestrial Rock or feral pigeon Columba livia Introduced and naturalised Terrestrial Rook Corvus frugilegus Introduced and naturalised Terrestrial Skylark Alauda arvensis Introduced and naturalised Terrestrial Song thrush Turdus philomelos Introduced and naturalised Terrestrial Yellowhammer Emberiza citrinella Introduced and naturalised Terrestrial
12000434 | 4075529 page 36