West Coast Marine and Coastal Localities:
a Detailed Description of 14 Segments
5.4 Buller Bay
(Mokihinui River mouth – ‘Penguin Beach’, 56 km)
From the northern end of the Buller Bay segment south to about Waimangaroa, the coastal hills and the escarpments of the Denniston and Stockton Plateaux reach close to the coastline, save for a narrow coastal plain. Further south the coastal plain broadens significantly to form the northern margins of the Foulwind Plain. Coastal land in this segment is mostly modified by settlements, farming and other land development, especially on the coastal flats and the Cape Foulwind headland; natural vegetation cover is retained on many coastal hillsides.
The Mokihinui and Buller Rivers, as well as a number of smaller rivers and streams, flow out to sea and some are associated with coastal wetlands. The seabed is mostly of a uniform shelf grading out to fine sediments, but with inshore rocky reefs in some places and a variety of beach types. The area supports marine life that is typical of such habitats in the northern West Coast. Access to and use of this coastal/marine segment is widespread; it is one of the more densely populated parts of the West Coast. Dairy farming and residential development are predominant land uses, especially on the coastal sand plain.
Notable features of this segment include: its higher resident population, its accessibility from Westport, SH 67 and other roads, Westport Harbour, remnant coastal sandplain wetlands and forests, coastal wildlife, natural landscapes and protected catchments, diverse marine habitats, cultural and historic heritage, and recreational uses.
Existing protection includes: areas of conservation land associated with coastal wetlands and other parts of the Foulwind sand plain and more extensive protected areas in the coastal and inland hill country. There are also several areas closed to whitebaiting and specified areas under the Regional Coastal Plan.
5.3.2 Natural Features
Coastal Land and Islands
Most of the hillslopes in the north of this segment are forested. In contrast coastal sand plain forest remnants are small. Johnson (1992) rated the coastal and beach vegetation from Granity to Jones Creek as significant, particularly noting the persistence of matai/totara forest on ancient beach ridges. The cobble beaches in this area are suitable habitat for native skinks, with several sightings reported 66.
The Cape Foulwind area and Tauranga Bay with Okari Lagoon and the Charleston Coast further to the south.
Coastal erosion is a problem in some places; for instance, erosion at Carters Beach is currently of major concern as it may threaten the Westport airfield. In contrast, from about Orowaiti to Carters Beach, the construction of harbour training works at the Buller River mouth since 1870 has resulted in the beach building out seawards by up to a kilometre or more. This new land has been developed into residential areas of Westport township, harbour facilities and recreational areas; these construction works have also formed new tidal wetlands and caused an eastward migration of the Orowaiti River mouth.
|Westport and the Buller River mouth area
Photo: T Hume, NIWA
|Orowaiti Lagoon mouth and North Beach
Photo: T Hume, NIWA
Cape Foulwind, the granite and limestone headland at the northwest corner
of the Foulwind Plain, is a distinctive coastal feature of the Buller Bay
segment. The headland’s landscape has been altered by land development
over the years but regeneration of native vegetation is being enhanced in
some areas by active planting and exclusion of grazing stock.
Wall Island is one of the largest island habitats in the northern West Coast and along with the immediately adjoining headland of Tauranga Bay, it supports the threatened seal cress67 and breeding sites for NZ fur seals and burrowing seabirds (fairy prions and muttonbirds). The Three Steeples and associated rock stacks are prominent coastal landmarks lying off Cape Foulwind. The three main islets are topped by a sparse cover of taupata; their cliffs above high tide level are bare rock.
Sites of geological interest include: the sedimentary geology, igneous geology and marine terrace and tombolo landforms around Cape Foulwind and Tauranga Bay and the igneous geology of Torea Rocks68.
Coastal Wetlands and Waterways
The largest waterways are the Buller and Mokihinui Rivers, with estimated annual suspended sediment discharges of 2.7 and 0.29 million tonnes respectively69. Smaller rivers discharging to sea include the Ngakawau, Waimangaroa, Whareatea and Orowaiti.
Orowaiti Lagoon is the largest tidal wetland in the Buller Bay segment. It contains a variety of estuarine habitats including saltmarsh, mudflats, sand flats and channels. However, the lagoon is seriously polluted by sewage and farm waste that pose a human health risk to the lagoon’s shellfish beds. Buller River mouth tidal wetlands are outside the coastal marine area but include Bradshaw’s Creek and areas locally known as ‘Lost Lagoon’ and ‘the Floating Basin’. These wetlands in combination provide an extensive area of natural habitat for aquatic plants (e.g. saltmarsh herbs and rushes), birds (e.g. bitterns, crakes, waterfowl) and fish (e.g. giant kokopu, inanga).
Birchfield swamp and other coastal wetlands lie mostly outside the coastal marine area, but are typically associated with river mouths and add to the diversity of aquatic habitats in the area.
Seashore and Marine Areas
The Buller Bay segment contains a wide variety of seashore types.
Beaches north of about Waimangaroa have a steep intertidal cobble beach ridge dropping down to a flat sandy base extending beyond the low tide level. These are the most extensive mobile cobble beach system on the West Coast. While they support very little intertidal marine life, they mostly remain in an unmodified state. Between Waimangaroa and Fairdown the cobble beaches begin to grade into the pure sand beaches that are a feature of the shoreline from Westport to Cape Foulwind.
North Beach, Carters Beach and Okari Beach are the most extensive pure sand beach system along the West Coast. They appear to support one of the richest sand beach faunas in the region, including surf clams (e.g. Dosinia, Spisula, Mactra and Tellina), paddle crabs and coastal fish species.70
|Granity township is positioned along a
cobble ridge beach.
Photo: T Hume, NIWA
|The Ngakawau River, with Hector to the North (left) and Ngakawau to the South.
Photo: T Hume, NIWA
The physical dynamics of the Buller River mouth has been extensively studied
because of its commercial relevance to harbour operations71.
The coastal geomorphology of other parts of Buller Bay has been studied
mainly in relation to coastal hazards and resource consent proposals72.
Rocky reefs are a prominent feature of the Cape Foulwind and Three Steeples area, and patchy reefs also occur in intertidal and shallow waters in the vicinity of Nikau and Granity. The Three Steeples area includes some deep reefs (20+ m) which are an uncommon feature in the northern West Coast73 and contribute to the diversity of coastal geomorphology in this segment. A fully submerged formation locally known as Gibson’s Reef occurs about two kilometres east of the Steeples74. The Buller River mouth training works also form a type of artificial rocky reef extending to depths of a few metres in a relatively brackish environment.
The rocky shores and reefs around Cape Foulwind are good examples of northern West Coast rocky coastal habitats, being significantly influenced by wave exposure and sedimentation (typically turbid waters and sand scour). This creates a distinctive environment for species that are adapted to such dynamic conditions – filter-feeding invertebrates (e.g. mussels and bryozoans), robust seaweeds (e.g. bull kelp, coralline algae) and grazing molluscs (e.g. limpets, paua). The coastal reef fish75, seaweeds76 and estuarine communities77 are typical of the northern West Coast. Both mainland species of bull kelp are abundant in the Cape Foulwind area.
The reefs further offshore around the Steeples are less affected by sand scour, and they cover a greater depth range and provide more habitat diversity. This is reflected in greater species diversity than for the shallower mainland reefs at Cape Foulwind and elsewhere in the northern West Coast. This diversity is most apparent for coastal reef fish78 and seaweeds (including a notably high diversity of crustose coralline algae)79. To a lesser extent this pattern of greater species diversity is also true for the shore at Wall Island.
Intertidal rock platforms are relatively scarce in the Buller area, with the shoreline being more commonly dominated by large boulders among sloping or broken bedrock. Some of the most extensive intertidal reefs occur at Wall Island and at ‘Penguin Beach’ to the south of Tauranga Bay, where biologically rich mussel beds can be found. Intertidal habitats with dense cover of marine life occur particularly at Nikau, Wall Island and Penguin Beach.
Offshore, the seabed slopes gradually out across the Buller Bay towards the Challenger Plateau at a gradient of less than two degrees within the territorial limit, reaching a depth of about 100-150 m at the territorial limit. Seabed sediments grade from coarse sand beaches to muddy sediments offshore. Coastal currents vary with sea and weather conditions, and the hydrographic chart indicates an east-west bidirectional tidal current off the Buller River mouth.
|Mokihinui (Waimare) settlement is positioned
on the banks of the Mokihinui River
Photo: D Neale, DOC
|Wall Island and the seal colony walkway, with Cape Foulwind to the north
Photo: D Neale, DOC
Coastal and Marine Wildlife
New Zealand fur seals breed in rookery areas concentrated on Black Reef, the Tauranga Bay headland, and Wall Island. Fur seal pup production has been monitored at the Tauranga Bay colony since 1991, during which time between 150 and 450 pups have been born each year, with research indicating an overall trend of decline80. An additional estimated 100-300 pups are born each year on Black Reef and Wall Island81.
Hector’s dolphins occur throughout this segment in some of the highest densities recorded for this species82. They have been studied in this locality by Secchi (in press) and Clement (2006). Other marine mammals reported include blue whale, right whale, beaked whales, pilot whale, common dolphin and dusky dolphin and orca (which are thought to feed around seal colonies at the Steeples).
Burrowing seabirds (probably sooty shearwaters and/or fairy prions) nest on Wall Island83, and sooty shearwaters nest near the Tauranga Bay seal colony. Spotted shags roost on the inside of the western Buller River breakwater and also on the Three Steeples.
Native skinks have been reported among shoreline rocks in the area known as ‘The Gap’84.
Orowaiti Lagoon and the coastal wetlands flowing into the Buller River mouth support a variety of waders, waterfowl and shorebirds including threatened species such as marsh crake and bittern.
|Cape Foulwind, with Kawau Point in the middle distance and Buller River mouth beyond.
Photo: D Neale, DOC
|Carters Beach settlement and sandy beach in the foreground
Photo: D Neale, DOC
Marine Fish and Other Species
The Buller Bay marine segment, like the rest of the western coast of the South Island, supports a rich diversity of fish and invertebrate species that are fished both commercially and recreationally by a number of fishing methods including trawl, longlining, trolling, potting and set netting.
Inshore trawl fisheries are multi-species and are primarily based on flatfish (several species), red gurnard, red cod, giant stargazer, tarakihi and blue warehou. Other species taken as bycatch include arrow squid, dark ghost shark, ling, barracouta, jack mackerel, spiny dogfish, rig, school shark, sea perch, rough skate and smooth skate85.
Rock lobsters occur especially around the Three Steeples and Cape Foulwind areas.
Surveys of coastal reef fish86, seaweeds87 and shallow reef communities88 have found an abundance of species adapted to the prevailing turbid and exposed conditions of the area. A moderate diversity of 27 coastal reef fish species have been recorded in this segment which is boosted to some degree by the reefs at the Steeples89. The Steeples and Gibson’s Reef are locally known for their relative abundance of rock lobster90, while paua are reported to be more common on the mainland reefs around Cape Foulwind91.
Shellfish beds occur in parts of the Orowaiti Lagoon92,
with cockles and pipi being especially common in the lower reaches. The
lagoon is the southern known limit of an estuarine clam, Mactra tristis,
and this shellfish forms moderately large beds in the middle reaches.
5.3.3 Cultural and Archaeological Heritage
The area is known to have been occupied by Maori with numerous archaeological sites93 including a very early settlement site at Bradshaw’s Creek. European historic sites include harbour remains, tramways, shipwrecks, rock quarries and the Cape Foulwind lighthouse area. Mineral resources (e.g. gold, coal, limestone), timber, fishing, farming, tourism and conservation all feature highly in the social history of Westport and the surrounding coastal areas94.
|View from Cape Foulwind walkway
5.3.4 Recreation and Tourism
The Steeples and Gibson’s Reef areas are the most important recreational diving and fishing sites in the Westport area95 and probably in the whole of the northern West Coast. They are fished mostly for rock lobster and finfish such as blue cod, gurnard, sharks and snapper. Boat fishing also occurs in other parts of this segment.
Recreational set netting occurs on many of the beaches especially from Mokihinui to North Beach. In the Granity area, nets are often attached to stakes driven into the seabed. Most nets are set straight off the beach at low tides or in river mouths, with some set from boats launching out of the rivers.
Mussel gathering occurs especially at Nikau and in places around the Cape Foulwind area (e.g. Omau, Wall Island, Penguin Beach).
Paua are gathered at sites around the Cape Foulwind area. Cockles and pipi are abundant in Orowaiti Lagoon (especially in the lower reaches), but the extent of gathering is not documented. Whitebaiting occurs in most of the rivers in this segment. Whitebait stands occur on the Mokihinui and Orowaiti Rivers and the Buller River is particularly popular for scooping. Other recreational fishing activities (such as surfcasting and rod fishing) also occur in this segment but tend to be more dispersed.
The attractive coastal landscape, seal colony, surf beach and other features of Tauranga Bay and the Cape Foulwind Walkway provide opportunities for a wide range of recreational activities.
Other recreational activities occur throughout this segment, especially in localities close to settlements and access points. These include beach walking, motorcycling and driving, birdwatching, surfing, swimming, boating and jetskiing. Public boatramps are located on the lower Buller River at the Fishing Basin, and at Marrs Beach near the western Buller River breakwater. Boats can also be launched at places on the Mokihinui, Ngakawau and other rivers.
Coastal reserves and formed recreation areas include: the Mokihinui (Waimarie) Domain, Hector Rest Area, Les Warren Park, Carters Beach Domain, Cape Foulwind Walkway and Tauranga Bay carpark. Tourist businesses on the coast include: the Mokihinui Domain Camping Ground, Big Fish Hotel at Granity, the Seal Colony Top 10 Holiday Park at Carters Beach, and the Bayhouse Café at Tauranga Bay.
5.3.5 Commercial Use
The Westport Harbour in the Buller River is the West Coast’s largest shipping port. It is managed on behalf of the Buller District Council by Buller Port Services Ltd, a wholly-owned subsidiary of Holcim (NZ) Ltd96. Cement is the main product shipped out of the port but gravel aggregates, coal and other cargo are also handled. Ballast water is discharged by coastal shipping prior to entering the harbour, berthing and loading cargo97. Commercial fishing wharves, fish processors and related facilities, transport companies, railway operations and other industries use the harbour infrastructure. A major portion of the port’s infrastructure lies upstream of the coastal marine area.
The Buller Bay marine segment is fished by commercial fishers using a variety of fishing methods, including lobster potting, set netting and albacore trolling, with the most common method being bottom trawl98. The inshore trawl fishery in the Karamea Bight is based principally on flatfish (mostly sole, turbot and sand flounder), gurnard and red cod at a range of depths. The area is productive and can be fished in southwesterly conditions. A common trawl for local vessels is to fish from the Westport bar, parallel to the coast as far as the Mokihinui River99.
Vessels mostly operate out of Westport, but also Greymouth and Nelson. In 2000, about 13 inshore fishing vessels were domiciled in Westport – eight trawlers, two rock lobster boats, one set netter and two season-only albacore tuna trawlers100. Vessels from further afield sometimes visit or base themselves in Westport especially in the albacore tuna and hoki fishing seasons. During the summer season the fleet can increase by 60 or more vessels depending on the movements of migratory albacore. Some commercial potting for rock lobster occurs on reefs around the Steeples.
|Siltstone cliffs at Kawau Point, with
Cape Foulwind beyond
Photo: D Neale, DOC
|'Lost Lagoon', a tidal flat esturay on the
east bank of the Buller River
Photo: D Neale, DOC
There have been numerous proposals over the years for the development of
harbour facilities in the area, the largest of these not to have been implemented
being deepwater facilities extending from Cape Foulwind to the Steeples101,
another to the south of Granity102, and the reclamation
of Lost Lagoon103. The last two of these proposals
have current resource consents.
Dredging is undertaken by Buller Port Services (mostly using the 55 m bucket dredge Kawatiri) in the Buller River, Fishing Basin and the river bar. Dredge spoil is dumped at a site about 1.5 nautical miles from North Beach. Commercial extraction of gravel aggregates occurs in the Buller River above the bridge, and assists reducing gravel build-up in the harbour area. Smaller amounts are extracted by local contractors from other rivers in the area.
Mining occurs locally in two areas of this coastal segment – a small blacksanding (beach gold) operation is authorised on the Tauranga Bay beach and limestone is mined by Holcim (NZ) Ltd at quarries near Cape Foulwind for processing at the nearby cement factory.
Dairy farming is a feature of the coastal flats in rural areas throughout this segment. The Westport Aerodrome is located on the coastal strip at the eastern end of Carters Beach, providing facilities for both commercial flights and private operators.
5.3.6 Other Public Uses and Facilities
Access to this area is made for a variety of uses at numerous points along the coast. Public access can be gained to any part of the coastline from a series of roads and tracks leading to the beach, and the only significant impediments to travel along the coast are from the larger streams and rivers. State Highway 67 bridges many of the waterways a short distance upstream from the coastal marine area.
Residential areas occur along most of this segment, including Waimarie, Hector, Ngakawau, Granity, Westport, Carters Beach, Omau, and Tauranga Bay; other settlements such as Waimangaroa and Birchfield occur a short distance back from the coast.
Untreated sewage and stormwater are discharged directly to the lower Buller River. A new treatment plant is under construction.
Shore protection works have been constructed at several places including Waimarie and Granity School and in river mouth areas including Mokihinui River, Ngakawau River and Orowaiti Lagoon. The Orowaiti River and Lagoon serve as a flood overflow channel for the Buller River.
|Pied stilts on mudsnail flats at
Photo: D Neale, DOC
|Torea Rocks, with Lovers Rock in the foreground
and Chair Rock beyond
Photo: D Neale, DOC
The Westport refuse station is located at a site adjoining the Orowaiti
There are Resource Management Act coastal permits issued in this segment104 for:
- stone, pebble and sand removal (several locations)
- whitebait stands (Mokihinui River and Orowaiti Lagoon)
- stream outlet opening (Jones Creek)
- a coal export jetty facility (near Granity)
- river and coastal protection works (Granity School, Waimangaroa River and Orowaiti Lagoon)
- dredging and spoil dumping (off Buller River mouth).
5.3.7 Existing Protection and Management Areas
Coastal areas of conservation land are generally small in this segment but notable sites occur in the vicinity of Orowaiti Lagoon and North Beach (including a 20 hectare area of saltmarsh within the Orowaiti Estuary Scenic Reserve), Bradshaws Creek (Buller River Wildlife Refuge), Carters Beach Recreation Reserve, Cape Foulwind and Tauranga Bay and on the hillslopes of the Denniston and Stockton Plateaux.
Bradshaws (Martins) Creek (a tributary of the Buller River) is closed to
whitebaiting. Whitebaiting is also not permitted in non-tidal areas nor
upstream of ‘back pegs’ on the Mokihinui, Orowaiti and Buller
The area lies almost entirely within Fisheries Statistical Area FSA 35 (north from Cape Foulwind) and FSA 34 south of there, which are part of the Challenger Fishery Management Area (FMA 7). The adjoining land area is within the Buller District.
The Westport Harbour limits (mostly for the purposes of controlling navigation and shipping infrastructure matters under the maritime Transport and Harbours Acts) extend from Ngakawau to Cape Foulwind (see map).
The operative West Coast Regional Coastal Plan recognises:
- Coastal Protection Area; CPA4 Orowaiti Lagoon.
- Coastal Development Areas; CDA1 Buller River mouth, CDA4 Ngakawau.
- Culturally Significant Areas; CSA5 Whareatea, CSA6 Omau Bay, CSA7 Tauranga Bay.
- Coastal Recreation Areas; CRA2 North Beach, CRA3 Lower Buller River, CRA4 Carters Beach, CRA5 Tauranga Bay.
- Outstanding Natural Features and Landscapes; ONFL3 Cape Foulwind
- Marine Mammal and Bird Site; MMB3 Three Steeples and Black Reef, MMB 4 Wall Island and adjacent coast, MMB5 north end of Nine Mile Beach.
- Coastal Hazard Areas; CHA2 Gentle Annie to Miko, CHA3 Dean Stream to Orowaiti River, CHA4 Tauranga Bay.
|One of the Three Steeples rock stacks off Cape Foulwind
Photo: D Neale, DOC
6 Dept of Conservation unpublished reptile sighting database
70 e.g. see Neale 2007
71 Kirk, Hastie & Lumsden 1985, 1986, 1987; Hastie, Kirk & Lumsden 1986; Simpson & Fyson 1971, Furkert 1947
72 Ramsay 2006, Apperly 1997; Wright & Foster 1996; Hicks 1996; Reid et al 1996; Kingett Mitchell & Associates 1996; Stanton 1971, 1996; Kingett & Associates 1994; Neale 1989; McMillan 1983; Gower 1982; Valentine & Macky 1984; Mangin 1973; van der Linden & Norris 1973; Nevins 1938
73 Shears in prep
74 Norris 1978
75 Neale 2006b, Shears in prep
76 Harvey et al 2005, Neale & Nelson 1998
77 Rogers et al 1996
78 Roberts et al 2005
79 Harvey et al 2005
80 H. Best, pers comm 2006
81 Neale & Best 1999
82 Dawson 2001
83 Neale 2006e
84 J. Green pers comm 1999
85 Stevenson & Hanchet 2000
86 Roberts et al 2005
87 Harvey et al 2005, Neale & Nelson 1997
88 Shears in prep
89 Roberts et al 2005
90 B. Wals, pers comm 2005
91 R. Bromley pers comm 2006
92 Rogers et al 1996
93 e.g. Hooker 1990
94 MacDonald 1973
95 B. Walsh pers comm 2005
97 S. Brown pers comm 2006
98 Booth et al 2005
99 Boyd Fisheries Consultants Ltd 1996
100 Stevens 2000
101 Coode 1880
102 Kingett & Associates 1994
103 Buller Port Services 1994
104 www.wcrc.govt.nz “Maps on the Web”, June 2006