West Coast Marine and Coastal Localities:
a Detailed Description of 14 Segments
5.1 Introduction
This chapter summarises information about the West Coast region at a more
detailed scale than the information presented in Chapters 2–4. The
West Coast region is divided into 14 ‘segments’, numbered from
north (Kahurangi) to south (Hope). The boundaries of each segment have been
selected for convenience of mapping (allowing a little overlap between maps).
The segments have been so chosen to ease the display of information about
the coastal and marine environment: the locations and their boundaries do
not represent any attempt to identify priorities for protection or MPA boundaries.
Each segment comprises a written description and illustrations about the
natural and human environment under a series of standard headings. To provide
spatial information on the localities, a base map and a series of smaller
maps accompany each text/photo segment.
Note: The maps are not to be used for navigational purposes.
5.0.1 Map Information Sources
a. Base Maps
The 14 large base maps show some of the main information about each segment,
such as place names, topography (both on land and in the sea) and seabed
sediments. They cover the full length of the West Coast shoreline at a scale
of 1:125,000, and extend offshore to show some or all of the 12 nautical
mile territorial limit (see Figure 5.1). In some cases, where the full extent
of the territorial sea is not included on the maps, sediment and bathymetric
(depth) information can be found in the regional maps shown in Chapter 2.
Figure 5.1
Index of segment maps
The legend on each base map explains several of the main symbols. Mapped
symbols that are not included in the legend (e.g. forest cover, coastal
rocks) correspond to map legends from the main sources – NZMS Topographical
(land) maps and RNZN Hydrographic (marine) charts1.
Land information includes topographic data (contour shading), place names,
rivers, land cover (forest, shrubland, grassland), roads and settlements
from the Land Information New Zealand (LINZ) Topo database, and public conservation
land from the Department of Conservation Geographic Information System (DOC
GIS).
Informal place names of localities that have locally known names not approved
by the NZ Geographic Board are shown in single quotation marks (e.g. ‘Halfway
Rock’)
12 nautical mile limit is from the Department’s conservancy boundary
on the GIS database.
Upstream limits of Coastal Marine Area have been obtained from the West
Coast Regional Council (WCRC). These ‘cross river boundaries’
are as defined in the West Coast Regional Coastal Plan2,
and are formalised in an agreement between The West Coast Regional Council,
the Minister of Conservation and the relevant District Council.
Seabed information:
- Bathymetry is from RNZN hydrographic charts. This chart series was chosen because it contains the most detailed depth information available about the shallow subtidal zone (less than about 50 metres depth). More detailed information for the deeper areas (deeper than about 100 metres) is available from such charts as the NZ Oceanographic Institute Coastal Series Charts (scale 1:200 000)3, and the NIWA charts reproduced in Chapter 2. Notably, the NIWA charts provide much greater detail of the continental slope and submarine canyons, and they should be referred to when considering these deeper areas.
- Sediment data has been obtained from four main sources:
(b) Mitchell 1987 (north of Kongahu Pt, mapped at a scale of 1:200 000),
(c) McDougall 1975 and 1982, (offshore beyond about 5–10 nautical miles, north of Moeraki Canyon, mapped at 1: 1 000 000),
(d) RNZN 1984 (spot information south of Moeraki Canyon).
Sediment data is unavailable for the shallow subtidal zone south of the Waitaha River and for most of the coastal marine area south of about Knight’s Point. A reef area noted by Price (1983a) in the vicinity of Gibson’s Reef (Cape Foulwind) has not been included because local information4 indicates that its position is incorrectly shown, and because West Coast subtidal reefs are more completely mapped in the accompanying “4-maps” (see below). The source references use slightly different terms for the various sediment categories, even though all are based on the ‘Wentworth’ size classification. So, to ensure consistent interpretation across the whole region for the purposes of these segment maps, the categories have been grouped into five sediment texture classes.
b. Segment “4-Maps”
In addition to the base maps, a page of four smaller maps is included for each segment. These provide a summary in map form of a large amount of other information available, especially within the immediate coastal strip.
Habitats and Ecosystems
- Islands: from the West Coast Islands Inventory by Neale (2006e). This inventory is a compiled folder of information about the vegetated rock stacks and islands off the West Coast Tai Poutini Conservancy. It includes unpublished survey reports of some specific islands/stacks, ranging from a paragraph to several pages, and sometimes including more detailed maps of each island.
- Tidal wetlands: the maps characterise each of the waterways listed in Schedule 1 of the West Coast Regional Coastal Plan, as one of three main types (river mouths, tidal flat estuaries, and tidal lagoons; as defined in Chapter 2 of this report), based on classifications in Johnson & Gerbeaux 2004, Neale 2006a, and DOC inventories of West Coast wetlands. The maps do not specifically identify the very numerous small waterways that are not included in the regional coastal plan schedule.
- Beach types: the maps show the extent of intertidal sediment beaches on the West Coast, and broadly characterise each part of the coastline as one of three main beach types (sand, sand and gravel, cobble ridge; as discussed in Chapter 2)5. This mapping is done at a broad scale in the order of tens of kilometres, but the detail will be improved with the NIWA “NZ Coast” beach classification project that is presently being completed6.
- Intertidal and shallow rocky reef: the maps show the estimated extent of rocky marine substrates, derived from work by Neale (2006f) that includes an analysis of nautical charts and 1:15 000 air photos, and knowledge gained from coastal survey work completed since 1987. The maps are considered to provide a reasonable approximation of reef extent to depths of about 20 metres below sea level, mapped at a scale of 1:50, 000. It should be noted that some areas mapped as rocky reef will include patchy reef-sand areas, and that mapping accuracy is reduced where reefs may be obscured in air photos by deep or murky water.
- Fur seal colonies are derived from the West Coast fur seal colony inventory by Neale and Best (1999). This inventory is a compiled folder of information about the seal colonies in the West Coast Tai Poutini Conservancy. It includes unpublished survey reports of some specific sites, ranging from a paragraph to several pages, and sometimes including more detailed maps of each site.
- Birds: seabird, shorebird and wetland bird sites are derived from Department of Conservation and Wildlife Service records, local observations and surveys, and a range of other published and unpublished records held by the Department’s West Coast Tai Poutini Conservancy. Information about tawaki (Fiordland crested penguin) is mostly from McLean et al 1997.
- Fish and shellfish: information on shellfish beds is derived mostly from field surveys by D. Neale (DOC Hokitika) and others since 1987. The locations of some shellfish beds are deduced indirectly from persistent shell deposits on beaches.
- Plants: Coastal cress distribution is documented in Norton and De Lange (1999). Coastal herbfields have been mapped by Neale (DOC, unpublished data). Saltmarsh distributions are derived from field surveys by D. Neale (DOC Hokitika) and others since 19877.
- Coastal Permits (approved) have been obtained from the West Coast Regional Council (WCRC) Consents Manager8, as well as rivers with whitebait stands as listed in Schedule 2 of the Whitebait Fishing (West Coast) Regulations 1994.
- Coastal Permits (unrecorded) are resource uses and activities occurring in the coastal marine area that are not listed in the WCRC database. The information for these has been obtained from local knowledge and observations during field surveys and site inspections. The legal status of such uses and activities is generally undetermined in this report, but will likely include some that are unauthorised, and others that are ‘permitted activities’ under the Regional Coastal Plan that are not required to have a coastal permit.
- Mineral tenements: information is from the Department’s database of authorisations under the Crown Minerals Act, and the maps include only those extending into the coastal marine area.
- Public access: this is derived from information collated by Neale (2006d) from personal observations, DOC field staff, and others. Base data was mapped at a scale of 1: 50, 000, initially compiled for the conservancy’s marine mammal stranding response plan. Boat access routes mark known regular launching sites and routes.
1. Regional Coastal Plan Areas have been obtained from the West Coast Regional Council (WCRC) GIS computer database, and show those areas defined in Schedules 2 (Coastal Management Areas) and 3 (Cross Boundary Areas) of the West Coast Regional Coastal Plan9.
2. Public conservation land maps the extent and status of lands administered by the Department of Conservation. The maps do not distinguish between land inside and outside the coastal marine area.
3. Other management areas: closed whitebaiting areas are those areas closed to whitebaiting under the Whitebait Fishing (West Coast) Regulations 1994. Topuni sites, nohoanga sites and Statutory Acknowledgement Areas are as defined by the Ngai Tahu Claims Settlement Act 1998.
1 RNZN 1987
2 West Coast Regional Council 2000
3 Carter 1981, Norris 1979, Eade 1972, Norris & van der Linden 1972
4 I McKenzie pers comm 2006
5 Neale unpublished DOC data
6 T Hume pers comm 2006
7 e.g. Neale 1998a , Rogers et al 1996, Neale et al 1993
8 C Dall, pers comm 2006
9 West Coast Regional Council 2000