Spartina Inventory: Raglan, Aotea, Kawhia

An aerial survey of Raglan, Aotea and Kawhia Harbours was undertaken to identify locations of Spartina infestation to assist with future management. Purpose: To assess the distribution and extent of Spartina to plan for its management.

For each infestation site: date surveyed, grid reference, photo (+ bearing), size and extent of infestation, whether herbarium specimen was collected, location map and sketch of site, and a general description of site (channels, access, other vegetation, adjoining land use). 63 Spartina sites were identified in the three harbours totaling an estimated 11.74ha.

Raglan, Aotea and Kawhia Harbours.

Raglan – E2676096 N6376563, NZMG, 1:20000, AREA Aotea – E2671819 N6354235, NZMG, 1:60000, AREA Kawhia – E2668841 N6344609, NZMG, 1:25000, AREA

January – February 1999

Survey of potential Spartina habitat via helicopter, and ground surveys at low tide. A GPS position was taken at each site, and the extent of the site estimated. Frequency of collection: Once only

Spartina potentially missed, extent of infestations estimated only. Spartina may spread to other potential habitat, and infestations increase in size over time. Gaps in collection: None reported Data quality: Not reported Attribute accuracy: Good, able to distinguish between Bolboschoenus fluviatilis which can occupy similar habitat. Completeness: All potential Spartina habitat on the West Coast of Waikato Conservancy surveyed.

Inventory of data sheets + location maps. Digital Format: No

Management of Spartina as a weed of harbours.

Freely available Sensitivity/Confidentiality: None

One off survey

Additional comments: Spartina should be monitored again before and following control operation, as the infestations may have spread or changed in extent by this time. Monitoring programme is currently being prepared to assess the off-site effects of Spartina decomposition and sediment remobilization following Spartina control as per Resource consent condition. Related information: 15 Dec 2000. Niki Maniapoto of WAO, and Alan Martin from Maketu Marae, Rakaunui placed white pegs at the extent of Spartina site K20/1. Alan was to continue to monitor the site.