Spartina spraying trials, Kawhia Harbour.

The purpose of these trials is to assess the effects of Gallant on the flora and fauna of Kawhia Harbour, as required by a resource consent condition to apply herbicide Gallant in the CMA. Pre and post spray surveys of macroinvertebrates were undertaken in control and treatment sites. Purpose: To assess the effects of a herbicide spraying programme in relation to the flora and fauna, geomorphology and hydrology of Kawhia Harbour, as required by a resource consent condition to apply herbicide Gallant in the Coastal Marine Area.

Macroinvertebrate diversity and density at two trial sites, and two control sites.

Upper reaches of Te Waitere, Kawhia Harbour.

Upper reaches of Te Waitere, Kawhia Harbour -

March, June and October 1994.

Two trial sites, and two control sites. Three 4m x 1m quadrats at each site. Mainly Amphibola and Potamopyrgus species were counted before and after the spraying. Amphibola were painted to aid re-identification of individuals. Two cores from each site were sieved through 5mm and all macrospecies recorded. Frequency of collection: Once only

Poor relationship of data collection to herbicide application. Cause-effect analysis unable to be made. Gaps in collection: No collection of flora data. Limited detail of fauna species. Data quality: No relationship to standardised methods. Attribute accuracy: Not reported Completeness: Incomplete data collection to test the objective.

report Digital Format: MS Word

Management of Spartina as a weed of harbours.

Freely available Sensitivity/Confidentiality: None

One off survey

Additional comments: Resource Consent requires environmental monitoring as a consent condition to assess the off-site effects of spartina decomposition and sediment remobilization. Related information: NIWA spraying trials.