Hapua are complex and dynamic systems, and are especially vulnerable due of their location at the end of river catchments. The Hurunui River hapua is currently under pressure from the intensification of irrigation and agriculture, and a number of dam proposals in its catchment. The purpose of this research was to investigate the current conditions in the Hurunui River hapua, how they respond to the observed range of contemporary catchment and coastal processes, and to examine of the longer-term behaviour and vulnerability of the hapua. This information was then used to make predictions on how the hapua could be impacted if dams were to be built in the catchment, or if significant changes in the catchment occur. A multidisciplinary approach was used to investigate the short-term baseline conditions, and the long-term geomorphology of the Hurunui River hapua. Water characteristics were investigated over a falling tide, in different areas of the hapua, and in different energy conditions. The short-term behaviour of the hapua was investigated using hourly images from a time-lapse camera. The long-term vulnerability over decadal time scales was analysed using aerial photographs. This study showed that the flow of the river, the shape of the hapua, and the position of the outlet has a major control over the characteristics of the water. The surface area, the position of the barrier, and the width of the barrier of the Hurunui River hapua have been variable historically. From this research, it is predicted that the greatest impact on the Hurunui hapua would result if there is a dam related change the shape and outlet of the hapua to a state that reduces water residence time and decreases water quality. It is also predicted that if the outlet is maintained at the northern end of the hapua, and no ponded areas are present, that there would be the least problems with water quality. The findings of this research have improved the understanding of the water characteristics and processes of the Hurunui River hapua, and how they respond to change.

All kiwi species (Apteryx spp.) have suffered serious decline since human arrival and are nowa-days threatened on the New Zealand mainland. One of the most elusive, and as a result least known among the different kiwi species, is the great spotted kiwi (Apteryx haastii). Hence, little is known about the current status of the remaining great spotted kiwi populations or their popu-lation dynamics. Three main ‘natural’ populations are found in Northwest Nelson, the Paparoa Range and in the Arthur’s Pass Hurunui district. In 2007, the Department of Conservation started a great spotted kiwi population dynamics study in the North Branch of the Hurunui, the area where this research project was conducted. Kiwi workers of the Department of Conserva-tion (Waimakariri area office) captured and VHF radio-tagged 11 kiwi between March and July 2007 in the North Branch and started to collect radio tracking and activity data. To improve this existing data set, 10 of the 11 birds were intensely radio tracked using triangulation and homing techniques during December 2007 to April 2008 for this Master’s research project. Estimated home-range sizes for great spotted kiwi in the North Branch varied between 19.59 ha and 35.41 ha, with a calculated mean of 29.3 ha for adult birds. The kiwi population in a defined research area of 60 km² in the Hurunui North Branch was estimated to be around 290 birds. The density for the whole area monitored by the Department of Conservation in the North Branch was esti-mated to be 2.25 pairs per km² plus subadults or in other terms 4.83 birds per km². These density estimates are much higher than results of earlier studies in the Arthurs Pass/Hurunui district. Movement plots of three bonded pairs showed that partners stayed in territories they shared. Nevertheless pairs shared only in 5% of days (n=38) shelters but regularly met during night and kept in contact via calls especially prior to meetings. Nightly travel distances varied between 488-1657 m. Furthermore, the most frequent travel distances covered per hour ranged between 50-150 m. The results of this study provide information for other kiwi researchers and raise ad-ditional questions for other projects regarding great spotted kiwi biology, behaviour and dynam-ics still need to be answered (e.g. habitat requirements). Finally, the results of this study alone are poor indicators of current population health, but they do provide a scientific baseline for any subsequent population monitoring for the great spotted kiwi population status and health in the North Branch area. If future monitoring shows that the great spotted kiwi population is at risk, suitable management actions can be applied and their success can be correctly evaluated.