responses

We sampled soils and vegetation within and outside two sheep and rabbit exclosures, fenced in 1979, on steep sunny and shady slopes at 770 m altitude on seasonally-dry pastoral steeplands. The vegetation of sunny aspects was characterised by higher floristic diversity, annual species, and low plant cover. Here the exotic grass Anthoxanthum odoratum dominated on grazed treatments, and the exotic forb Hieracium pilosella on ungrazed. Shady aspects supported fewer, and almost entirely perennial, species.

The challenge of community restoration is to understand and exploit the principles of ecological succession at all seral stages, by complementing and accelerating the processes of colonisation and regeneration. The main aim is to construct self-sustaining,appropriate communities, connected in the landscape, that meet conservation, landscape and crop production goals. Research, to date, has been biased towards the plant and soil components with little consideration for the animal element.

We studied the ecology of a high-density population of stoats in Fiordland, New Zealand, in the summer and autumn of 1990-91 following a Nothofagus seeding in 1990. Results are compared with findings from the same area in 1991-92, a period of lower stoat density. In the high-density year, minimum home ranges (revealed by radio-tracking) of four females averaged 69 ha and those of three males 93 ha; range lengths averaged 1.3 km and 2.5 km respectively. Neither difference was statistically significant.

The anti-predator behaviours of a New Zealand freshwater crayfish (Paranephrops zealandicus) to the native long-finned eel (Anguilla dieffenbachii) and the introduced brown trout (Salmo trutta) were investigated. Crayfish modified their behaviour in the presence of both trout and eels. However, a significantly greater number of defensive chela displays and swimming responses were made to eels than trout. Crayfish were able to use chemical cues from skin mucus to detect eels but not trout.

Changes in density and breeding of the house mouse (Mus musculus) in a New Zealand forest dominated by hard beech (Nothofagus truncata) were monitored for 2.5 years. Mice bred during winter and increased dramatically in density only during a beech mast year. Mice readily ate the endosperm and embryo of hard beech seed in die laboratory and chemical analysis showed it to be a very nutritious food source, similar in quality to Fagus beech seed in the northern hemisphere.