HABITAT USE AND SELECTIVITY BY THE BROWN KIWI (APTERYX AUSTRALIS MANTELLI) IN A PATCHY ENVIRONMENT

Abstract

The use of different during foraging, roosting, social behavior, and nesting was studied in the North Island Brown Kiwi (Apteryx australis mantelli) with the use of radio telemetry. We chose a forest with a patchy distribution of native and introduced habitat types, the Waitangi Forest, to compare habitat availability with habitat use within the ranges of transmitter tagged individuals. During their nocturnal activity phase, Brown Kiwis native forest and seral vegetation over man-made pine forest, marshes, and roads/pasture. During the daytime, kiwis roosted preferentially in marshes and successional vegetation. Social behavior, mostly calling, occurred in the same as did all other nightly activity. Nest sites were preferentially located in or within 25 m of native or seral vegetation. These are selectively used by chicks during foraging in their first weeks after hatching, when chicks are only able to walk short distances. Habitat types seem to be used selectively by kiwis because of their availability of food and shelter sites, regardless of whether they are natural or anthropogenic habitats. Additionally, the needs of young have to be considered when spacing patterns of adults are interpreted. Territories included a certain area of preferred habitats irrespective of total territory size. With sufficient access to these patches kiwis are able to survive even in poor like pine forests. Only minor changes in forest management practices (e.g. allowing for wide road margins and preserving remnants of native forest and marshes) would suffice to greatly support the survival and propagation of kiwis. We discuss the importance of the selective use of small habitat patches as a pre- condition for the ability of kiwis to settle in a wide variety of environments, both natural and modified. Received 13 December 1993, accepted 1 April 1994. THE BROWN Kiwi (Apteryx australis) typically is regarded as an inhabitant of the native forests of New Zealand, most of which have been de- stroyed by human settlement and agricultural exploitation (Robertson 1985). Recent evidence suggests, however, that kiwis are capable of liv- ing in a diverse range of habitats. Populations have been observed in exotic pine forests (Col- bourne and Kleinpaste 1983, 1984, Taborsky and Taborsky 1991, 1992), regenerating forest, and overgrown pasture (Potter 1989), lowland tus- sock grassland (pers. obs.) and even in sand- dunes (pers. obs., R. Colbourne pers. comm.).