The influence of vegetation remnants and corridors on the distribution and habitat use of the Yellow-breasted tit Petroica macrocephala macrocephala (Gmelin, 1789) in Prices Valley, Banks Peninsula : A dissertation submitted in partial fulfilment of the requirements for the Degree of Masters of Applied Science at Lincoln University

Abstract

The current distribution of Yellow-breasted tit Petroica macrocephala macrocephala (Gmelin, 1789) on Banks Peninsula suggests that it is unable to persist in areas that have been extensively modified by humans (Kearton, 1979). This study tested this hypothesis by investigating the influence of corridor and remnant features on the distribution and habitat use of ti{ in Prices Valley {which is a representative example of tit habitat on Banks Peninsula. A vegetation survey consisting of 71 modified forest reconnaissance plots identified 15 forest and scrub types in the valley. The valley's corridor/remnant complex was then divided in two distinct areas (Upper Prices Valley and Lower Prices Valley) according to the distribution of these forest types. Presence/absence of tit in each remnant was determined using walk-through, 3-minute bird counts, and an artificial bird call method. Tit were only recorded in Upper Prices Valley. Lower Prices Valley is linked to Upper Prices Valley by fences, shelter belts, scattered individual plants and patches, all of which were suitable for use by tit. The absence of tit from Lower Prices Valley therefore cannot be explained by the lack of an adequate wildlife corridor system. The lack of certain forest types in Lower Prices Valley was considered to be the cause of tit absence at this site, as forest type and structure is known to influence tit behaviour and niche selection (Kearton, 1979). There was a significant (p<0.05) preference of tit for Totara forest and families of tit were only observed in this forest type. The remaining tit were concentrated in areas close to Totara forest or in the large forest remnants that had a structure similar to T otara forest. The two most important features of the forest habitat for tit appear to be i) high plant species diversity and ii) vantage points for prey scanning and boundary patrolling. Large areas of mature forest are important for tit conservation on Banks Peninsula. The results of this study suggest that the remaining large areas of mature podocarp forest need to be conserved and/ or restored. Plant regeneration around smaller remnants should also be promoted, as this will buffer the remnants and provide habitat for non breeding tit.