phenology

Fruit-eating animals play a key role in spreading non-native environmental weeds, via seed ingestion and subsequent dispersal. We reviewed available information on dispersal of fleshy-fruited environmental weeds in New Zealand. We found almost a third (32.9%) of 295 environmental weed species in New Zealand have fleshy fruits adapted for internal dispersal by animals. Fruiting phenology differs between weeds and native plants, with many weed species fruiting from late autumn until early spring (May to September) when native fruits are scarce.

Population densities of the endemic red admiral butterfly, Bassaris gonerilla, were monitored over two summers on Banks Peninsula, New Zealand. Egg-laying usually begins in September and ends in late May. Peaks in egg, larval and adult densities suggest that B. gonerilla completes two full generations per season and in favourable years, a third generation is started but not completed. Population density was lower in a low-rainfall season probably because of the lower survival and nutritional quality of the host plant, Urtica ferox.

Hihi (or stitchbird, Notiomystis cincta) is a rare honeyeater endemic to the North Island of New Zealand. Hihi were translocated from Little Barrier Island to Mokoia Island, Lake Rotorua, in 1994. Mokoia is a small (135 ha) island with secondary vegetation, so there was some doubt as to whether the island had sufficient diversity of fruit and nectar sources to support a hihi population. This paper reports data collected in the year after the translocation on the density, distribution and phenology of plants likely to be used by hihi. We address the following questions.

We analysed biomass allocation of Pleurophyllum speciosum (Asteraceae) and Anisotome latifolia (Apiaceae) to explore the 'megaherb' phenomenon, the apparent importance of large-leaved, colourful forbs on southern oceanic offshore islands. The two species had similar shoot dry weights, with high leaf:stem ratios. Even within the megaherb form there are differences in shoot allocations, with Pleurophyllum investing more biomass in rhizome than foliage, compared with Anisotome.

Food of the North Island kaka (Nestor meridionalis septentrionalis) on Kapiti Island was identified while quantifying the foraging activity of nine radio-tagged birds from March 1991 to January 1992. Additional food types were identified by opportunistic observation of feeding birds and qualitative examination of nestling faeces. A diverse range of food was taken, including wood-boring invertebrates, scale insects, seeds, nectar or pollen, fruits, and sap.

Scutellaria novaezelandiae is a small herb restricted to the Nelson/ Marlborough region. Aspects of its ecology were studied to assist in the management of wild populations. An absolute estimate of abundance is not possible as individual Scutellaria plants are indistinguishable and it grows in small patches up to 20 m². There are probably between 50 and 100 such patches in podocarp-beech forest below 200 m a.s.l. on freely drained alluvium and colluvium.

The diet and food preferences of the kererū (Hemiphaga novaeseelandiae) were studied in Whirinaki Forest Park, central North Island, New Zealand, during February 2000 – March 2001. The study was carried out in two areas of podocarp–hardwood forest, Oriuwaka (1750 ha) and Otupaka (1830 ha). Fruit dominated in the diet at both sites (65% in Oriuwaka, 87% in Otupaka), but there were seasonal changes. Foliage and flowers were more important in the diet in winter and spring, but the timing of the switch from fruit to foliage differed between the areas.