pollen

Understanding the key pollinators of rare plants is important for a holistic assessment of ecosystem health, as the impact on a given species can travel through the network, affecting other species. Many specialist calcicolous (limestone-specific) plants are rare. Conservation management plans have been developed to assist in the survival of these rare plant species, but these rarely include information on pollinators.

Central Otago is one of the driest parts of New Zealand, and much of the natural vegetation of the region was lost to fires following human settlement in the 13th Century AD. Plant macrofossil and pollen records have provided detailed insights into the vegetation communities that existed in Central Otago’s lowlands at the time of human settlement, but relatively little is known about the regional vegetation patterns prior to ~3000 years ago.

We analysed pollen in short-tailed bat guano samples from Rangataua Forest and from guano and pollen found in bat holding bags used in the Kaimanawa Range, central North Island. Fifty seven percent of the pollen from Rangataua was from a previously unrecorded source and was tentatively identified as Trachycarpus fortunei (Chinese windmill palm). The significant remaining pollen was identified as Collospermum (15%) and Nothofagus (14%) from Rangataua, and Collospermum (90%) and Nothofagus (6%) from Kaimanawa.

The rapid decline in bumblebee populations within Europe has been linked to habitat loss through agricultural intensification, and a consequential reduction in the availability of preferred forage plants. The successful introduction of four European Bombus species to the South Island of New Zealand from England (in 1885 and 1906) provides an opportunity to determine how important different forage plants (also introduced from the U.K.) are to two severely threatened European bumblebee species (Bombus ruderatus and B. subterraneus).

Pollen and charcoal analyses of sediments from northern coastal Taranaki, New Zealand, show that Maori settlement impacts on the vegetation began with the burning of tall coastal forest in the mid-17th century. Forest was replaced with a fern-shrubland, and small wetlands expanded with changing hydrological conditions. This forest clearance was much later than in most regions of the country, where major forest disturbance and clearance began between AD 1200 and AD 1400.

Evidence of diet has been reported for all genera of extinct New Zealand moa (Aves: Dinornithiformes), using preserved gizzard content and coprolites, except the forest-dwelling Anomalopteryx. Skeletal features of the little bush moa (Anomalopteryx didiformis) have led to competing suggestions that it may have either browsed trees and shrubs or grubbed for fern rhizomes. Here, we analyse pollen assemblages from two coprolites, identified by ancient DNA analysis as having been deposited by Anomalopteryx didiformis.

There has been considerable ongoing debate about the extent to which the impacts of introduced deer on native vegetation have replaced those of moa, and since the 1980s there have been major changes in thinking about the impacts of deer and ratites on ecosystems. Although it has long been known that deer caused a predictable sequence of changes in forest understorey composition, recent work has shown that the foliage of species preferred by deer contains lower concentrations of fibre – and decomposes faster – than avoided species.

New Zealand’s offshore and outlying islands have long been a focus of conservation biology as sites