Nonlinear Simulations of GravityWave Tunneling and Breaking over Auckland Island

Horizontally dispersing gravity waves with horizontal wavelengths of 30 – 40 km were observed at mesospheric altitudes over Auckland Island by the airborne advanced mesospheric temperature mapper during a DEEPWAVE research flight on 14 July 2014. A 3D nonlinear compressible model is used to determine which propagation conditions enabled gravity wave penetration into the mesosphere and how the resulting instability characteristics led to widespread momentum deposition. Results indicate that linear tunneling through the polar night jet enabled quick gravity wave propagation from the surface up to the mesopause, while subsequent instability processes reveal large rolls that formed in the negative shear above the jet maximum and led to significant momentum deposition as they descended. This study suggests that gravity wave tunneling is a viable source for this case and other deep propagation events reaching the mesosphere and lower thermosphere.

The Prehistory of South Polynesia

Southern Polynesia, including New Zealand, the outlying Norfolk, Kermadec, Chatham, and Auckland Island groups was colonized after A.D. 1200 by populations from Central East Polynesia. Interaction between Eastern Polynesian and Southern Polynesian populations ceased soon after colonization, although interaction between the various outlying islands and the New Zealand population continued for possibly another 200 years. Early New Zealand populations exploited plentiful moa, a large flightless bird, and pinnipeds as food sources, hunting the former to extinction. Later horticultural activities, especially in the more clement North Island, focused on kumara or sweet potato. Although Maori society was never as hierarchical as East Polynesian populations, there is abundant archaeological and ethnographic evidence of later complex social and political systems, exchange or distribution networks for utilitarian and prestige goods, and extensive competition between groups, most prominently indicated by the approximately 7,000 fortified sites or pa distributed largely within horticultural landscapes.

Revision of the genus Megalopsalis (Arachnida: Opiliones: Phalangioidea) in Australia and New Zealand and implications for phalangioid classification

A morphological phylogenetic analysis is conducted of Australasian harvestmen previously included in the family Monoscutidae. Monophyly of Monoscutidae is not supported, and the subfamilies Monoscutinae and Megalopsalidinae are synonymised with the South American subfamily Enantiobuninae. Monoscutidae is re-synonymised with the family Neopilionidae. The analysis also demonstrates the polyphyly of species previously assigned to the genus Megalopsalis. Megalopsalis epizephyros new species, M. eremiotis new species, M. leptekes new species and M. pilliga new species are described and M. serritarsus and M. hoggi are redescribed, all from Australia. Hypomegalopsalis tanisphyros new genus and species is described from Western Australia. Megalopsalis linnaei is transferred to Tercentenarium new genus. Forsteropsalis new genus is established to include species from New Zealand (including Auckland Island): Macropsalis chiltoni (type species), Pantopsalis distincta, Macropsalis fabulosa, Pantopsalis grayi, Megalopsalis grimmetti, Megalopsalis inconstans, Megalopsalis marplesi, Megalopsalis nigra and Pantopsalis wattsi.

Philopatry and site fidelity of New Zealand sea lions (Phocarctos hookeri)

The New Zealand sea lion (NZ sea lion), Phocarctos hookeri, is New Zealand’s only endemic pinniped, and one of the worlds rarest otariids. It is classified as ‘Threatened’ based primarily on the low number of breeding sites and restricted distribution. In New Zealand, a species listed as ‘threatened’ is required to be managed to allow its recovery and removal from the list within 20 years. For NZ sea lions this is dependant on the establishment of new breeding areas. However, understanding the recolonisation processes for pinnipeds is still in its infancy with factors such as philopatry needing more research to understand individual dispersal and the recolonisation process. This paper presents the first quantitative investigation into the level of site fidelity and philopatry to breeding beaches in NZ sea lions. Data from resights of NZ sea lions marked as pups from the northern Auckland Island breeding area suggest that both site fidelity and philopatry are important characteristics of this species. Our results show that overall: (1) females have a higher resighting rate than males, particularly at natal sites; (2) female non-natal resightings are predominantly restricted to locations within the northern Auckland Island breeding area (an area of ~10 km2), whereas male resightings are more widely dispersed (up to 700 km to NZ mainland); and (3) philopatry occurs for both sexes, but is more predominant in females than males, with males displaying delay related to sexual and social maturity. The colonisation of new breeding habitats rarely occurs when philopatry is strong and population density is low, stable or declining such as seen for NZ sea lions. Therefore, this research indicates that management of NZ sea lions needs to minimise anthropogenic mortality and encourage population growth to maximise density at breeding sites and encourage females to disperse to establish new breeding areas.

New Zealand species of Steneotarsonemus Beer (Acari: Tarsonemidae)

New Zealand Steneotarsonemus (Acari: Tarsonemidae) comprises three species: Steneotarsonemus (Neosteneotarsonemus) ramus sp. nov. collected from Poa litorosa in Tagua Bay, Auckland Island; Steneotarsonemus (Mahunkacarus) mayae sp. nov. found under leaf sheaths and on flower panicles of Dracophyllum strictum Hook in Awakino; and Steneotarsonemus (Steneotarsonemus) spirifex (Marchal) collected from ryegrass and pasture soil in Palmerston North and The Glen. Keys to world species of Steneotarsonemus (Neosteneotarsonemus) and Steneotarsonemus (Mahunkacarus) are provided.