New Zealand

Evidence for arrested successional processes after fire in the Waikare River catchment, Te Urewera

Anthropogenic fire has transformed New Zealand’s vegetation. Small-scale historical Māori fires in the forests of Te Urewera National Park, North Island, initiated forest successions that were dominated early on by Kunzea ericoides (Myrtaceae), and later by Knightia excelsa (Proteaceae) and Weinmannia racemosa (Cunoniaceae). Previous work in these forests suggested that the more recent of these successions, initiated after the arrival of deer in the late 19th century, have failed to recover to pre-fire composition and structure.

An inventory of the status and origin of New Zealand estuarine systems.

Estuaries are vulnerable, unstable areas sensitive to the impact of man, because they are at the interface of two contrasting environments in which the results of environmental changes induced by man are focused. This study presents data on the extent, character, status and on the number of surveys of New Zealand estuaries. The widest possible interpretation of the term estuary has been used so as to produce the most comprehensive list.

Conservation of rare and threatened plant taxa in New Zealand—some principles.

Deficiencies in knowledge of New Zealand plants are outlined, particularly with regard to conservation status and distribution. In an effective and integrated approach to the documentation and study of rare and endangered plants four aspects must be considered: documentation of individual taxa, provision of effective protective legislation, preservation of populations in the wild and in cultivation, and education of both the general public and botanists.

Lizard populations on islands with and without Polynesian rats, Rattus exulans (Peale).

On three island groups off the northeast coast of New Zealand, fewer lizard species and markedly fewer individuals occurred on islands inhabited by Polynesian rats or kiore than on other islands without rats. Nocturnal, ground-dwelling lizards that forage in the open were most affected, which suggests that predation by kiore is the cause. The generally low densities and disjunct distributions of some lizards on the New Zealand mainland may have resulted from the introduction of kiore at least 600 years ago

Estimating abundance, age structure and sex ratio of a recently discovered New Zealand tusked weta Motuweta riparia (Orthoptera, Anostostomatidae), using mark-recapture analysis

Estimates of abundance, age structure and sex ratio are essential for monitoring the status of populations. We report the first attempt to reliably estimate these parameters in a population of the recently discovered Raukumara tusked weta (Motuweta riparia), which is found almost entirely near streams. On two occasions we searched a 211-m section of creek for 4–5 successive nights and individually marked all weta. We estimated abundance of adults and juveniles using closed-population mark-recapture analysis.

Effects of an aerial 1080 possum poison operation using carrot baits on invertebrates in artificial refuges at Whirinaki Forest Park, 1999 – 2002

The effects of an aerial 1080 possum poison operation using carrot baits on invertebrates in Whirinaki Forest Park are described from an un-replicated study of artificial refuges attached to tree trunks. Auckland tree weta (Hemideina thoracica), cave weta (Pharmacus sp.

Ground invertebrate fauna associated with native shrubs and exotic pasture in a modified rural landscape, Otago, New Zealand

This study examined whether the diversity and relative abundance of ground-dwelling invertebrates changed in relation to type of vegetation cover. Invertebrate taxon diversity and relative abundance were assessed with pitfall traps placed under the native shrubs Olearia bullata and Coprosma propinqua, and in surrounding patches of exotic pasture. A total of 1935 invertebrates and at least 152 invertebrate taxa were recorded from 49 pitfall traps. The number of native taxa was c.63% of all taxa recorded, whereas exotic invertebrates represented only c.9%.

Is Pittosporum patulum Hook. f. threatened by pest herbivory in eastern South Island, New Zealand?

We examined the threat status of the low tree Pittosporum patulum throughout its range in eastern South Island, based on plot-based sampling of habitat, defoliation by mammalian herbivores, demographic and dieback characteristics. Using environmental modelling (Land Environments of New Zealand), we found no explanation for the ‘gap’ in its disjunct distribution from Nelson–Marlborough–north Canterbury to south Canterbury as a component of upper montane Nothofagus forest and non-Nothofagus subalpine scrub.

Mountain beech seedling responses to removal of below-ground competition and fertiliser addition

We examine the height growth, diameter growth and below-ground allocation responses of mountain beech (Nothofagus solandri var. cliffortioides) seedlings to the experimental removal of root competition through root trenching and the addition of fertiliser within relatively intact-canopied mountain beech forest in the Craigieburn Range, Canterbury. Trenching and trenching combined with fertiliser increased relative height and diameter growth of mountain beech seedlings above that of controls.