The alpine zone of New Zealand covers c. 30% of public conservation land and is home to a high diversity of endemic species. Predation by introduced stoats (Mustela erminea) is identified as a major threat to alpine fauna. However, a lack of biological information, such as what stoats eat in different settings, hinders efforts to focus control measures in time and space in order to achieve the greatest conservation gains. We used a biochemical tool, stable isotope analysis, to estimate stoat diet across three time-periods in the alpine zone of three national parks.
Non-native species have the ability to negatively impact ecosystems, and the recipient biodiversity they may invade. However, they must first go through a series of abiotic and biotic filters that limit their ability to spread once established, which ultimately influences their distribution across different habitats. By understanding which habitats are most vulnerable to invasion, pest managers can prioritise their surveillance areas to focus on those most at risk.
He nui nga mātauranga a te Māori (Ngai Tūhoe) e pā ana ki nga momo hua tāokeoke (Toxins) e taea ana te whakarite hei rauemi tāwai i ngā riha kīrearea, pērā anō ki nga whiu takarangi o te tāoke 1080. I whakamātauhia e matou i nga ira tāoke o roto o te hua Tutu, ki rō taiwhanga pūtaiao. Mā te wero atu ki tētahi kiore (Norway Rat) i hua mai ngā mohiotanga o te nui me te momo o ngā tāokeoke kei roto i tēnei miro Māori, me te āhua o tēnei tāoke kia mau-rohā tonu tōna tuku whakahemo (Humaneness).
The use of herbicide to control weeds in natural areas can cause non-target damage to resident native plant communities and compromise native restoration goals. We tested 'full' and 'reduced' (half) rates of herbicide (rates based on previous glasshouse trials) on the ground cover weed species tradescantia (Tradescantia fluminensis), plectranthus (Plectranthus ciliatus), and climbing asparagus (Asparagus scandens) to determine whether the reduced rate would cause less non-target damage to natives and achieve sufficient control of the weeds.
The species composition of the understory can be a key indicator of successional trajectories in the absence of disturbance at forested sites. We surveyed species composition and percent cover in the understory of 132 closed-canopy stands of 41 woody weed species throughout New Zealand as a first step in understanding potential successional trajectories in these weed populations. Twenty-seven weed species had zero, or very few, conspecific seedlings or saplings present beneath their own canopy.
Mesopredator and competitor release can lead to population increases of invasive house mice (Mus musculus) after larger introduced mammals are controlled or eradicated. In New Zealand, mammal-resistant fences have enabled multi-species mammal eradications in order to protect indigenous species. When house mice are the only mammals remaining in these biodiversity sanctuaries, they may reach a high population density, with potential consequences for their indigenous prey.
Abstract: The Department of Conservation has implemented a Biodiversity and Monitoring Reporting System (BMRS) that estimates occupancy rates and relative abundances of introduced brushtail possums (Trichosurus vulpecula) at a representative sample of sites on public conservation land. Leg-hold traps have been used to monitor possums in the BMRS, but wax tags and chew cards have logistical and financial advantages over traps.
New Zealand forests have been and are shaped by a suite of disturbance types that vary in both their spatial extent and frequency of recurrence. Post-disturbance forest dynamics can be complex, non-linear, and involve multiple potential pathways depending on the nature of a perturbation, site conditions, and history. To capture the full range of spatial and temporal dynamics that shape forest ecosystems in a given area, we need to use and synthesise data sources that collectively capture all the relevant space-time scales.
Numerous conservation projects in New Zealand aim to reduce populations of invasive mammalian predators to facilitate the recovery of native species. However, results of control efforts are often uncertain due to insufficient monitoring. Remote cameras have the potential to monitor multiple species of invasive mammals. To determine the efficiency of cameras as a multi-species monitoring tool, we compared the detection rates of remote cameras and tracking tunnels over 4 non-consecutive days across 40 sites in Wellington.
Effective biodiversity conservation in lowland New Zealand requires an understanding of the relative benefits of managing impacts of native forest loss versus controlling invasive species. We used bird count data from 195 locations across mainland northern New Zealand to examine how the abundance and richness of native forest birds varied across wide gradients of native forest cover (c. 0–100%) and intensity of invasive species control (‘eradication’, ‘high-intensity rat and possum’, ‘low-intensity rat and possum’, ‘periodic possum’ and ‘none’).