invasive species

Factors affecting home range size of feral cats: a meta-analysis

Managing invasive species requires knowledge of their ecology, including distribution, habitat use, and home range. In particular, understanding how biotic and abiotic factors influence home range can help with pest management decision-making, as well as informing native species management. Feral cats, self-sustaining cat populations that live independently of people, have caused numerous extinctions and continue to adversely affect native species globally.

Future climates are predicted to alter the potential distributions of non-native conifer species in New Zealand

Non-native conifers constitute a significant threat to the ecology and biodiversity of many of New Zealand’s native ecosystems and species. From the top down, the potential distributions of non-native conifer species are governed by climate suitability, which alongside variables such as the availability of suitable habitats and a source of propagules determines whether an area of land will be susceptible to invasion by a given species.

Current knowledge and potential impacts of climate change on New Zealand’s biological heritage

While global climate change is impacting biota across the world, New Zealand’s maritime climate is highly variable and relatively mild, so climate change is sometimes seen as a minimal threat to species and ecosystems especially in comparison to the more immediate threat of invasive species. However, climate change will alter rainfall patterns, increase the incidence and severity of extreme events, and gradually increase temperatures which will all modify terrestrial, freshwater, and marine systems.

Habitat-specific densities of urban brushtail possums

Invasive mammalian pests threaten biodiversity globally across a diverse range of habitats. The unique combination of resource subsidies and disturbance in cities can provide favourable conditions for invasion. Recent interest in urban biodiversity enhancement has increased the demand for effective urban pest control, but efforts are often hampered by a lack of understanding of the ecology of urban invasive mammals.

Individual specialists within a generalist niche: variable diet of stoats and implications for conservation

Conservation programmes aiming to suppress or remove invasive small mammal populations that threaten endemic fauna assume that eliminating an individual predator has the same effect as eliminating a conspecific in terms of decreasing risk to the prey species. However, marked between-individual variation in prey take could, at times, lead to uneven predation pressure. Such variation in the diets of introduced predators has long been hypothesised in New Zealand, suggesting that some observed rates of predation are not typical of the prey population as a whole.

Dual aerial 1080 baiting operation removes predators at a large spatial scale

As New Zealand attempts to become predator free by 2050, transitioning aerial 1080 (sodium fluoroacetate) operations from predator control to complete predator removal has become an important research objective. Aerial 1080 operations may not remove every last target animal, but they may be able to remove a very high proportion (> 0.99). We trialled a modified [dual] aerial 1080 operation for the removal of brushtail possums (Trichosurus vulpecula), ship rats (Rattus rattus), and stoats (Mustela erminea) at large spatial scale.

Using para-aminopropiophenone (PAPP) as a tool to control feral cats in Hawke’s Bay, New Zealand

The impact of feral cats on native wildlife is becoming increasingly recognised worldwide, making their management a necessity. As New Zealand’s Predator Free 2050 goal leads to larger and more ambitious landscape scale programmes, there is an important need for cost- and time-effective tools. Para-aminopropiophenone (PAPP) was first registered in New Zealand for feral cats and stoats in 2011 under the name PredaSTOP® and has higher target specificity for feral cats than currently used toxins.

Stable isotope analysis reveals variable diets of stoats (Mustela erminea) in the alpine zone of New Zealand

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.

Invasion patterns of non-native ants in natural ecosystems in warm, temperate New Zealand

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.

Investigation of tutin, a naturally-occurring plant toxin, as a novel, culturally acceptable rodenticide in New Zealand

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).