Seasonal dynamics shape the timing and intensity of bird-plant interactions but are increasingly altered due to anthropogenic disturbances such as biodiversity loss and climate change. Baseline data on these patterns are critical, especially for restored communities where threatened bird species act as both pollinators and seed dispersers.
Kauri dieback disease, caused by the soil-borne oomycete pathogen Phytophthora agathidicida, has spread through much of New Zealand’s kauri (Agathis australis) forest, killing thousands of trees. However, whether kauri dieback affects the broader biological community in kauri forests is largely unknown.
The Nationally Endangered kea (Nestor notabilis) is one of five endemic New Zealand bird species for which non-target mortality from consumption of 1080 (sodium fluoroacetate) pellet baits, used to control invasive mammals, has been recorded. Kea by-kill varies among operations, but reducing predators can deliver population-level benefits that outweigh the risks. Inclusion of bird-specific repellents within the bait matrix is possible, provided that target species (possum (Trichosurus vulpecula) and ship rat (Rattus rattus)) kills remain high.
Over 25% of endemic bird species have become extinct since the time of the first human settlement of Aotearoa | New Zealand in the mid-13th century CE. This has been attributed to multiple factors, including human impact from over-hunting, habitat loss, and the introduction of successive waves of novel mammalian predators. In this study, we analyse carbon (δ13C) and nitrogen (δ15N) stable isotope values from bulk bone collagen of 19 positively identified living and extinct bird species from the coastal pre-contact (i.e.
Sika deer (Cervus nippon) were introduced into the central North Island, New Zealand, in the early 1900s. They rapidly established, increased in numbers, and extended their geographic range, eventually displacing sympatric red deer (Cervus elaphus). Sika deer are an important game species, but they can also severely damage native forest, especially where they occur at high densities. Here, we provide the first comprehensive assessment of annual and seasonal home range and movement ecology of adult male and adult female sika deer in New Zealand.
Ecological restoration to mitigate human impacts on the environment is increasingly widespread, particularly in forest ecosystems. Exotic plantation forests have been posited as beneficial for the restoration of forest ecosystems by creating a favourable microclimate in the understorey for native vegetation to establish. Native seed dispersal into plantation forests is a vital part of this process.
Using a sequential adaptive experimental design, we successfully demonstrate that a passive eDNA detection field tool, consisting of pear-baited alkathene pipes equipped with Dacron filters for eDNA capture, can effectively monitor occupancy by a cryptic Otago skink (Oligosoma otagense) population. Detection rates using our eDNA tool were approximately 30–50% higher than those recorded by field teams historically in the Awa Nohoaka Conservation Area.
In New Zealand, predation on endemic biota by house mice (Mus musculus) is a pressing conservation issue. While rodenticides are commonly used, efficacy and bioaccumulation are a concern. Cholecalciferol (vitamin D) offers a reduced risk of bioaccumulation. Our 14-month field study assessed the effectiveness of cholecalciferol-laced bait, which reduced mouse density by up to 59% from peak levels, yet was insufficient for sustained suppression of mice to the low levels required for conservation management.
New Zealand’s native birds are particularly vulnerable to predation from introduced mammals, especially rodents and mustelids. The prolific seeding of trees during mast years triggers rodent irruptions, and the subsequent increase in mustelids can have devastating effects on native bird populations. Waitutu Forest, in Fiordland, New Zealand, has experienced declines in many of its bird populations and has been subject to pest management since 2008 to reverse these trends. A monitoring programme was established to determine the success of this management.
In an area targeted for predator control, untrapped land can act as a source of new predator recruits into the trapped area, reducing biodiversity outcomes. We investigated how increasing the size of untrapped land could drive up costs and also compromise the ability to control predators. Using an individual-based simulation model, we explored how increasing the size of untrapped land impacted rat, possum, and stoat densities and how monetary costs rise because of the need for extra trapping effort near the perimeter of the untrapped property.
