Research Article

Aotearoa | New Zealand’s endemic terrestrial fauna is threatened by invasive mammalian predators. Significant resources are invested controlling a subset of mammalian predators (primarily stoats, brushtail possums, and rats) to protect birds on the New Zealand mainland, including those invested in the national Predator Free 2050 (PF2050) strategy (now also including feral cats). Yet to date, there is scant evidence that predator trapping benefits mainland lizard (skink and gecko) populations, which generally require higher levels of predator suppression, including of mice.

We describe the effects of aerial 1080 operations on the tracking rates of ship rats, house mice, and mustelids in 13 New Zealand (NZ) regions across public conservation land between 2013 and 2022 using models fitted to 591 573 records of small mammal tracks collected over 24 years. Simulated managed and unmanaged tracking rates show predictable cyclic patterns of response over the six years after aerial 1080 operations, but also strong variation among regions and with environmental variation.

Variations in invasive rodent and mustelid populations in time and space have important implications for conservation management in New Zealand. We use models fitted to 24 years of records of small mammal tracks to describe long-term temporal and large-scale spatial patterns in the activity of ship rats, house mice, and mustelids (mainly stoats) across conservation land while controlling for effects of aerial 1080 operations.

The northern striped gecko (Toropuku inexpectatus) is an arboreal gecko endemic to Aotearoa | New Zealand, formally described in 2020 and primarily known from one monitored population on the Coromandel Peninsula. Little is known about the northern striped geckos’ use of habitat, which impedes monitoring, and thus limits effective conservation management. We evaluated the geckos’ habitat use via Very High Frequency radio telemetry of 32 individual geckos for three months in the summer of 2024 and compared data to the available habitat.

Seed dispersal distances drive the rate of spread for invasive plants and are strongly influenced by dispersal mechanisms. We investigated weed seed dispersal mechanisms and dispersal potential in New Zealand. We collated data on dispersal mechanisms for 318 species that produce seed in New Zealand. We modelled maximum seed dispersal distances of 286 species for which data were available using dispersal mechanism, growth form, seed release height, and seed mass.

Fenced ecosanctuaries provide critical refuges for native species vulnerable to predation and have driven major biodiversity gains. Understanding whether they can also support sustainable populations beyond their boundaries is an important next step. While previous studies have documented native species dispersing beyond ecosanctuaries, few have utilised methods that explicitly quantify dispersal and the establishment of resident birds.

Long-term monitoring is pivotal to understanding population trends in threatened species and quantifying the impact of conservation interventions. Effective monitoring methods are generally underdeveloped or absent for taxa inhabiting the alpine zone. In Aotearoa | New Zealand (NZ), the alpine zone covers c. 11% of the land mass and supports a diverse fauna of at least 34 native lizard species.

Ephemeral wetlands are naturally uncommon ecosystems that have become threatened in Aotearoa | New Zealand and include many glacially derived kettle holes (kettles) of the South Island. These kettles can be easily overlooked as wetlands, particularly when in a dry phase, thereby increasing their vulnerability.

Genomics can provide conservation-relevant insights into population size, genetic diversity, and connectivity with relatively little sampling effort. However, for frogs and other small vertebrates, invasive genetic sampling (e.g. toe-clipping) can impact animals’ long-term survival and welfare. Minimally-invasive genetic sampling methods may be required to facilitate robust conservation genomic studies of small vertebrates. In Aotearoa | New Zealand, previous genetic studies of the three native Leiopelma spp.

Control of introduced mammalian predators is important for the protection of pekapeka | lesser short-tailed bat (Mystacina tuberculata) populations, but toxins used to control these predators may also pose a risk to bats when they forage on invertebrates that have consumed toxic bait or if bats directly consume bait.