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Small mammalian predators can have low population densities, as well as cryptic and highly mobile behaviours, making these species challenging to manage. Monitoring tools such as camera traps, hair traps and footprint tracking devices can help detect cryptic species, but they require an animal to approach and, in most cases, interact with a device. They also have limited capacity to help capture animals. Wildlife-detection dogs can detect a wide range of species with a similar or higher efficiency than do other methods, partly because they are much less dependent on volitional decisions of target animals to interact with devices. By following scent trails, dogs can track down animals that actively avoid capture or detection. Dog-handlerteams also have another advantage, namely, the handler can mount a rapid managementresponse to capture orremove animals assoon asthey are detected.We review ways in which dog-handler teams can contribute to active management of small mammalian predators by combining the dogs’ ability to detect animals with their handlers’ ability to mount a rapid response. [ABSTRACT FROM AUTHOR]

Cats (Felis catus) are among the most damaging invasive predators in the world, and their impacts in Aotearoa New Zealand (NZ) are particularly severe. However, unlike the invasive predators that are targeted for eradication under the Predator Free NZ initiative, cats are also highly valued by people and therefore will likely remain widespread in NZ for the foreseeable future. This raises the question of how to manage the impacts of cats, which include predation, competition, and disease affecting native species, livestock, and humans. Appropriate management actions will depend on land use (e.g. urban areas vs wilderness), the values to be protected (e.g. wildlife, human health), as well as safety, humaneness, social acceptability, and cost-effectiveness. We review current knowledge on the impacts and management of cats in NZ and overseas, identify knowledge gaps preventing effective management, and suggest approaches for research to address these gaps. Our suggested research priorities include: (1) improved methods for monitoring cats and their impacts on natural, social and economic values, (2) development of humane, effective, and socially acceptable methods to manage the impacts of cats, (3) engagement with cat owners to improve outcomes for cats, people, and the environment, and (4) investigating potential indirect ecological effects of cat control, such as ecological release of prey or competitors. [ABSTRACT FROM AUTHOR]

As a major threat to New Zealand’s biodiversity, feral cats (Felis catus) are the subject of planned eradications on a number of offshore islands, including Rakiura Stewart Island. We used camera traps to estimate population density of feral cats on the north-east coast of Rakiura, and to investigate their movement behaviour and detection probability. We also used camera footage to compare the consumption of two types of non-toxic sausage baits (chicken and rabbit) with a view to future use of toxic baits. Population density of feral cats was likely between 1 and 2 cats per km². Non-target species (rats and possums) removed more than half the baits, greatly reducing bait availability for feral cats. Deer and birds (including kiwi) encountered baits but did not eat them. Cats had an apparent preference for chicken over rabbit baits, although small sample sizes prevent firm conclusions. Both bait types appeared to decline rapidly in palatability, and no baits were consumed by cats more than 5 days after deployment. Future trials and baiting regimes should consider ways to improve bait availability. Increased bait density, exclusion of rats and possums and/or more frequent replacement of baits will likely increase encounter rates by feral cats. [ABSTRACT FROM AUTHOR]

In order to conserve important biodiversity values, eradication of feral cats (Felis catus) is planned on Auckland Island in the New Zealand subantarctic region. This eradication will require detailed knowledge of the abundance, distribution, movement behaviour and detection probability of cats on the island. We investigated these parameters on a peninsula at the northern end of the island using live trapping, camera trapping, and scat searches with and without detection dogs. Here, we compare the results of these methods, and discuss their utility for the planned eradication. Four cats were captured and fitted with GPS collars. Camera traps with 500 m spacing detected all these individuals on multiple occasions, and at multiple locations. At least 12 other individuals were also captured on camera. Excluding every second camera (to simulate 1000 m spacing) resulted in failure to detect 32% of known individuals. Population density estimates from camera trapping varied from 0.7–1.0 cats km-2. Humans found 29 cat scats, and dogs found 33. Genetic analysis estimated that these came from a minimum of ten individuals. Camera trapping should be repeated during the operational and confirmation phases of the eradication to monitor spatial and temporal variation in cat density, detect survivors, and help confirm eradication success. Scat collection, with and without dogs, can supplement data from camera trapping. With larger sample sizes of scats, DNA profiling may also allow cat abundance to be estimated. [ABSTRACT FROM AUTHOR]

Monitoring is an important component of pest species management in New Zealand. Chew cards are increasingly used for mammalian pest monitoring. They are effective for measuring the relative abundance of rats (Rattus spp.), but their effectiveness for measuring hedgehog (Erinaceus europaeus) relative abundance has not been tested. Camera traps are also increasingly used as a monitoring tool, but there has been little calibration with other methods. We investigated whether chew card indices and camera indices for hedgehogs and rats gave consistent monitoring results. We also explored the relationship between the relative abundance of rats and hedgehogs using these indices. Hedgehog and rat chew card indices both showed a positive relationship with the respective camera indices for each taxon. However, cameras had fewer detections than chew cards when relative abundance was low (particularly for rats). Interference by rats did not appear to affect detection of hedgehogs with chew cards. Although not a strongly supported result in our study, the relationship between rat and hedgehog relative abundances requires further study and is a reminder that single-species pest control may not produce desired biodiversity outcomes. [ABSTRACT FROM AUTHOR]