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Arthropods are often ignored or under-sampled in biodiversity and conservation assessments because of their large diversity, small size and lack of taxonomic guides. Rapid biodiversity assessment programmes have been established to assess these groups accurately. A COBRA (Conservation Oriented Biodiversity Rapid Assessment) protocol consists of an intense sampling of a habitat using the optimal combination of sampling methods. We set a basis for future protocols of measuring spider biodiversity in exotic pastures in New Zealand. Overall, 28 spider species were collected. There was variation in species discovery for each collection method, i.e. pitfall traps (86.6% of total species found), ground hand collection (95.4%), suction sampling (85.7%), and sweeping (25%). The various collection methods were complementary in species that were found. Of the four sampling methods used pitfall traps and ground hand collection were far more efficient at collecting spider species in pastures per sample. These findings are relevant for the future development of these protocols and ultimately, these tools will be used for assessing and monitoring biodiversity on farms and the impacts of farming methods. [ABSTRACT FROM AUTHOR]

A 2014 carcass search survey confirmed that Tiakina Ngā Manu aerial 1080 operations, undertaken to protect resident mohua (Mohoua ochrocephala) from increases to predator populations following substantial beech (Nothofagus sp.) mast events, cause mortality for Wakatipu white-tailed deer. Non-target by-kill of deer generates significant public opposition to predator control operations. We assessed if a current deer repellent (EDR) and a repellent in development (Pestex-DR) were effective at repelling captive white-tailed deer from consumption of nontoxic baits, commonly used in Tiakina Ngā Manu operations. Both repellents were found to significantly decrease bait consumption, and we observed clear displays of aversion to repellent baits by captive deer. Ten GPS collared wild white-tailed deer were then monitored following a Tiakina Ngā Manu operation using EDR in 2016. One collared deer was poisoned following the operation, confirming that EDR is not 100% effective. We recommend the most effective available deer repellent be used for future Tiakina Ngā Manu operations over the Wakatipu white-tailed deer habitat to minimise public opposition to these predator control operations. In addition, our results suggest that differences in the boundary size and shape of operations may account for some of the variability in non-target by-kill observed between studies. [ABSTRACT FROM AUTHOR]

Intensive ground-based searches for white-tailed deer carcasses were conducted in the Dart Valley/Routeburn catchments following the aerial application of 1080 (sodium fluoroacetate) cereal pellets as part of the 'Battle for the Birds'/ Tiakina Ngā Manu predator control program in August 2014. Four 100 ha areas were searched over four days. The detection rate of simulated carcasses allowed an estimation of the success rate for finding deer carcasses. All white-tailed deer carcasses located were confirmed to have muscle tissue containing traces of 1080 (range: 0.41–1.06 mg/kg). The detection rate of simulated carcasses was 78% (312/400). The adjusted number of dead white-tailed deer was 3.85 ± 0.85 (95% CI) over the 400 ha (0.96 deer/km2) suggesting a potential mortality of 146 ± 32 (95% CI) white-tailed deer in the predator control area of 15,215 ha. These results suggest that recurrent predator control operations may have implications for sustainable hunting of white-tailed deer. [ABSTRACT FROM AUTHOR]

Carabidae (Coleoptera) are commonly used as indicators of ecosystem health due to their high diversity, conservation value and relative ease of identification. Carabids were monitored at Ahuriri Scenic Reserve, Port Hills, Canterbury, from August 2007 to September 2008 using pitfall traps. Carabid captures, species richness and distribution across the reserve were compared with those found in a similar study in 1977–1978. Monthly carabid captures were highly correlated with average temperature in both studies. There was little evidence of carabids responding to habitat factors, such as leaf litter depth, pH or ground cover. However, Megadromus antarcticus was positively associated with canopy openness and ground cover, whereas Holcaspis angustula was more abundant where canopy cover was extensive and there was a relatively high incidence of bare rock. Thirteen species of carabid were recorded in 1977–1978, of which six were absent, four had decreased, one was stable and two species increased in abundance from collections made in 2007–2008. The loss of one Banks Peninsula and five New Zealand endemic beetle species from this reserve is of concern, and future work should aim to gain more detailed information on the habitat requirements of these species to assist conservation management strategies. [ABSTRACT FROM AUTHOR]

Ōtamahua/Quail Island is an 85 ha Recreation Reserve in Lyttelton Harbour, New Zealand. It is being ecologically restored and cats, hedgehogs, rabbits, mustelids and rats have been eradicated. However, the house mouse (Mus musculus) survived two eradication attempts, a bait station operation in 2002 and an aerial operation in 2009. Data on aerial bait deposition, bait degradation, mouse resurgence and non-target mortalities were collected. Brodifacoum bait deposition in many areas was considerably lower than the prescribed rate of 8 kg/ha. Mouse sign was simultaneously detected at seven sites around the island 6 months after the aerial operation. Tails were collected from trapped mice on Quail Island, the adjacent mainland and on the stepping-stone island (King Billy) to undertake DNA analysis. Little genetic discrimination was observed between samples obtained after the 2009 aerial bait operation, and samples from before or outside of the bait drop. By contrast, samples taken from a location 15 km distant were genetically distinguishable. Intensive trapping was also trialled in a 2 ha area as a possible strategy to regulate the mouse density using two trap designs and three bait types. Mouse trapping data indicated that abundance was highest in May and lowest in January. The results are discussed in terms of mouse eradication and management. [ABSTRACT FROM AUTHOR]

Control or eradication of feral cats (Felis cattus) is necessary for a number of reasons, including controlling zoonotic diseases and protecting native species in New Zealand. Estimating feral cat density provides vital information about location and logistical effort required for control operations but current methods used to estimate feral cat densities are often labour intensive and invasive, and may not provide appropriate baseline data. We determined the effectiveness of using camera traps to estimate a feral cat population compared with live-capture trapping in a semi-rural park. Camera trapping, with capture-recapture statistical modelling, was used to estimate population density of feral cats as between 1.06 and 1.19 cats/km2 with an individual detection probability of 5.3% per camera/night. Camera trapping (seven individual feral cats identified) was a valuable addition to live trapping of feral cats (four cats live trapped) and provided a cost-effective, non-invasive and potentially more accurate tool for wildlife managers and researchers to measure feral cat densities. [ABSTRACT FROM AUTHOR]

The New Zealand fur seal (Arctocephalus forsteri) passed through a population bottleneck due to commercial sealing during the eighteenth to nineteenth centuries. To facilitate future management options, we reconstructed the demographic history of New Zealand fur seals in a Bayesian framework using maternally inherited, mitochondrial DNA sequences. Mitogenomic data suggested two separate clades (most recent common ancestor 5000 years ago) of New Zealand fur seals that survived large-scale human harvest. Mitochondrial haplotype diversity was high, with 45 singletons identified from 46 individuals although mean nucleotide diversity was low (0.012 ± 0.0061). Variation was not constrained geographically. Analyses of mitogenomes support the hypothesis for a population bottleneck approximately 35 generations ago, which coincides with the peak of commercial sealing. Mitogenomic data are consistent with a pre-human effective population size of approximately 30,000 that first declined to around 10,000 (due to the impact of Polynesian colonization, particularly in the first 100 years of their arrival into New Zealand), and then to 100-200 breeding individuals during peak of commercial sealing. [ABSTRACT FROM AUTHOR]

The complete mitochondrial genome of three mustelid species, stoats (Mustela erminea), weasels (Mustela nivalis) and ferrets (Mustela furo), and the New Zealand fur seal (Arctocephalus forsteri) were sequenced using direct mitochondrial DNA extraction and overlapping long PCRs. The usual 37 mammalian mitochondrial genes (13 protein coding genes, 22 t-RNA and 2 r-RNA) were identified in all four mitogenomes. The divergence of stoats from other members of the sub-family Mustelinae was dated 4.5 million years ago. The mitogenomic data were consistent with a bear-like origin of seals. [ABSTRACT FROM AUTHOR]