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Accurate surveys and monitoring are required to guide the conservation and management of threatened species. Some fauna species are cryptic or difficult to observe because they are nocturnal, mimic other species, conceal themselves, or can be incredibly hard to survey. Emergence and activity of these species may be related to complex environmental cues including weather and atmospheric conditions. The conservation status of New Zealand's long-tailed bat (Chalinolobus tuberculatus) is Threatened-Nationally Critical. Occurrence and activity of long-tailed bats is commonly monitored with acoustic bat detectors. However, even in locations where long-tailed bats are known to be present, they may only be detected on a subset of nights meaning that detection with acoustic detectors is imperfect. We analysed long-tailed bat detection data collected in Kinleith Forest, central North Island, New Zealand in 2006 and 2007 using zero-inflated generalised linear (mixed) effect models. We found relationships between bat detection and several environmental variables. Results suggest that bat surveys would be most effective at detecting bats when undertaken one to four hours after sunset, on nights when the temperature at sunset is above 8°C, and preferably when the temperature stays in the 8 and 17°C range during the night. Higher humidity and a light breeze may also be a desirable condition for monitoring. A night that is similar to, or slightly warmer, than recent nights may be favourable. Caution should be taken extrapolating these results to elsewhere because bats in other regions may respond differently to temperatures out of necessity. High site-specific variation in bat counts at higher temperatures and humidity occurred with zero activity often recorded. Therefore, we caution against assuming bats are absent because they have not been detected by surveys undertaken during higher temperatures and humidity conditions unless surveys have been run for multiple nights in suitable conditions. [ABSTRACT FROM AUTHOR]

Despite a growing body of evidence worldwide that bats are affected by roads, there has been little research into the effects of traffic volume on bat activity. In New Zealand, there is considerable uncertainty over whether, or to what extent, roads affect New Zealand's endemic bat populations, and this has resulted in uncertainty during the planning and consent phases of road development projects. This research investigated whether Chalinolobus tuberculatus (long-tailed bat) activity correlates with night-time traffic volume on New Zealand's highways. Bat activity was monitored at 57 traffic monitoring sites throughout New Zealand using pairs of bat detectors, with one placed beside the highway (highway) and one placed ≥ 200 metres from the highway (distant). Generalised linear mixed effects models were used to investigate the relationship between bat detections, position in relation to the highway, and various measures of traffic volume. The model that best explained the variation in bat detections was the interaction effect between bat detector position (highway, distant) and night-time traffic volume (volume). Outputs from this model show a negative relationship between bat activity and night-time traffic volume for highway bat detector units, while distant bat detector units had no discernible relationship with night-time traffic volume. These results indicate that night-time traffic volume affects the use of roads by bats, i.e. when overnight traffic increased, the probability of detecting bats decreased. Whether or to what extent this will affect the long-term viability of New Zealand's C. tuberculatus populations is a high priority for further investigation. [ABSTRACT FROM AUTHOR]

Abstract: Given climate change, species' climatically suitable habitats are increasingly expected to shift poleward. Some imperilled populations towards the poleward edge of their species' range might therefore conceivably benefit from climate change. Interactions between climate and population dynamics may be complex, however, with climate exerting effects both indirectly via influence over food availability and more directly, via effects on physiology and its implications for survival and reproduction. A thorough understanding of these interactions is critical for effective conservation management. We therefore examine the relationship between climate, survival and reproduction in Canadian black‐tailed prairie dogs, a threatened keystone species in an imperilled ecosystem at the northern edge of the species' range. Our analyses considered 8 years of annual mark–recapture data (2007–2014) in relation to growing degree days, precipitation, drought status and winter severity, as well as year, sex, age and body mass. Survival was strongly influenced by the interaction of drought and body mass class, and winter temperature severity. Female reproductive status was associated with the interaction of growing degree days and growing season precipitation, with spring precipitation and with winter temperature severity. Results related to body mass suggested that climatic variables exerted their effects via regulation of food availability with potential linked effects of food quality, immunological and behavioural implications, and predation risk. Predictions of future increases in drought conditions in North America's grassland ecosystems have raised concerns for the outlook of Canadian black‐tailed prairie dogs. Insights gained from the analyses, however, point to mitigating species management options targeted at decoupling the mechanisms by which climate exerts its negative influence. Our approach highlights the importance of understanding the interaction between climate and population dynamics in peripheral populations whose viability might ultimately determine their species' ability to track climatically suitable space. [ABSTRACT FROM AUTHOR]

BACKGROUND Invasive mammalian pests have inflicted substantial environmental and economic damage on a worldwide scale. RESULTS Over the last 30 years there has been minimal innovation in the development of new control tools. The development of new vertebrate pesticides, for example, has been largely restricted due to the costly and time-consuming processes associated with testing and registration. CONCLUSION In this article we discuss recent progress and trends in a number of areas of research aimed to achieve long-term population suppression or eradication of mammalian pest species. The examples discussed here are emerging from research being conducted in New Zealand, where invasive mammalian pests are one of the greatest threats facing the national environment and economy. © 2013 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Given climate change, species' climatically suitable habitats are increasingly expected to shift poleward. Some imperilled populations towards the poleward edge of their species' range might therefore conceivably benefit from climate change. Interactions between climate and population dynamics may be complex, however, with climate exerting effects both indirectly via influence over food availability and more directly, via effects on physiology and its implications for survival and reproduction. A thorough understanding of these interactions is critical for effective conservation management. We therefore examine the relationship between climate, survival and reproduction in Canadian black-tailed prairie dogs, a threatened keystone species in an imperilled ecosystem at the northern edge of the species' range. Our analyses considered 8 years of annual mark-recapture data (2007-2014) in relation to growing degree days, precipitation, drought status and winter severity, as well as year, sex, age and body mass. Survival was strongly influenced by the interaction of drought and body mass class, and winter temperature severity. Female reproductive status was associated with the interaction of growing degree days and growing season precipitation, with spring precipitation and with winter temperature severity. Results related to body mass suggested that climatic variables exerted their effects via regulation of food availability with potential linked effects of food quality, immunological and behavioural implications, and predation risk. Predictions of future increases in drought conditions in North America's grassland ecosystems have raised concerns for the outlook of Canadian black-tailed prairie dogs. Insights gained from the analyses, however, point to mitigating species management options targeted at decoupling the mechanisms by which climate exerts its negative influence. Our approach highlights the importance of understanding the interaction between climate and population dynamics in peripheral populations whose viability might ultimately determine their species' ability to track climatically suitable space., (© 2017 The Authors. Global Change Biology Published by John Wiley & Sons Ltd.)