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Many amphibians in Europe and North America regularly use under-road tunnels during dispersal. However, such structures have not been shown to mitigate the impacts of road mortality on frog populations in Australia. We tested the behavioural response of three Australian frog species to a 12-m amphibian under-road tunnel in controlled ex situ conditions. In April and October 2012, we tested 34 striped marsh frogs Limnodynastes peronii, 54 green and golden bell frogs Litoria aurea, and 15 broad-palmed frogs Lit. latopalmata. The overall proportion of frogs entering the tunnel (tunnel usage), and entering and exiting the tunnel at the opposite end (tunnel efficiency), among the three species was 0.13 and 0.05, respectively. The proportion of usage for Lim. peronii, Lit. aurea and Lit. latopalmata was 0.21, 0.07 and 0.13, respectively. The mean time taken for an individual to enter the tunnel was 14 min 22 s. There was some evidence of directionality in the movement of Lim. peronii and Lit. aurea within the experimental arena. Tunnel usage was not likely related to air temperature, humidity or light levels inside the tunnel, but requires further investigation. Our study showed that there was low usage of the under-road tunnel compared with the relatively high usage rates of tunnels by amphibians in the Northern Hemisphere. Our results demonstrate that the effectiveness of wildlife tunnels in mitigating the impact of roads on frog species in Australia and tropical regions requires further investigation. We recommend testing these tunnels once installed under several roads near wetlands to assess how frogs respond to them during the breeding period. bs_bs_banner Animal Conservation. Print Frog usage of an under-road tunnel A. J. Hamer et al.

Background Since 2013, badger culling has been part of the UK Government's strategy for controlling bovine tuberculosis (bTB) within a high‐risk area (HRA) in England. Government surveillance data now enables an examination of bTB herd incidence and prevalence, its headline indicators, within and outside cull areas over the period 2009–2020. Methods Analysis compared herd incidence and prevalence data from within and outside badger culling areas. A range of models (GLMs, GLMMs, GAMs and GAMMs) were used to analyse incidence and prevalence in culled and unculled areas using frequentist and Bayesian approaches. Change in incidence across ten county areas within the HRA for the period 2010–2020 was also compared. Results Analyses based on Defra published data using a variety of statistical methodologies did not suggest that badger culling affected herd bTB incidence or prevalence over the study period. In 9 of 10 counties, bTB incidence peaked and began to fall before badger culling commenced. Limitations There are limitations around the data available on culling location, temporal information and other confounding factors. As such, further analysis of any future datasets that may be released on bTB levels in areas where badger culling has been implemented is warranted. Conclusion This examination of government data obtained over a wide area and a long time period failed to identify a meaningful effect of badger culling on bTB in English cattle herds. These findings may have implications for the use of badger culling in current and future bTB control policy.

Aspects of design and analysis of the Randomized Badger Culling Trial in England are considered with respect to the relationship between proactive badger culling and incidence of new bovine tuberculosis cattle herd breakdowns. Assumptions made by the Independent Scientific Group report in 2007 on the RBCT experiment including its design are reviewed. Independent re-evaluation of RBCT data does not show a statistically significant relationship between proactive badger culling and new herd breakdown. Better understanding of the pathogenesis of the disease since the RBCT experiment and an alternative statistical approach challenges the methods, analyses and conclusions of the effects of proactive culling in RBCT. Hence the validity of its current application in large scale badger culls in England since 2013 is questioned.

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