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Olfaction is an important sense for many animals, yet its role in foraging by herbivores is poorly known. Many plants contain volatile compounds, such as terpenes, that are not only volatile but can be toxic if ingested. Volatile terpenes can be used by herbivores to assess leaf quality, but there is little evidence for whether they are also used as a searching cue. We applied the giving-up density (GUD) framework to examine fine-scale foraging by two free-ranging mammalian herbivores, the brush-tail possum (Trichosurus vulpecula) and the swamp wallaby (Wallabia bicolor), using patches with food and an inedible matrix that varied in content of a volatile terpene, 1,8-cineole. We tested the effect of (1) increasing dietary cineole concentration, and (2) masking the food odor by adding cineole to the inedible matrix, thus overriding the smell released by the diet. In both species GUD was affected by dietary cineole; a high cineole concentration raised GUD, consistent with its role as a toxin. There was a significant effect of masking on GUD for wallabies but not for possums, suggesting that odor was an important foraging cue at the feeding patch only for the former. Differences in ecological niche and diet may explain this pattern. We suggest that herbivores, such as the swamp wallaby, opportunistically eavesdrop on plant volatiles, i.e., take advantage of the signal proffered for a different function. The cost of this eavesdropping for plants, however, is presumably counteracted by other ecological benefits of these volatiles, including a reduction in leaf consumption as a function of toxicity.

A regulatory framework allowing legal access to medicinal cannabis (MC) products has operated in Australia since November 2016. MC prescribing by healthcare practitioners (HCPs) is primarily conducted through the Special Access Scheme - Category B (SAS-B) pathway, through which prescribers apply to the Therapeutic Goods Administration (TGA–the federal regulator) for approval to prescribe a category of product to an individual patient suffering from a specific indication. The dataset collected by the TGA provides a unique opportunity to examine MC prescribing trends over time in the Australian population. Here we analysed this TGA SAS-B dataset since inception with respect to age, gender, product type (e.g., oil, flower, etc.), CBD content, indication treated, and prescriber location. Results are presented descriptively as well as being analysed using non-linear regression models. Relationship between variables were explored via correspondence analyses. Indications were classified with reference to the International Statistical Classification of Diseases and Related Health Problems (10th Revision). As of 31 August 2021, a total of 159,665 SAS-B approvals had been issued for MC products, 82.4% of were since January 2020. Leading indications for approvals were for pain, anxiety, and sleep disorders. Oil products were the most popular product type, while CBD-dominant products (≥98% CBD) accounted for 25.1% of total approvals. Approvals for flower products increased markedly during 2020–2021, as did approvals involving younger age groups (18–31 years old), male patients, and non-CBD dominant products. A disproportionate number of SAS-B MC applications (around 50%) came from HCPs in the state of Queensland. Associations between patient gender and age and/or indication with product type were found. For example, approvals for oil products were commonly associated with approvals for pain. While, overall prescribing increased dramatically over the last 2 years of analysis, stabilization of approval numbers is evident for some indications, such as pain. Current prescribing practices do not always reflect provided TGA guidance documents for MC prescribing. While acknowledging some limitations around the SAS-B dataset, it provides a unique and valuable resource with which to better understand current prescribing practices and utilisation of MC products within Australia.

The strong innate fear response shown by laboratory rodents to predator cues could provide powerful and innovative tools for pest management. Predator cues are routinely used to induce fear and anxiety in laboratory rodents for pharmacological studies. However, research on the fear response induced by predator cues in different species of rodents in the wild has been inconclusive with results often contradictory to laboratory experiments. Potential explanations for this inconsistency include the prey's: (i) physiological state; (ii) parasite load; (iii) differential intensity of perceived threats; (iv) fear learning and habituation; and (v) information gathering. In this review, we first explore current knowledge on the sensory mechanisms and capabilities of rodents, followed by the discussion of each of these explanations within the context of their implications for the use of antipredator response as a pest rodent management tool. Finally, we make recommendations on potential solutions and strategies to resolve issues in rodent management related to these hypotheses.