No abstract

Roads are an omnipresent feature of the contemporary landscape and are associated with extensive ecological impacts, including habitat degradation, changes in animal behavior, and increases in wildlife mortality. Road ecology has grown into a dynamic multidisciplinary research area within the environmental sciences, aiming to avoid, minimize, and offset the impacts of road use. However, current best practices in mitigation are often incomplete, failing to account for the full suite of environmental problems that roads create and for the causal mechanisms of those problems. We highlight one environmental problem that is largely absent from the road ecology literature – air pollution from motorized vehicles and from road use. Using recent examples, we discuss our current understanding of the ecological effects of air pollution and describe ways to incorporate it into a comprehensive road ecology research framework. Failure to develop such a framework will result in an incomplete representation of the impact that roads have, and will likely diminish the effectiveness of mitigation strategies.

Data accessibility statement Should the manuscript be accepted, data supporting the results will be archived Dryad and the data DOI will be included within the article.

Volatile organic compounds (VOCs) serve as important infochemicals, mediating several ecological interactions including herbivory and pollination. Atmospheric pollutants including traffic‐related air pollution may impair the detection of VOCs used by insects in insect–plant interactions. We investigated the indirect effect of petrol exhaust pollution on olfactory learning and memory (short and long term) in honey bees. Using appetitive olfactory conditioning, we trained bees to learn one of four floral VOC profiles; linalool, dipentene, myrcene and geranium. VOCs were unpolluted or polluted with exhaust collected from a petrol generator. Exhaust emissions included concentrations of CO (246.07 + 17 ppm), NO (20.50 + 6.90 ppb) and NO2 (20.93 + 0.05 ppb) consistent with those typically encountered in urban areas and near roads. Once bees had learnt the training VOC, we tested whether they could recognise that VOC 1 h, 24 h and 48 h post‐training. Bees took significantly longer to learn polluted VOCs and forgot them faster than unpolluted ones. We also tested the ‘masking’ potential of pollution on floral VOCs. Using gas chromatography mass spectroscopy we noted differences in the chemical profile of polluted versus unpolluted VOCs and tested whether bees could recognise polluted VOCs if trained using unpolluted ones. For several VOCs tested, bees could distinguish between polluted and unpolluted VOCs. Ultimately, our results show that air pollution changes the recognition and retention of floral VOCs by bees which may consequently impact foraging efficiency.

Ground-nesting bees are largely undervalued, both in terms of their use as model species for behavioural studies, and in terms of their agricultural benefit as pollinators in crop systems. But, why? One potential barrier limiting their use as model species may be our understanding of how to effectively establish and maintain groundnesting bees in the laboratory. Here we review how artificial nests are used to study ground-nesting bees and provide guidelines for building, starting and maintaining artificial nests. Ultimately, appropriate design and maintenance of artificial nests will allow researchers to explore a suite of interesting questions related to this important group of pollinating insects, from natural history to the origins of eusociality and the effects of environmental contaminants. ground-nesting bee / artificial nest / rearing / Lasioglossum