Association of excessive precipitation and agricultural land use with honey bee colony performance

Context From landscape variables to weather, multiple environmental factors affect honey bees and other pollinators. Detailed honey bee colony assessments in a variety of landscape and weather conditions offer the opportunity to develop a mechanistic understanding of how landscape composition, configuration, and weather are associated with colony nutrition, demography, and productivity. Objectives Our objective was to test if weather and landscape characteristics (e.g., agricultural versus forested land use) are associated with different honey bee colony outcomes (foraged nectar mass, foraged pollen mass, pupal population size, and adult population size change). Methods We collected detailed colony measurements on over 450 honey bee colonies over four years across an agricultural-to-forested land use gradient in Michigan, USA. Results We found that higher than normal precipitation in the preceding spring and fall was negatively correlated with colony size change and with foraged nectar mass, respectively. Sites surrounded by less agricultural land and more forested land also had fewer pupae by the end of summer. Conclusions These inter-dependent colony metrics offer insights into environmental-plant-pollinator dynamics. Our finding that extreme weather events, associated with climate change, are negatively correlated with colony performance point to likely lagged effects of weather on pollinator floral resources. Landscapes managed with climate-resilient, temporally continuous floral resources are likely to support pollinators. Capturing extreme weather phenomena in field studies is a valuable way to investigate the associations between land use, climate change and biological systems. However, caution should be taken in overinterpreting observational studies, so further research is needed

The professionalisation of academics as teachers in higher education

This position paper is an outcome of the European Science Foundation’s Exploratory Workshop ‘The Impact of Training for Teachers in Higher Education’ held 18–20 March 2010 in Bratislava with the participation of 20 international academics engaged in both teacher training and researching teaching and learning in higher education. One of the conclusions of the workshop was that directing attention to teaching in higher education is critical for the future of European higher education. Accordingly, this paper calls the attention of policy makers in Europe to the pressing need to improve the quality of teaching in higher education and makes recommendations at the European, national and institutional levels to achieve this

Grassy–herbaceous land moderates regional climate effects on honey bee colonies in the Northcentral US

The lack of seasonally sustained floral resources (i.e. pollen and nectar) is considered a primary global threat to pollinator health. However, the ability to predict the abundance of flowering resources for pollinators based upon climate, weather, and land cover is difficult due to insufficient monitoring over adequate spatial and temporal scales. Here we use spatiotemporally distributed honey bee hive scales that continuously measure hive weights as a standardized method to assess nectar intake. We analyze late summer colony weight gain as the response variable in a random forest regression model to determine the importance of climate, weather, and land cover on honey bee colony productivity. Our random forest model predicted resource acquisition by honey bee colonies with 71% accuracy, highlighting the detrimental effects of warm, wet regions in the Northcentral United States on nectar intake, as well as the detrimental effect of years with high growing degree day accumulation. Our model also predicted that grassy–herbaceous natural land had a positive effect on the summer nectar flow and that large areas of natural grassy–herbaceous land around apiaries can moderate the detrimental effects of warm, wet climates. These patterns characterize multi-scale ecological processes that constrain the quantity and quality of pollinator nutritional resources. That is, broad climate conditions constrain regional floral communities, while land use and weather act to further modify the quantity and quality of pollinator nutritional resources. Observing such broad-scale trends demonstrates the potential for utilizing hive scales to monitor the effects of climate change on landscape-level floral resources for pollinators. The interaction of climate and land use also present an opportunity to manage for climate-resilient landscapes that support pollinators through abundant floral resources under climate change

Variance in heat tolerance in bumble bees correlates with species geographic range and is associated with several environmental and biological factors

Abstract Globally, insects have been impacted by climate change, with bumble bees in particular showing range shifts and declining species diversity with global warming. This suggests heat tolerance is a likely factor limiting the distribution and success of these bees. Studies have shown high intraspecific variance in bumble bee thermal tolerance, suggesting biological and environmental factors may be impacting heat resilience. Understanding these factors is important for assessing vulnerability and finding environmental solutions to mitigate effects of climate change. In this study, we assess whether geographic range variation in bumble bees in the eastern United States is associated with heat tolerance and further dissect which other biological and environmental factors explain variation in heat sensitivity in these bees. We examine heat tolerance by caste, sex, and rearing condition (wild/lab) across six eastern US bumble bee species, and assess the role of age, reproductive status, body size, and interactive effects of humidity and temperature on thermal tolerance in Bombus impatiens. We found marked differences in heat tolerance by species that correlate with each species' latitudinal range, habitat, and climatic niche, and we found significant variation in thermal sensitivity by caste and sex. Queens had considerably lower heat tolerance than workers and males, with greater tolerance when queens would first be leaving their natal nest, and lower tolerance after ovary activation. Wild bees tended to have higher heat tolerance than lab reared bees, and body size was associated with heat tolerance only in wild‐caught foragers. Humidity showed a strong interaction with heat effects, pointing to the need to regulate relative humidity in thermal assays and consider its role in nature. Altogether, we found most tested biological conditions impact thermal tolerance and highlight the stages of these bees that will be most sensitive to future climate change