The anti-predator function of ‘eyespots’ on camouflaged and conspicuous prey

Animals utilise various strategies to reduce the risk of predation, including camouflage, warning colours and mimicry, and many of these protective signals promote avoidance behaviour in predators. For example, various species possess paired circular ‘eyespots’, which startle or intimidate predators, preventing or halting an attack. However, little is known of how the efficacy of such signals relates to the context in which they are found, and no studies have tested the relative effectiveness of anti-predator signals when on otherwise camouflaged and conspicuous prey. We find that the protective value of conspicuous wing spots, placed on artificial moth-like targets presented to wild birds in the field, is strongly affected by the attributes of the prey ‘animal’ on which they are found. Wing spots reduced predation when on conspicuous prey but were rendered ineffective when on otherwise camouflaged targets, indeed they increased the risk of predation compared to non-marked camouflaged controls. These results demonstrate how different anti-predator strategies may interact, and that protective signals can switch from being beneficial to costly under different contexts.     

Nutrient pathways and their susceptibility to past and future change in the Eurasian Arctic Ocean

Climate change is altering nutrient cycling within the Arctic Ocean, having knock-on effects to Arctic ecosystems. Primary production in the Arctic is principally nitrogen-limited, particularly in the western Pacific-dominated regions where denitrification exacerbates nitrogen loss. The nutrient status of the eastern Eurasian Arctic remains under debate. In the Barents Sea, primary production has increased by 88% since 1998. To support this rapid increase in productivity, either the standing stock of nutrients has been depleted, or the external nutrient supply has increased. Atlantic water inflow, enhanced mixing, benthic nitrogen cycling, and land–ocean interaction have the potential to alter the nutrient supply through addition, dilution or removal. Here we use new datasets from the Changing Arctic Ocean program alongside historical datasets to assess how nitrate and phosphate concentrations may be changing in response to these processes. We highlight how nutrient dynamics may continue to change, why this is important for regional and international policy-making and suggest relevant research priorities for the future.Supplementary InformationThe online version contains supplementary material available at 10.1007/s13280-021-01673-0.     

Effectiveness of Management Interventions to Control Invasion by Rhododendron ponticum

Rhododendron ponticum is an invasive species in many countries, including the United Kingdom, Ireland, Belgium, and France. It poses a serious threat to native flora and fauna, as it is capable of altering entire seminatural communities through its vigorous spread. Control is essential if the conservation value of some communities, such as oak woodland and lowland heath, are to be successfully maintained. Commonly used interventions are herbicide application, herbicide application postcut, and cutting (manual or mechanical) alone. Various techniques have been developed to apply these interventions, but often retreatment of the area is required, increasing the cost of control. Here, we evaluate the effectiveness of some commonly used interventions for R. ponticum control using a systematic review methodology. Eleven studies provided data for statistical analysis. Meta-analyses of captured data show that postcut application of the herbicide Glyphosate or applying the herbicides Metsulfuron-methyl or Imazapyr (no cut) can effectively reduce a R. ponticum stand. There is insufficient available experimental evidence for effectiveness of any other intervention. The systematic review process has demonstrated the lack of replicated studies with controls or long-term monitoring and increases the call for more rigorous monitoring of all conservation management interventions. The quality of experimental evidence of the effectiveness of some interventions contrasts with the acceptance of their use through dissemination of experience. The collection and objective review of experience will require active collaboration of organizations concerned with R. ponticum control.     

A scoping review into the impact of animal imagery on pro-environmental outcomes

With the recognition that most global environmental problems are a result of human actions, there is an increasing interest in approaches which have the potential to influence human behaviour. Images have a powerful role in shaping persuasive messages, yet research on the impacts of visual representations of nature is a neglected area in biodiversity conservation. We systematically screened existing studies on the use of animal imagery in conservation, identifying 37 articles. Although there is clear evidence that images of animals can have positive effects on people’s attitudes to animals, overall there is currently a dearth of accessible and comparable published data demonstrating the efficacy of animal imagery. Most existing studies are place and context-specific, limiting the generalisable conclusions that can be drawn. Transdisciplinary research is needed to develop a robust understanding of the contextual and cultural factors that affect how animal images can be used effectively for conservation purposes.

     

Mapping the public first-aid training landscape: a scoping review

While the public can play a vital role in saving lives during emergencies, intervention is only effective if people have the skills, confidence, and willingness to help. This review employs a five-stage framework to systematically analyse first aid and emergency helping literature from 22 countries (predominately in Asia, Australia, Europe, and the United States). The review covers 54 articles that investigate public first-aid knowledge and uptake of first-aid training (40); public confidence in first-aid skills and willingness to help during an emergency (21); and barriers to or enablers of learning first aid and delivering first aid in an emergency (25). The findings identify high levels of perceived knowledge, confidence, and willingness to help, supporting the contention that the public can play a vital role during an emergency. However, the findings also point to low uptake levels, low tested skill-specific knowledge, and barriers to learning first aid and helping, indicating that the first-aid training landscape is in need of improvement.     

Differential livelihood adaptation to social-ecological change in coastal Bangladesh

Regional Environmental Change - Social-ecological changes, brought about by the rapid growth of the aquaculture industry and the increased occurrence of climatic stressors, have significantly...     

Variation of raw wastewater microbiological quality in dry and wet weather conditions

The microbiological quality of urban wastewaters presents important environmental, sanitary, and political challenges. However, the variability of untreated wastewater quality is seldom known when it comes to microbial parameters. This study aims to evaluate the variability of microbiological quality in wastewater influents from different wastewater treatment plants connected to combined and partially separate sewer networks in the Parisian area and to evaluate the impact of this variability on the treatment efficiency and on the accuracy of wastewater effluent monitoring. The densities of fecal indicator bacteria (FIB), Escherichia coli and intestinal enterococci, and their partitioning on settleable particles were analyzed at the inlet of two wastewater treatment plants during dry weather (130 composite samples and 7 days sampled every 2 hours) and storm events (39 composite samples, and 7 rain courses) from 2008 to 2012. The results showed that fecal indicator densities vary according to the network characteristics and according to the meteorological conditions. During storm events, a significant dilution of E. coli and enterococci was observed, as well as a decrease in the settleable fraction of E. coli during the maximal impact of the storm. However, storm events did not significantly impact the regular FIB monitoring. FIB removals by primary and secondary treatment were significantly correlated with FIB densities in influent wastewater; however, meteorological conditions also influenced the removal of FIB.     

Acid Particles and the Tracheobronchial Region of the Respiratory System—An “Irritation-Signaling” Model for Possible Health Effects

This paper explores some detailed mechanistic hypotheses for the possible action of acid particles on the tracheobronchial region of the human respiratory system. Because of the buffering capacity and volume of mucus produced per day it appears doubtful that ordinary ambient exposures to acid particles could markedly change the overall pH of tracheobronchial mucus considered as a whole. However it is possible that individual acidic particles could contain enough acid to deliver localized “irritant signals” that could be the triggers for enhanced mucus secretion and cell division in sensitive portions of the bronchial tree, and thereby contribute to the processes involved in chronic bronchitis.

Depending on the exact pH depression required for a “signal” to be perceived by the tracheobronchial epithelium, the acid content of the incoming particles per unit weight, and the effect of neutralization by ammonia in the upper respiratory tract, the minimum size of an acidic particle required to deliver a perceptible signal might range from about 0.4 to 0.7 microns for portions of the epithelium that are frequently swept by 4-micron mucus droplets. (For unprotected epithelium, however, it is conceivable that the minimum effective size for acid particles could be less.) Since particle number per unit weight declines dramatically with increasing particle size, the most potent fraction of particles in terms of signals delivered per μg/m³is likely to be just above the minimum size that is needed to produce an effective signal. The model developed here makes predictions of the relative potency of particles of different size and acid delivery capacity that could be tested in both experimental animal systems and human epidemiological studies.