Intraguild predation by <Emphasis Type="Italic">Harmonia axyridis</Emphasis> on coccinellids revealed by exogenous alkaloid sequestration

Summary.  Under laboratory conditions, the multicolored Asian lady beetle, Harmonia axyridis is well known as an intraguild predator of other ladybirds. However the real impact of this exotic species on native species was poorly investigated in the field. Because many ladybird species produce alkaloids as defensive compounds, we propose here a new method of intraguild predation monitoring in coccinellids based on alkaloid quantification by GC-MS. In laboratory experiments, adaline was unambiguously detected in fourth instar larvae of H. axyridis having ingested one egg or one first instar larva of Adalia bipunctata. Although prey alkaloids in the predator decreased with time, traces were still detected in pupae, exuviae and imagines of H. axyridis having ingested one prey when they were fourth instar larvae. Analysis of H. axyridis larvae collected in two potato fields shows for the first time in Europe the presence of exogenous alkaloids in 9 out of 28 individuals tested. This new method of intraguild predation detection could be used more widely to follow the interactions between predators and potential chemically defended insect preys.     

Cryptic prey colouration increases search time in brown trout (<Emphasis Type="Italic">Salmo trutta</Emphasis>): effects of learning and body size

Little is known about how cryptic colouration influences prey search in near-surface aquatic habitats, although such knowledge is critical for understanding the adaptive value of colour crypsis as well as the perceptive constraints influencing foraging behaviour in these environments. This study had two main aims: (1) to investigate how background colour matching by prey affects foraging efficiency by brown trout parr and (2) to investigate how foraging ability on cryptic and conspicuous prey is affected by fish size at age (reflecting dominance). We addressed these questions by training wild brown trout parr to forage individually on live brown-coloured maggots on a cryptic (brown) or conspicuous (green) background. A separate experiment confirmed the absence of trout preference for brown or green substrate. The results show that prey background colour matching increases search time in brown trout. Search time generally decreased by learning, but conspicuous prey remained an easier prey to find throughout the six training trials. Thus, perceptive constraints appear to limit search efficiency for cryptic prey, suggesting that cryptic colouration can confer survival benefits to prey in natural environments. Smaller fish generally found conspicuous prey faster than larger individuals, whereas search time for cryptic prey was not influenced by body size. This suggests that smaller individuals compensate for inferior competitive ability by increasing foraging activity rather than improving cognitive ability. The technique of varying cognitive demands in behavioural tasks could be used more in future studies aimed at distinguishing motivational effects from cognitive explanations for variation in behavioural performance.     

Social information use is a process across time, space, and ecology, reaching heterospecifics

Decision making can be facilitated by observing other individuals faced with the same or similar problem, and recent research suggests that this social information use is a widespread phenomenon. Implications of this are diverse and profound: for example, social information use may trigger cultural evolution, affect distribution and dispersal of populations, and involve intriguing cognitive traits. We emphasize here that social information use is a process consisting of the scenes of (1) event, (2) observation, (3) decision, and (4) consequence, where the initial event is a scene in such a process of another individual. This helps to construct a sound conceptual framework for measuring and studying social information use. Importantly, the potential value of social information is affected by the distance in time, space, and ecology between the initial observation and eventual consequence of a decision. Because negative interactions between individuals (such as direct and apparent competition) also depend on the distance between individuals along these dimensions, the potential value of information and the negative interactions may form a trade-off situation. Optimal solutions to this trade-off can result in adaptively extended social information use, where using information gathered some time ago, some distance away, and from ecologically different individuals is preferred. Conceivably, using information gathered from a heterospecific individual might often be optimal. Many recent studies demonstrate that social information use does occur between species, and the first review of published cases is provided here. Such interaction between species, especially in habitat selection, has important consequences for community ecology and conservation. Adaptively extended social information use may also be an important evolutionary force in guild formation. Complex coevolutionary patterns may result depending on the effect of information use on the provider of information.     

Humanpharmakawirkstoffe in der Umwelt: Einträge, Vorkommen und der Versuch einer Bestandsaufnahme

Background

The presence of a large spectrum of pharmaceutical agents has been reported for aquatic environments (surface—and groundwater) and other aquatic media (influents and effluents of sewage treatment plants) in Germany and beyond, including their occurrence in drinking water. Considering the large number of pharmaceuticals produced for human use and released into the environment, various authors (Sattelberger 1999, Hanisch et al. 2004, Castiglioni et al. 2006, IWW 2006, Stockholm County Council 2006) tried to compile ‘priority lists’ focusing on those substances with environmental relevance. The following agents are included in all lists: ciprofloxacine, clarythromycine (antibiotics), carbamazepine (anti-epileptic agent), bezafibrate (lipid reducer), clofibric acid (lipid reducer metabolite), ethinylestradiol (sex hormone) and cylophosfamide (cytostatic agent). The agents erythromycine and sulfamethoxazole (antibiotics), ibuprofen, indometacine, propyphenazone (analgesics), atenolol (beta-blocker) and ifosfamide (cytostatic agent) can be found in three of four priority lists.

Results

Pharmaceuticals mainly enter the aquatic environment via effluent water, coming from wastewater treatment plants (including hospital and household sewerage), untreated discharges (e.g, secondary transfer of active agents into ground- and surface waters via sewage sludge application in agriculture and via landfill leachate) and leakages in the municipal sewer network.

Discussion

Potential activities towards a reduced release of pharmaceuticals into the environment should consider primarily the origin of the exposure to allow a separation of drug containing flows already at the source. Following the latter it would be possible to minimize the contamination of spring-, ground- and surface waters which serve as raw water resources for drinking water supply. However, considering the actual water pollution with pharmaceuticals and other substances, ‘end-of pipe’ techniques in the sewage and drinking water treatment are absolutely essential.

Conclusions

Sustainability criteria (e.g. protection of drinking water resources, habitats and biocoenoses, recycling and economizing use of resources) and economic aspects of modern sewage disposal concepts require a useful choice and combination of technical measures as components of centralized and decentralized sewage and drinking water treatment methods. It is though not realistic to cover and eliminate all pharmaceutical agents of environmental relevance equally effective even if a catalogue of potential technical treatment methods is elaborated thoroughly. Therefore, a concentration of efforts on selected drug agents, at least following initially some of the priority lists, is recommended.

Recommendations and Perspectives

The contamination of the water cycle with pharmaceuticals is nevertheless not exclusively to be solved via the application of technical methods. The BMBF (Federal Ministry for Education and Research) funded project start (Management Strategies for Pharmaceuticals in Drinking Water, www.start-project.de) therefore tries by implementation of a transdisciplinary approach to integrate technical-, behavioral-, and agent-orientated management strategies towards a more comprehensive and sustainable problem solution.     

Medikamentenentsorgung in privaten Haushalten: Ein Faktor bei der Gewässerbelastung mit Arzneimittelwirkstoffen?

Background

Residues of pharmaceuticals are meanwhile detected widely in the aquatic environment. Waste water treatment plants are the main route of entry: after intake the agents or their metabolites are excreted predominantly via urine into the sewage. Largely unknown is, however, if the improper disposal of unused medicines via domestic sanitary devices (toilet or sink) contributes to the measured concentrations in the environment. Aim of this investigation was to clarify to what extent consumers in Germany dispose of unused medicines directly via domestic sewage. In July and August 2006 a representative survey of the population with 2.000 interviewees was performed for this purpose.

Results

The analysis of the survey shows that the disposal of unused medicines via domestic sewage takes place on relevant scales: approx. 16% of the population dispose at least occasionally of unused or expired tablets in the toilet whereas 43% proceed alike with liquid drugs (toilet or sink).

Discussion

A possible reason for this disposal behaviour is the widely inconsistent waste disposal communication by the municipalities and the federal states. The resulting uncertainty about the correct way to dispose of unused medicines gains in importance in the context of the high recycling willingness of the (German) population: appropriate disposal options for drug residues (tablets or liquids) arising from waste separation are often not realised.

Conclusions

Quantitative assessments on the basis of the collected data demonstrate that the established frequency of direct disposal of unused medicines via domestic sewage can partly contribute significantly to the occurrence of pharmaceuticals in the aquatic environment. Crucial parameters are here the excretion rate of the active pharmaceutical ingredient considered and the actual amount of medication waste.

Recommendations

Based on the inquiry results, measures that lead to a more adequate handling of pharmaceutical waste disposal are demanded. The establishment of a consistent and binding disposal standard for unused medicines via return in pharmacies is recommended. This measure needs to be accompanied by a simplification of the established take back systems which partly cause high time and effort for pharmacies.     

Alnus shrub expansion increases evapotranspiration in the Swiss Alps

Regional Environmental Change - Shrub encroachment is one of the main consequences of abandonment of montane grassland. Higher surface roughness of shrubs leads to stronger aerodynamic coupling....     

Air pollution inhalation during acute exercise is dependent of the body mass index and ventilation of young men

Environmental Science and Pollution Research - Obesity and physical inactivity threaten human health, and both could be solved with exercise. However, a higher amount of pollutants is inhaled...     

Identifying key needs for the integration of social–ecological outcomes in arctic wildlife monitoring

For effective monitoring in social–ecological systems to meet needs for biodiversity, science, and humans, desired outcomes must be clearly defined and routes from direct to derived outcomes understood. The Arctic is undergoing rapid climatic, ecological, social, and economic changes and requires effective wildlife monitoring to meet diverse stakeholder needs. To identify stakeholder priorities concerning desired outcomes of arctic wildlife monitoring, we conducted in-depth interviews with 29 arctic scientists, policy and decision makers, and representatives of indigenous organizations and nongovernmental organizations. Using qualitative content analysis, we identified and defined desired outcomes and documented links between outcomes. Using network analysis, we investigated the structure of perceived links between desired outcomes. We identified 18 desired outcomes from monitoring and classified them as either driven by monitoring information, monitoring process, or a combination of both. Highly cited outcomes were make decisions, conserve, detect change, disseminate, and secure food. These reflect key foci of arctic monitoring. Infrequently cited outcomes (e.g., govern) were emerging themes. Three modules comprised our outcome network. The modularity highlighted the low strength of perceived links between outcomes that were primarily information driven or more derived (e.g., detect change, make decisions, conserve, or secure food) and outcomes that were primarily process driven or more derived (e.g., cooperate, learn, educate). The outcomes expand monitoring community and disseminate created connections between these modules. Key desired outcomes are widely applicable to social–ecological systems within and outside the Arctic, particularly those with wildlife subsistence economies. Attributes and motivations associated with outcomes can guide development of integrated monitoring goals for biodiversity conservation and human needs. Our results demonstrated the disconnect between information- and process-driven goals and how expansion of the monitoring community and improved integration of monitoring stakeholders will help connect information- and process-derived outcomes for effective ecosystem stewardship.     

A novel multi-model data-driven ensemble approach for the prediction of particulate matter concentration

Environmental Science and Pollution Research - Accuracy in the prediction of the particulate matter (PM2.5 and PM10) concentration in the atmosphere is essential for both its monitoring and...