Divergent selection stemming from environmental variation may induce local adaptation and ecological speciation whereas gene flow might have a homogenizing effect. Gene flow among populations using different environments can be reduced by geographical distance (isolation‐by‐distance) or by divergent selection stemming from resource use (isolation‐by‐ecology). We tested for and encountered phenotypic and genetic divergence among Spanish crossbills utilizing different species of co‐occurring pine trees as their food resource. Morphological, vocal and mtDNA divergence were not correlated with geographical distance, but they were correlated with differences in resource use. Resource diversity has now been found to repeatedly predict crossbill diversity. However, when resource use is not 100% differentiated, additional characters (morphological, vocal, genetic) must be used to uncover and validate hidden population structure. In general, this confirms that ecology drives adaptive divergence and limits neutral gene flow as the first steps towards ecological speciation, unprevented by a high potential for gene flow.

Aquaculture within offshore wind farms has been identified as one of the many possibilities of smart use of marine space, leading to opportunities for innovative entrepreneurship. Offshore areas potentially pose less conflict with co-users than onshore. At the same time, offshore areas and offshore constructions are prone to high technical risks through mechanical force, corrosion, and biofouling. The expected lifetime of an offshore structure is to a great extent determined by the risk of failures. This chapter elaborates on logistical challenges that the offshore industry faces. Operation and maintenance (O&M) activities typically represent a big part of the total costs (e.g. 25-30% of the total lifecycle costs for offshore wind farms). The offshore wind energy sector is considered an industry with promising features for the public and private sector. Large wind farms farther off the coast pose high expectations because of higher average wind speeds and hence greater wind energy yield (in terms of megawatts per capital). These conditions entail additional challenges in logistics, though. One of the main hurdles that hinders use of offshore wind energy is the high cost for O&M. The offshore wind industry will have to solve these problems in order to achieve substantial cost reduction -alone or jointly with other (potential) users. It is precisely the logistical problems around O&M where most likely synergy benefits of multi-use platforms (MUPs) can be achieved. The offshore wind energy industry is eagerly looking for technical innovations. Until now they mostly sought the solutions in their own circles. If the combination of offshore wind energy and offshore aquaculture proves to be feasible and profitable in practice, there may be an additional possibility to reduce the O&M costs by synergy effects of the combined operations. Logistic waiting times, for example, can result in substantial revenue losses, whereas timely spare-parts supply or sufficient repair capacity (technicians) to shorten the logistic delay times are beneficial. A recent study suggests that a cost reduction of 10% is

With a foreseen increase in maritime activities, and driven by new policies and conventions aiming at sustainable management of the marine ecosystem, spatial management at sea is of growing importance. Spatial management should ensure that the collective pressures caused by anthropogenic activities on the marine ecosystem are kept within acceptable levels. A multitude of approaches to environmental assessment are available to provide insight for sustainable management, and there is a need for a harmonized and integrated environmental assessment approach that can be used for different purposes and variable levels of detail. This article first provides an overview of the main types of environmental assessments: "environmental impact assessment" (EIA), "strategic environmental assessment" (SEA), "cumulative effect assessment" (CEA), and "environmental (or ecological) risk assessment" (ERA). Addressing the need for a conceptual "umbrella" for the fragmented approaches, a generic framework for environmental assessment is proposed: cumulative effects of offshore activities (CUMULEO). CUMULEO builds on the principle that activities cause pressures that may lead to adverse effects on the ecosystem. Basic elements and variables are defined that can be used consistently throughout sequential decision-making levels and diverse methodological implementations. This enables environmental assessment to start at a high strategic level (i.e., plan and/or program level), resulting in early environmental awareness and subsequently more informed, efficient, and focused project-level assessments, which has clear benefits for both industry and government. Its main strengths are simplicity, transparency, flexibility (allowing the use of both qualitative and quantitative data), and visualization, making it a powerful framework to support discussions with experts, stakeholders, and policymakers. Integr Environ Assess Manag 2016;12:632-642. © 2015 SETAC.

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Why and how new migration routes emerge remain fundamental questions in ecology, particularly in the context of current global changes. In its early stages, when few individuals are involved, the evolution of new migration routes can be easily confused with vagrancy, i.e. the occurrence of individuals outside their regular breeding, non-breeding or migratory distribution ranges. Yet, vagrancy can in theory generate new migration routes if vagrants survive, return to their breeding grounds and transfer their new migration route to their offspring, thus increasing a new migratory phenotype in the population. Here, we review the conceptual framework and empirical challenges of distinguishing regular migration from vagrancy in small obligate migratory passerines and explain how this can inform our understanding of migration evolution. For this purpose, we use the Yellow-browed Warbler (Phylloscopus inornatus) as a case study. This Siberian species normally winters in southern Asia and its recent increase in occurrence in Western Europe has become a prominent evolutionary puzzle. We first review and discuss available evidence suggesting that the species is still mostly a vagrant in Western Europe but might be establishing a new migration route initiated by vagrants. We then list possible empirical approaches to check if some individuals really undertake regular migratory movements between Western Europe and Siberia, which would make this species an ideal model for studying the links between vagrancy and the emergence of new migratory routes.

Bats regularly migrate over the North Sea, but information on the environmental conditions when this occurs is scarce. Detailed information is urgently needed on the conditions under which bats can be expected offshore, as the number of offshore windfarms that can cause fatalities amongst bats in the North Sea is increasing rapidly. We performed ultrasonic acoustic monitoring at multiple nearshore locations at sea between 2012 and 2016 for, in total, 480 monitoring nights. We modelled the offshore occurrence of Nathusius’ pipistrelle in autumn as a function of weather conditions, seasonality, and the lunar cycle using a generalized additive mixed model (GAMM). We investigated which covariates are important using backward selection based on a likelihood ratio test. Our model showed that important explanatory variables for the offshore occurrence of Nathusius’ pipistrelle are seasonality (night in year), wind speed, wind direction, and temperature. The species’ migration is strongest in early September, with east-northeasterly tailwinds, wind speeds < 5 m/s, and temperatures > 15 °C. Lunar cycle, cloud cover, atmospheric pressure, atmospheric pressure change, rain, and visibility were excluded during the model selection. These results provide valuable input to reduce bat fatalities in offshore wind farms by taking mitigation measures.

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