Determinants of male territorial behavior in a Hungarian collared flycatcher population: plumage traits of residents and challengers

In intrasexual conflicts, contestants can rely on relative or absolute size of status badges to mediate aggressive behavior. Most studies focus on the response of focal animals to variation in status badges of their competitors; few have simultaneously considered the traits of both participants under experimental conditions. By simulating territorial intrusions, we tested the importance of two sexual traits [forehead patch size (FPS) and wing patch size (WPS)] in territorial behavior of males in a Hungarian population of the collared flycatcher, Ficedula albicollis. We presented a stimulus male to an unpaired resident male to examine whether the characteristics of the territory owner or those of the challenger were associated with the latency of the first attack of the owner, which is a good predictor of the territorial behavior in general. WPS of the stimulus male was a significant determinant of the latency of the first attack, as males with a larger WPS elicited quicker attacks from the residents than males with a small WPS. From the residents’ perspective, age appeared to influence their territorial behavior, as yearlings had shorter attack latencies than older males. Additionally, latency could be considered an individual-specific attribute because it varied consistently among males, even when the WPS of the stimulus male was controlled, and it was associated with pairing success. Contrary to findings in a Swedish population, FPS seemed to be unimportant in male–male competition in our population, which suggests population differences in the role of the two plumage traits. Our results indicate that in a territorial conflict, the characteristics of both participants are important.     

The relationship between maternal ornamentation and feeding rate is explained by intrinsic nestling quality

In altricial birds, parental feeding is essential, and its amount may depend on the quality of both parents. A relationship between parental quality and feeding rate is generally attributed to an active adjustment by parents in order to retain good quality mates or ensure high fitness through raising high-quality offspring. However, the behaviour and need of young may also change with parental quality, and this may affect parental behaviour. A further problem is that most studies have investigated post-hatching parental investment in relation to the secondary sexual signals of males, but not females. In a cross-fostering experiment, we examined the feeding rates of rearing parents in relation to the size and ornamentation of both original and rearing parents in collared flycatchers (Ficedula albicollis). Using this setup, we could examine whether the observed feeding patterns were the results of the decision of the parents based on their own and their partner’s traits or the constraints imposed by the behaviour or need of offspring. When correcting for clutch size and year, we found that feeding rate of both foster parents correlated with the wing patch size of the original female. This implies that original maternal quality had an offspring-mediated indirect effect on investment of foster parents, that is intrinsic nestling quality may constrain parental feeding decisions. This explanation should not be overlooked in future studies on preferential parental investment, and our results also point out that maternal ornaments deserve more attention in such studies.     

Using decision science to evaluate global biodiversity indices

Global biodiversity indices are used to measure environmental change and progress toward conservation goals, yet few indices have been evaluated comprehensively for their capacity to detect trends of interest, such as declines in threatened species or ecosystem function. Using a structured approach based on decision science, we qualitatively evaluated 9 indices commonly used to track biodiversity at global and regional scales against 5 criteria relating to objectives, design, behavior, incorporation of uncertainty, and constraints (e.g., costs and data availability). Evaluation was based on reference literature for indices available at the time of assessment. We identified 4 key gaps in indices assessed: pathways to achieving goals (means objectives) were not always clear or relevant to desired outcomes (fundamental objectives); index testing and understanding of expected behavior was often lacking; uncertainty was seldom acknowledged or accounted for; and costs of implementation were seldom considered. These gaps may render indices inadequate in certain decision-making contexts and are problematic for indices linked with biodiversity targets and sustainability goals. Ensuring that index objectives are clear and their design is underpinned by a model of relevant processes are crucial in addressing the gaps identified by our assessment. Uptake and productive use of indices will be improved if index performance is tested rigorously and assumptions and uncertainties are clearly communicated to end users. This will increase index accuracy and value in tracking biodiversity change and supporting national and global policy decisions, such as the post-2020 global biodiversity framework of the Convention on Biological Diversity.     

The impact of career customization on work outcomes: Boundary conditions of manager support and employee age

The current paper investigated the longitudinal effects of mass career customization (MCC) on job attitudes and objective career outcomes of employees in a professional service firm in the Netherlands. On the basis of theory on individualization of career trajectories, it was expected that the possibility for employees to customize their careers would be positively related to their job attitudes and subsequent objective career success, as indicated by their levels of affective commitment, work engagement, and received salary and bonuses. However, these effects were expected to occur primarily under the combination of high manager support for implementation of career customization and, on the basis of lifespan theory, older workers, as customization fulfills their increased heterogeneous career preferences. A three‐wave longitudinal study largely showed support for the study hypotheses; the relation between MCC use and work engagement and subsequent career success was stronger for older workers who received support for MCC, whereas the relation between MCC use and commitment was negative for older workers who received low support. The study shows the benefits of career customization in organizations by showing the conditions under which these benefits will manifest. Copyright © 2015 John Wiley & Sons, Ltd.     

Conceptual development of a harmonised method for tracking change and evaluating policy in the agri-environment: The Agri-environmental Footprint Index

An aggregated farm-level index, the Agri-environmental Footprint Index (AFI), based on multiple criteria methods and representing a harmonised approach to evaluation of EU agri-environmental schemes is described. The Index uses a common framework for the design and evaluation of policy that can be customised to locally relevant agri-environmental issues and circumstances. Evaluation can be strictly policy-focused, or broader and more holistic in that context-relevant assessment criteria that are not necessarily considered in the evaluated policy can nevertheless be incorporated. The Index structure is flexible, and can respond to diverse local needs. The process of Index construction is interactive, engaging farmers and other relevant stakeholders in a transparent decision-making process that can ensure acceptance of the outcome, help to forge an improved understanding of local agri-environmental priorities and potentially increase awareness of the critical role of farmers in environmental management. The structure of the AFI facilitates post-evaluation analysis of relative performance in different dimensions of the agri-environment, permitting identification of current strengths and weaknesses, and enabling future improvement in policy design. Quantification of the environmental impact of agriculture beyond the stated aims of policy using an ‘unweighted’ form of the AFI has potential as the basis of an ongoing system of environmental audit within a specified agricultural context.     

The Potential of Soil Carbon Sequestration Through Improved Management Practices in Norway

The study was conducted to assess the potential of Norwegian agricultural ecosystems to sequester carbon (C) based on the data from some long-term agronomic and land use experiments. The total emission of CO₂ in Norway in 1998 was 41.4 million metric ton (MMT), of which agriculture contributed only 0.157 MMT, or <0.4% of the total emissions. With regards to methane (CH₄) and nitrous oxide (N₂O) gases, however, agricultural activities contributed 32.5% and 51.3% of their respective emissions in Norway. The soil organic carbon (SOC) losses associated with accelerated soil erosion in Norway are estimated at 0.475 MMTC yr^–1. Land use changes and soil/crop management practices with potential for SOC sequestration include conservation tillage methods, judicious use of fertilizers and manures, use of crop residues, diverse crop rotations, and erosion control measures. The potential for SOC sequestration is 0.146 MMTC yr^–1 for adopting conservation tillage, 0.011–0.035 MMTC yr^–1 for crop residue management, 0.026 MMTC yr^–1 for judicious use of mineral fertilizer, 0.016–0.135 MMTC yr^–1 for manure application, and 0.036 MMTC yr^–1 for adopting crop rotations. The overall potential of these practices for SOC sequestration ranges from 0.591 to 1.022 MMTC yr^–1 with an average value of 0.806 MMTC yr^–1. Of the total potential, 59% is due to adoption of erosion control measures, 5.8% to restoration of peat lands, 21% to conversion to conservation tillage and residue management, and 14% to adoption of improved cropping systems. Enhancing SOC sequestration and improving soil quality, through adoption of judicious land use and improved system of soil and crop management, are prudent strategies for sustainable management of soil, water and environment resources.Readers should send their comments on this paper to: bhaskarn ath@aol.com within 3 months of publication of this issue.     

Contradictory results in sex ratio studies: populations do not necessarily differ

In avian sex ratio studies, results often differ between species and between populations within species. Some researchers argued that positive results were simply statistical artefacts and that sex ratio adjustment did not exist. However, many of the proposed mechanisms of sex ratio adjustment result in costly laying gaps. In these cases, females laying large clutches may restrict the sex manipulation to the first egg of the clutch. Consequently, detectability of sex ratio adjustment on the level of the clutch can be low. Though obvious, this fact is often neglected in the literature. Using simulations, I show that the proportion of undetected sex manipulation can be surprisingly high when the manipulation is restricted to the first egg. If the sample size is 50 broods, there is 47% and 71% chance in 6- and 12-egg clutches, respectively, that sex manipulation is undetected. Even with large samples (n = 100), the figures are 15% and 46%. These data suggest that nonsignificant results for clutch sex ratios do not necessarily mean that sex is not manipulated in a portion of the brood, e.g. in first-laid eggs. Hence, whenever possible, data on laying order-specific sex manipulation should also be collected. Without such data, contradictory results on brood sex ratios should be interpreted cautiously.     

Positive polarotaxis in a mayfly that never leaves the water surface: polarotactic water detection in Palingenia longicauda (Ephemeroptera)

Tisza mayflies, Palingenia longicauda (Olivier 1791), swarm exclusively over the river Tisza (from which the name of the mayfly was derived). This river is bordered by a high vertical wall of trees and bushes, which hinder P. longicauda to move away horizontally from the water. During swarming, Tisza mayflies fly immediately above the river in such a way that their cerci touch the water frequently or sweep its surface. This continuous close connection with water and the vertical wall of the shore and riparian vegetation result in that Tisza mayflies never leave the water surface; consequently, they need not search for water. Several Ephemeroptera species move away far from water and return to it guided by the horizontal polarization of water-reflected light. To reveal whether also P. longicauda is or is not polarotactic, we performed a field experiment during the very short swarming period of Tisza mayflies. We show here that also P. longicauda has positive polarotaxis, which, however, can be observed only under unnatural conditions, when the animals are displaced from the water and then released above artificial test surfaces. P. longicauda is the first species in which polarotactic water detection is demonstrated albeit it never leaves the water surface, and thus, a polarotactic water detection seems unnecessary for it. The polarotactic behaviour of Tisza mayflies explains the earlier observation that these insects swarm above wet asphalt roads running next to river Tisza.     

Erratum to: Elephants Also Like Coffee: Trends and Drivers of Human–Elephant Conflicts in Coffee Agroforestry Landscapes of Kodagu,Western Ghats,India

Kodagu district produces 2% of the world’s coffee, in complex, multistoried agroforestry systems. The forests of the district harbour a large population of the Asian elephant (Elephas maximus). The combined effects of high elephant density and major landscape changes due to the expansion of coffee cultivation are the cause of human–elephant conflicts (HEC). Mitigation strategies, including electric fences and compensation schemes implemented by the Forest Department have met with limited success. Building on previous studies in the area, we assessed current spatial and temporal trends of conflict, analysed local stakeholders’ perceptions and identified factors driving elephants into the estates. Our study, initiated in May 2007, shows that the intensity of HEC has increased over the last 10 years, exhibiting new seasonal patterns. Conflict maps and the lack of correlation between physical features of the coffee plantations and elephant visits suggest elephants move along corridors between the eastern and western forests of the district, opportunistically foraging when crossing the plantations. Dung analyses indicate elephants have selectively included ripe coffee berries in their diet. This is, to our knowledge, the first report of wild elephants feeding on coffee berries. If this new behaviour spreads through the population, it will compound an already severe conflict situation. The behavioural plasticity, the multiplicity of stakeholders involved, the difficulty in defining the problem and the limits of technical solutions already proposed suggest that HEC in Kodagu has the ingredients of a “wicked” problem whose resolution will require more shared understanding and problem solving work amongst the stakeholders.