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There is an urgent need to understand ecological responses of avian species to the rapidly expanding human footprint of conventional and renewable energy development in sagebrush and prairie ecosystems. The ferruginous hawk (Buteo regalis) and golden eagle (Aquila chrysaetos) are two sympatric raptors of conservation concern that occupy and flourish in the most intact sagebrush steppe region remaining in North America. To understand these species’ use of habitat relative to energy development, we built resource selection functions using a spatially representative sample of occupied nesting territories collected in 2010–2011 and remotely sensed environmental variables across an extensive study area (186,693 km2). We used the resulting predicted resource selection maps to evaluate spatial overlap between the nesting habitats of these sympatric raptor species, as well as overlap of predicted habitat with potential development of oil/gas and wind energy resources. Remotely sensed variables were very effective in modeling patterns of nest‐site selection based on fivefold cross‐validation (>0.93 Spearman‐rank correlation) and validation with an independent dataset of historical nests collected from 2000 to 2009. Topographic roughness and intermediate levels of spring precipitation were the strongest drivers of differences in habitat use between ferruginous hawks and golden eagles. We did not detect a strong signal of avoidance of energy infrastructure by either species at current levels of development and both nested closer than expected to gravel/dirt roads associated with oil and gas infrastructure. However, extensive overlap of nesting habitat more selected by ferruginous hawks and golden eagles with areas of actual and potential energy development suggests both species are at risk from future habitat fragmentation. Given that 80% of nests are> 1 km from oil/gas wells, we believe the density of energy‐related disturbance present during our study was insufficient to drive patterns of resource selection for ferruginous hawks when considered at broad spatial scales. However, it was beyond the scope of our study to predict long‐term, population‐level responses. We suggest rigorous monitoring of long‐term trends in occupancy, productivity, and distribution is warranted for populations of ferruginous hawk and golden eagle in sagebrush and prairie ecosystems exposed to increased energy development.

Many factors drive the organization of communities including environmental factors, dispersal abilities, and competition. In particular, ant communities have high levels of interspecific competition and dominance that may affect community assembly processes. We used a combination of surveys and nest supplementation experiments to examine effects of a dominant ground-nesting ant (Pheidole synanthropica) on (1) arboreal twig-nesting, (2) ground-foraging, and (3) coffee-foraging ant communities in coffee agroecosystems. We surveyed these communities in high-and low-density areas of P. synanthropica over 2 years. To test for effects on twig ant recruitment, we placed artificial nesting resources on coffee plants in areas with and without P. synanthropica. Thefirst sampling period revealed differences in ant species composition on the ground, in coffee plants, and artificial nests between high-and low-density sites of P. synanthropica. Highdensity sites also had significantly lower recruitment of twig ants and had species-specific effects on twig ant species. Prior to the second survey period, abundance of P. synanthropica declined in the high-density sites, such that P. synanthropica densities no longer differed. Subsequent sampling revealed no difference in total recruitment of twig ants to artificial nests between treatments. Likewise, surveys of ground and coffee ants no longer showed significant differences in community composition. The results from the first experimental period, followed by survey results after the decline in P. synanthropica densities suggest that dominant ants can drive community assembly via both recruitment and establishment of colonies within the community.

Antimicrobial peptides as part of the mammalian innate immune system target and remove major bacterial pathogens, often through irreversible damage of their cellular membranes. To explore the mechanism by which the important cathelicidin peptide LL-37 of the human innate immune system interacts with membranes, we performed biochemical, biophysical and structural studies. The crystal structure of LL-37 displays dimers of anti-parallel helices and the formation of amphipathic surfaces. Peptide-detergent interactions introduce remodeling of this structure after occupation of defined hydrophobic sites at the dimer interface. Furthermore, hydrophobic nests are shaped between dimer structures providing another scaffold enclosing detergents. Both scaffolds underline the potential of LL-37 to form defined peptide-lipid complexes in vivo . After adopting the activated peptide conformation LL-37 can polymerize and selectively extract bacterial lipids whereby the membrane is destabilized. The supramolecular fibril-like architectures formed in crystals can be reproduced in a peptide-lipid system after nanogold-labelled LL-37 interacted with lipid vesicles as followed by electron microscopy. We suggest that these supramolecular structures represent the LL-37-membrane active state. Collectively, our study provides new insights into the fascinating plasticity of LL-37 demonstrated at atomic resolution and opens the venue for LL-37-based molecules as novel antibiotics.

Predation shapes communities through consumptive and non‐consumptive effects. In the latter case, prey respond to perceived predation risk through proactive or reactive risk management strategies occurring at different spatial and temporal scales. The predator–prey space race and landscape of fear concepts are useful to better understand how predation risk affects prey behavioral decisions and distribution. We assessed predation risk effects in a terrestrial Arctic community, where the arctic fox is the main predator of ground‐nesting birds. Using high‐frequency GPS data, we estimated a predator activity landscape corresponding to fox space use patterns and validated with an artificial prey experiment that this predator activity landscape correlated with the predation risk landscape. We then investigated the effects of the fox activity landscape on multiple prey species, by assessing the anti‐predator behavior of a main prey (snow goose) actively searched for by foxes, and the nest distribution of several incidental prey species. We first found that snow geese showed a stronger level of nest defense in areas highly used by foxes, possibly responding with a reactive strategy to variation in predation risk. Then, nests of incidental prey reproducing in habitats easily accessed by foxes had a lower probability of occurrence in areas highly used by foxes, suggesting these birds may use a proactive risk management strategy by shifting their distribution away from risky areas. For incidental prey species nesting in microhabitat refuges difficult to access by foxes, probability of nest occurrence was independent of predation risk in the surrounding area, as they avoid risk at a finer spatial scale. By tracking all individuals of the dominant predator species in our study area, we demonstrated the value of using predator space use patterns to infer spatial variation in predation risk. Overall, we highlight the diversity of risk management strategies in prey sharing a common predator, hence refining our understanding of the mechanisms driving species distribution and community structure.

Constructed wetlands may compensate to some degree for the impact of the loss of natural wetlands on aquatic biodiversity. However, information is lacking on the relative value of artificial wetlands and comparable natural wetlands for freshwater turtles. I contrasted the population structure, diet and body growth of Australian eastern long-necked turtles (Chelodina longicollis) in artificial and natural ponds in farmland settings. Turtle populations in the artificial ponds had a more even distribution of body size, and a much larger proportion of young individuals, than those in the natural ponds, suggesting that the artificial ponds were important recruitment sites. Diet differed little between the two types of ponds, being greatly dominated by aquatic insects in both cases. However, body growth of juvenile turtles was on average more rapid in the artificial ponds, possibly because they were generally permanent, unlike the natural ponds. These findings suggest that artificial farm ponds are valuable habitats for C. longicollis, which may foster population recruitment that counters the effects of introduced nest predators and road mortality.

Nest predation is one of the most important causes of nest failure in breeding birds and can vary extensively between sites and years. Different mechanisms governing predation rates may dominate in different years and this annual variation should therefore be evaluated directly. Here we document year-to-year variation in nest predation rates in two ecosystems (forest and salt meadows) within the mid-boreal forest zone to evaluate whether annual variation in nest predation rates are linked with annual variation in predator identity or the ratio between predator types. Year-to-year variation in predation rates was low in all experiments (non-significant differences in experiments 1 and 2), with a significant decrease only from 2005 (0.90%) to 2008 (0.70%), 2009 (0.65%) and 2010 (0.72%) in experiment 3. In addition, random intercept estimates indicated that two sites from experiment 1 showed higher predation rates in year 2 than in year 1. None of these differences were related with differences in apparent predator community structure or predator identity. This suggests that low between-year variation in nest predation rates may be common in areas where the predator communities are stable, and the existing variation cannot be explained by variation in predator identity alone.

Evidence-based conservation allows the evaluation of both the collateral benefits and the drawbacks of a wide range of human activities, like quarrying. In this study, the community structure of bees and wasps (Hymenoptera:Apocrita) in Central European sandpits was investigated, focusing on the changes caused by quarrying cessation and technical reclamation, as well as on the changes caused by spontaneous succession leading to the increased availability of food resources but also to the loss of the number and size of available bare sand patches. The bees and wasps demonstrated an exceptional ability to colonize the newly emerging sand quarrying areas, and to survive in them unless these were quarried as intensively as to not allow the development of any early successional vegetation. Both active and closed sandpits were found to serve as important regional refuges for the persistence of many rare species. In total, 221 species were detected, 53 of those were red-listed, with two species thought to be regionally extinct. Typically, active quarrying was associated with the presence of Bembecinus tridens , Halictus subauratus , H. maculatus , and Andrena nigroaenea. The list of the species of conservation interest is provided, and so is the detailed analysis of the life-history traits of the species in relation to the presence of bare sand patches, vegetation cover, quarrying intensity, and time elapsed since the formation of each artificial habitat patch. Sandpits as refuges for xerothermophilous and psammophilous hymenopterans are usually completely and irreversibly lost if the current legislature enforcing the technical reclamation over spontaneous or assisted succession is applied in all or most of the post-mining areas.

Urban and artificial structures are increasingly added to the world's coasts during a time in which changing climate is forecast to drive shifts in naturally occurring habitats. We ask whether the role of artificial structures as marine habitats will increase in importance relative to their natural counterparts, particularly as natural habitats are negatively affected by ocean warming and acidification. To evaluate this model, we contrasted use of natural (kelp forest and turfing algae) and artificial habitat (plastic pierpiling) by a nest-building amphipod (Cymadusa pemptos) under current and future climate conditions of CO₂ and temperature. Under future conditions, amphipod populations in mesocosms increased, but this did not lead to greater proportional colonization of kelp and turf. Instead, colonization doubled in artificial habitats, and there was increasing production and occupation of nests on artificial habitats relative to natural habitats. In an age when human modification of natural substrata is increasingly cited as an agent of wildlife decline, understanding the future role of artificial habitats as replacement dwellings for natural habitats is critical. We pioneer an understanding of the future role of natural and artificial habitats, identifying the possibility that the role of urban structures as marine habitats may only increase.

Since the early 20th century, wildlife managers have deployed artificial nesting structures for wood ducks (Aix sponsa) to increase availability of nest sites and local reproduction of the species. However, knowledge is lacking of the effects of nest structure size (i.e., large vs. small; Stephens et al. 1998) and reproductive data (e.g., clutch size, hatch date, duckling survival) on recruitment of wood ducks. We used stochastic simulation analyses to predict recruitment of wood ducks into late summer by analyzing data from a 6-year study of box-nesting wood ducks, and 4-year (Mississippi) and 2-year (Alabama) studies of radio-marked female wood ducks and their ducklings. Our index of recruitment was the number of radio-marked ducklings per nest box that survived until 1 September. Ducklings hatched after 1 June exhibited a 30-day survival probability of 0.29, which was nearly 3 times greater than those hatched before 1 June. In east-central Mississippi, 68% and 65% of total wood duck recruits from large and small boxes, respectively, were hatched and reared from June to August. In western Mississippi, 91% of recruits from each box size also were hatched and reared from June to August. Mean number of wood duck recruits produced from large boxes was greater than small boxes at each study site; each large box in western Mississippi produced approximately 4 recruits on average, whereas small boxes in east-central Mississippi produced approximately 1 recruit. Wood duck recruits in our study resulted primarily from late spring and summer hatched birds in contrast to most Nearctic ducks with adaptive, early nesting to promote recruitment. In Mississippi and similar southern environments, we recommend use of large boxes and cleaning boxes around 1 May after completion of initial nests, and emphasize the importance of late spring and summer duckling production to wood duck recruitment.

Predation plays a critical role in animal and plant survivorship, and can be highly sensitive to habitat loss and disturbance. Tropical montane forests in Southeast Asia are being modified rapidly by land-use change, and the consequences of this on predation likelihood are poorly understood. In Peninsular Malaysia, we conducted predation experiments at eight tropical montane forest sites along a disturbance gradient. We investigated whether (1) predation pressure in primary forests differs between different mountains; (2) predation probability is linked to habitat degradation; and (3) vegetation variables explain predation occurrence. At each forest site, we placed artificial nests with real and model quail eggs, dishes with real and artificial seeds of the cempedak (Artocarpus champeden), models resembling four-lined tree frogs (Polypedetes leucomystax) and models of the late instar caterpillar of the common Mormon (Papilio polytes) at points 100 m apart for three nights. Using Bayesian binomial simulations, we showed that predation likelihood in primary forests from different mountains can vary (e.g., probability of the difference in predation rate of artificial caterpillars between two primary forests was estimated at 82–100%). We also found that higher predation was not linked to habitat degradation for all artificial prey and seeds (e.g., comparing forests of varying degrees of disturbance from the same mountain, the probability that predation of an artificial caterpillar is lower at the primary forest was estimated at 2–20% only). Model selection and hierarchical partitioning showed that vegetation variables can explain predation occurrence, suggesting microhabitat characteristics may be influential. Conducting predation experiments by using artificial prey and seeds is useful for comparing predation likelihood at different sites, making ecological comparisons, and for informing conservation decisions. This novel approach of using multiple prey items also showed that predation for each can vary and thus caution against deploying a single prey type to draw broad inferences of predation in degraded systems.