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1. Restoration is increasingly undertaken to ameliorate the risks of habitat loss and transformation to biodiversity. Despite significant expenditure of time and resources world-wide, restored habitats commonly fail to achieve these objectives. 2. Restoration could fail because animals either avoid restored habitats (perceptual traps) or prefer restored habitats where their fitness is reduced (ecological traps). Consequently, restoration may have a neutral impact or more worryingly provide an additional risk to population persistence. Whether traps arise as an unintended consequence of restoration has largely been unexplored. 3. Our aim is to highlight how traps can compromise restoration efforts and propose ways to reduce this possibility. We first highlight five criteria for successful habitat restoration to identify how and where ecological and perceptual traps could arise and use case studies to demonstrate some of the diverse ways restoration could cause traps. Managing traps that form via restoration depends on reinstating the links between habitat quality and preference. We suggest resource-based habitat approaches, which consider what represents functional habitats from the perspective of animals, are a potentially useful tool in this regard. Furthermore, cognitive theory may help to improve our understanding of how animals select habitats and to address problematic behaviours as they arise. 4. Synthesis and applications. Restoration will fail if habitat quality and preference are not strongly linked, but this possibility has received limited attention. Our review will help ensure that restored habitats provide the resources required by animals, and that animals assess and respond to these habitats adaptively. We hope to stimulate further discussion between evolutionary, behavioural and restoration ecologists to improve the success of habitat restoration.

Divergent movement strategies have enabled wildlife populations to adapt to environmental change. In recent decades, the Southern Beaufort Sea subpopulation of polar bears (Ursus maritimus) has developed a divergent movement strategy in response to diminishing sea ice where the majority of the subpopulation (73–85%) stays on the sea ice in summer and the remaining bears move to land. Although declines in sea ice are generally considered a challenge to energy balance in polar bears residing in some regions of the Arctic, little quantitative data exists concerning the seasonal energy expenditures of this apex marine carnivore. We used GPS satellite collars with tri-axial accelerometers and conductivity sensors to measure the location, behavior, and energy expenditure of five adult female polar bears in the southern Beaufort Sea across seasons of sea ice breakup and minimum extent. Using a Bayesian mixedeffects model, we found that energy expenditure was influenced by month, ocean depth, and habitat type (sea ice or land). Total energy expenditure from May through September ranged from 37.7 to 47.2 mJ/kg for individual bears. Bears that moved to land expended 7% more energy on average from May through September than bears that remained on the receding sea ice. In August, when bears were moving from the sea ice to land or moving north with the receding pack ice, bears that moved to land spent 7% more time swimming and expended 22% more energy. This means the immediate cost of moving to land exceeded the cost of remaining on the receding summer pack ice. These findings suggest a physiological reason why the majority of the Southern Beaufort Sea subpopulation continues to inhabit a diminishing summer ice platform. However, bears that moved to land spent 29% more time in preferred hunting habitats over the continental shelf than bears that remained on the sea ice. Bears on land also had access to subsistence-harvested bowhead whale carcasses. Hence, our findings indicate there may be a greater overall energetic benefit to move to land in this region, which suggests that the use of the diminishing summer sea ice may be functioning as an ecological trap.

Crop raiding is an increasing source of human–wildlife conflict that antagonizes humans and can lead to heightened killing of wildlife. Attraction to crops can trigger ecological traps, where animals prefer areas of their range that confer relatively low fitness. Food can be used to draw animals away from problematic areas, but an alternative considered less often is to replace high-quality food with poorer alternatives. In any case, managers often have no means of anticipating by how much such interventions should impact animal use of space. Optimal foraging theory predicts that foragers optimizing their diet should choose food items according to their relative profitability (i.e., digestible energy/ handling time), a theoretical prediction that can orient management actions. Accordingly, we developed an individual-based model (IBM) simulating movement through empirical rules under an optimal foraging framework. Our objective was to quantify the effect size of cultivating alternate crops to reduce crop raiding and the associated human-induced mortality driving an ecological trap for an energy maximizer, plains bison (Bison bison bison). Results showed that almost tripling the area of cultivation of crops of lower profitability (from 24.3% of the bison range outside the protected area in one management scenario to 70.3% in another) only led to a 25% additional decrease in the intensity of crop raiding (from a decrease of 40% in the first scenario to a decrease of 65% in the second). This suggests that localized interventions in the landscape are likely to have a stronger impact in mitigating crop raiding than broad actions ignoring spatial patterns in food distribution. However, we obtained no significant reduction in the number of simulated bison being harvested in the first scenario, and only a small reduction in the second, when the intervention was spatially broad. Our individual-based approach to animal movement informed by optimal foraging demonstrates that linking landscape configuration to mortality rates can help managers anticipate the effectiveness of manipulating food to keep animals away from problematic zones. Yet disarming ecological traps driven by human hunting appears to be a much more challenging undertaking.

Animals often disperse from one habitat to another to access mates or suitable breeding sites. The costs and benefits of such movements depend, in part, on the dispersing individuals’ phenotypes, including their sex and age. Here we investigated dispersal and road-related mortality in larvae of a bioluminescent beetle, the European common glow-worm, Lampyris noctiluca, in relation to habitat, sex and proximity of pupation. We expected these variables to be relevant to larval dispersal because adult females are wingless, whereas adult males fly when searching for glowing females. We found that dispersing glow-worm larvae were almost exclusively females and close to pupation. The larvae were often found on a road, where they were able to move at relatively high speeds, with a tendency to uphill orientation. However, each passing vehicle caused a high mortality risk, and we found large numbers of larvae run over by cars, especially close to covered, forest-like habitat patches. In contrast, adult females in the same area were most often found glowing in more open rocky and grassy habitats. These findings demonstrate an underappreciated ecological strategy, sex-biased dispersal at larval phase, motivated by different habitat needs of larvae and wingless adult females. The results are also consistent with roads being an ecological trap, facilitating dispersal and presumably females’ signal visibility but causing severe larval mortality just before the reproductive stage. Hence, in addition to the previously recognised threats of urbanisation, even low traffic volumes have a high potential to negatively affect especially females of this iconic beetle.

Although the effects of bird feeding on avian species have been extensively examined, few studies evaluate the indirect effects of bird feeding on non-target taxa. Bird seed could provide direct nourishment to several mammalian species (e.g., Lagomorpha, Rodentia, and Cetartiodactyla), potentially altering their distribution and behavior with possible unintended consequences for some avian populations, particularly those not directly benefiting from the resource. To examine how bird feeders may influence the presence and behavior of mammals, we used camera traps to quantify differences in the distribution and richness of mammal species frequenting sites with bird feeders and control sites (lacking feeders) in Ithaca, New York, USA. We recorded 15,684 images capturing 12 mammal species with gray squirrel (Sciurus carolinensis) and raccoon (Procyon lotor) detected significantly more often at feeder sites than at control sites. Detections of white-tailed deer (Odocoileus virginianus) marginally increased near feeders whereas detections of several carnivorous species were unrelated to the presence of bird feeders. We recorded larger gray squirrel and raccoon group sizes and greater mammal richness at feeder sites than at nearby control sites. We detected squirrels and raccoons less when snow covered the ground than on snow-free days. Ambient temperature was not a strong predictor of mammal detections. Camera trapping revealed strong, species-specific patterns in the timing of daily visitation to areas with feeders. Because many mammals depredate bird nests, the local increases in mammal richness and activity near bird feeders may create an ecological trap for avian species nesting in close proximity to supplemental feeding stations.

Habitat loss and forest fragmentation are currently substantially reducing the availability of natural bat roosts worldwide. However, since bat populations have been recognized as important ecosystem service providers, bat boxes have become one of the most popular measures employed to protect them. Evidence exists that in arid regions bat boxes act as ecological traps due to abrupt rises in summer temperatures. Several reported mortality events highlight the lack of appropriate guidelines in temperate areas, which might be putting bat conservation in jeopardy. We aimed to explore which bat box features might cause mortality so we compare temperatures in bat boxes, modelling the influence of the orientation and model, and quantifying the risk of extreme heat episodes. A total of 797 overheating events were recorded during a bat-box monitoring program in Catalunya (2014–2015). In 2016, we compared temperatures in up to 15 models side-by-side in the Ebro Delta Natural Park. Bat-box model and orientation clearly affected the number of overheating events. Black-coloured and south-facing boxes recorded the highest temperatures, including the most popular models, with temperatures over 40 °C. The number of overheating events was clearly dependent on the bat-box model. For example, a new model manufactured from rice chaff did not experience any overheating event in contrast with the 2F model that recorded over 50. We do not recommend the use of black boxes in south-facing sites in warm areas. In fact, observed internal temperature gradients suggest that complex boxes may help counteract the effects of overheating. We highlight the importance of taking microclimate characteristics into consideration when setting up a bat-box scheme.

To enable sustainability pathways, we need to understand how social–ecological systems (SES) respond to different governance configurations, considering their historical, institutional, political, and power conditions. We advance a robust methodological approach for the integrated analysis of those conditions in SES traps. Our advancement consists of a novel combination of the networks of action situations approach with an agency-based polycentric power typology and the concept of discursive power. We test the approach by building on previous research on the Doñana estuary–delta SES (Guadalquivir estuary), which is characterized by a rigidity trap in the context of ecosystem and water governance. Specifically, we focus on a recent hydraulic megaproject involving deep dredging in the Guadalquivir estuary, finally canceled due to its broad negative socioeconomic and environmental repercussions. According to our analysis, certain governance, institutional, and informational mechanisms currently prevent further SES degradation in Doñana. However, key governance actors are caught in a lasting coordination failure prone to mutual defection strategies owing to power dynamics and discursive-institutional inertia. Although seemingly stable due to counteractive mechanisms among actors, this situation is at continuous risk of being unbalanced by powerful actors promoting large SES interventions such as deep dredging. Such interventions bear the systemic risk of strong suppression of SES functions, and a regime shift to a lock-in trap. This overall undesirable situation might be escaped through transformative policy designs that take into account meso-level mechanisms, such as discursive power and its role in non-decision-making, pragmatic inaction, and inefficient investment and infrastructure.

The concept of \"ecological traps\" was introduced over three decades ago. An ecological trap occurs when, by various mechanisms, low-quality (yielding low fitness) habitat is more attractive than good habitat, thus coaxing individuals to settle there despite a resultant loss of fitness. Empirical work on such traps has increased dramatically in the past decade, but the converse-avoidance of high-quality habitat because it is less attractive, what we term a \"perceptual trap\"-has remained largely unexplored. Even so, depending on conditions (growth rate, strength of habitat preference, and mortality rate), such perceptual traps can be more limiting than ecological traps to population persistence. An example from field experiments with the Lesser Prairie-Chicken ( Tympanuchus pallidicinctus ) lends empirical support to the concept, and several other potential examples suggest that these traps are perhaps more prevalent than has been appreciated. Because demographic Allee effects are expected to prevent a population from growing sufficiently in a habitat that is avoided, a perceptual trap may persist even though fitness is high. Unlike an ecological trap, which may be negated by increasing habitat quality, biologists will be hard pressed to negate a perceptual trap, which will require determining which cues an animal uses to select high-quality habitat and then devising a means of enhancing those cues so that an animal is lured into the habitat.

The management of roadside habitat may be an important component of the conservation of declining pollinators, but insect mortality along roadsides can be high, creating a potential “ecological trap.” Runoff from winter applications of deicing salt can increase soil salinity along roadsides, and if this results in higher sodium levels in floral nectar, it could increase the attractiveness of roadside plants to pollinators, possibly accentuating the ecological trap effect. We compared the soil salinity in a highway median to soil collected from nearby fields and compared the Na + concentrations in nectar from common milkweed ( Asclepias syriaca ) from these two habitats. We also manipulated soil salinity in field populations of A. syriaca by adding brine solution to document changes in nectar Na + and pollinator visitation. We found that soil salinity in the median of a highway in Clarke County, VA was 2.3 times higher than the salinity of field soil, however nectar from A. syriaca in the two habitats did not differ significantly in Na + concentration. Addition of brine to field soil increased soil salinity 17-fold and significantly increased the level of Na + in A. syriaca nectar. Pollinators visited A. syriaca umbels that received the brine treatment twice as frequently as controls. Implications for insect conservation: We conclude that elevated soil salinity is capable of increasing nectar Na + and the attractiveness of A. syriaca flowers to insect pollinators, but roadside soil salinity in our study was not high enough to enhance an ecological trap effect of roadside vegetation.

Oviposition site choice affects a host of offspring phenotypes and directly impacts maternal fitness. Recent evidence suggests that oviparous reptiles often select nest sites where the landscape has been altered by anthropogenic activity, whereas natural nest sites are less often used. We leverage a long-term study of snapping turtle (Chelydra serpentina) to identify natural nest sites and anthropogenic nest sites and to compare habitat variables among nest site types. Natural and anthropogenic nest sites did not differ in average canopy closure, distance to nearest water, substrate composition, or aspect. However, anthropogenic nest sites had less ground-level vegetation and greater soil brightness, and were 3.3 °C warmer than natural nests during incubation. We used the Schoolfield model of poikilotherm development to assess differences in development rate between natural and anthropogenic nests. Because of the difference in temperature, embryos in anthropogenic nests were predicted to have undergone nearly twice as much development as embryos in natural nests during incubation. We outline why the evolution of fast embryonic development rate cannot compensate indefinitely for the low temperature incubation regimes that become increasingly prevalent at northern range margins, thereby underlining why maternal nest site choice of relatively warm anthropogenic sites may help oviparous reptiles persist in thermally constrained environments. Future research should aim to quantify both the thermal benefits of anthropogenic nest sites, as well as associated fitness costs (e.g., increased adult mortality) to elucidate whether anthropogenic disturbance of the landscape can be an ecological trap or serve a net benefit to some reptiles in northern environments.