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Ecologists have long investigated how demographic and movement parameters determine the spatial distribution and critical habitat size of a population. However, most models oversimplify movement behaviour, neglecting how landscape heterogeneity influences individual movement. We relax this assumption and introduce a reaction–advection–diffusion equation that describes population dynamics when individuals exhibit space-dependent movement bias toward preferred regions. Our model incorporates two types of these preferred regions: a high-quality habitat patch, termed 'habitat', which is included to model avoidance of degraded habitats like deforested regions; and a preferred location, such as a chemoattractant source or a watering hole, that we allow to be asymmetrically located with respect to habitat edges. In this scenario, the critical habitat size depends on both the relative position of the preferred location and the movement bias intensities. When preferred locations are near habitat edges, the critical habitat size can decrease when diffusion increases, a phenomenon called the drift paradox. Also, ecological traps arise when the habitat overcrowds due to excessive attractiveness or the preferred location is near a low-quality region. Our results highlight the importance of species-specific movement behaviour and habitat preference as drivers of population dynamics in fragmented landscapes and, therefore, in the design of protected areas. [ABSTRACT FROM AUTHOR]

Highly degraded lowland river ecosystems are of global concern to restoration practitioners. Hazardous anthropogenic structures, such as those used for water level management (i.e. pumping stations), present a mortality risk to fish and associated channelization, dredging, and removal of in‐channel and riparian vegetation during winter dramatically reduces habitat availability. Paradoxically, fish seeking habitat for predator refuge in these systems can lead to ecological traps, that is, the undesired occupation of pumping stations. Artificial habitats installed upstream could provide safe alternative refuge, but the effectiveness of this restoration technique is poorly understood. Here, we uniquely quantified habitat occupancy and preference of a ubiquitous European freshwater fish (Rutilus rutilus) between an artificial reed bed and pumping station habitat, with access to open water in a tank experiment. Generalized linear mixed models revealed that fish preferred the pumping station when the artificial habitat was absent (baseline) and when it was introduced (pre‐exclusion). Habitat management (exclusion from pumping station) was performed, during which artificial habitat occupancy was highest. When the pumping station was reintroduced (post‐exclusion), pumping station occupancy probability decreased from 87.5% (pre‐exclusion) to 3.7%, while artificial habitat occupancy probability increased from 18.4 to 87.9%. Therefore, our results demonstrate a preferential change in habitat occupancy of R. rutilus and suggest introducing artificial habitat alone may lead to restoration failures and ecological traps, stressing the need for habitat management to accompany artificial habitat restoration plans which aim to provide a safe alternative refuge for fish which occupy hazardous anthropogenic structures. [ABSTRACT FROM AUTHOR]

Aim Location Taxon Methods Results Main Conclusions Microrefugia on alpine slopes may allow species to persist in a warming climate. How plant species richness could respond to of the effectiveness of climatic buffering, defined as the difference in climate change in a microrefugium in comparison to that of an open alpine slope as mediated by competitive priority effects, is explored.Alpine habitat anywhere.Vascular plants.A simple spatially explicit model of plant species with adaptations across a climatic gradient simulates reproduction, dispersal, and mortality through climatic change. The effectiveness of microrefugia in buffering climate change and levels of competitive priority effects are included as factors that alter demographic rates in an experimental framework. Spatial patterns of microrefugia and differences in dispersal are also simulated. Differences in mean species richness were analysed.The number of species conserved, relative to an instantaneous equilibrium calculation with the same climatic change, decreases with inclusion of a period of change (transient vs. instantaneous, equilibrium change) and further with competitive priority effects. In these simulations, the number of species conserved does not simply increase with buffer effectiveness, as hypothesized, but instead is bimodal.The dip in number of species conserved in the middle range of buffer effectiveness occurs because barriers develop. These are temporal ecological traps, wherein species adapted to the middle of a climatic gradient become extinct, because their colonization of microrefugia is blocked by an extinction debt of resident species. The inertia that allows these demographic consequences is increased by competitive priorities. The highest levels of buffering and resulting inertia will not be ubiquitous but the bimodal pattern indicates that assessments of the role of microrefugia need to recognize the temporal species‐environment and species‐species interactions that will change the number of species conserved versus extinctions. [ABSTRACT FROM AUTHOR]

Fishers have intensively used drifting fish aggregating devices (DFADs) over the last three decades to facilitate their catch of tropical tunas. DFADs increase purse‐seine efficiency, potentially increasing tuna fishing mortality. They could also have impacts on tuna natural mortality and reproductive potential, and assessing the consequences of their presence at sea on tuna populations is a challenge. The use of DFADs results in a major increase in the number of floating objects, which are spatially heterogeneous at sea. To date, no converging scientific results exist regarding the effects of DFADs on the large‐scale movements and behaviour of tuna, mainly due to the difficulty of disentangling the respective roles of DFADs and environmental factors. Some biological indices show that tuna condition is lower when associated to a floating object than in a free‐swimming school. However, it is not clear whether this is the cause or the consequence of the association nor if it has long‐term effects on individuals' fitness. Further scientific progress requires (i) the collection of time series of indicators to monitor habitat change, individual behaviour, individual fitness, and population dynamics and (ii) experimental studies to identify the underlying behavioural and biological processes involved in associative behaviour. The extent of the modification of the surface habitat by the massive deployment of DFADs and the current uncertainty of the possible long‐term consequences on the individual fitness and dynamics of tuna populations argue for the need for increased awareness of this issue by Regional Fisheries Management Organisations regulating tuna fishing. [ABSTRACT FROM AUTHOR]

The Bonelli's Eagle (Aquila fasciata) is a critically endangered species in Israel, with electrocution on power lines posing a serious threat to its population. Because retrofitting of electricity pylons to prevent mortality is a slow and costly process, it is important to prioritize the pylons in the network for quick and efficient mitigation of eagle mortality. To determine which pylons need to be retrofitted, we applied a three-stage maximum entropy modeling process for identifying the risk factors posed by different environmental variables. The environmental feature with the highest correlation to electrocution is the distance to reservoirs (i.e. many electrocution events occur near water reservoirs). The reservoirs are foraging hotspots for Bonelli's Eagles in Israel's arid environment. Electricity pylons powering the reservoirs' pumping facilities tend to be the highest perches in the vicinity of many of the reservoirs, creating an ecological trap. The strong attraction of reservoirs to eagles may explain the high level of selectivity indicated by the model, suggesting that retrofitting only 3.6% of the pylons in the network would achieve 77% reduction in eagles' electrocution probability. Moreover, insulating pylons according to the model will also likely reduce electrocutions of other avian species, including Eastern Imperial Eagle (Aquila heliaca) and White-tailed Eagle (Haliaeetus albicilla). The modeling process presented here yielded 2 electrocution risk maps, one to facilitate prioritization of mitigation in Israel's existing power network and the second to support planning and designing new infrastructure. The model may help reach conservation goals for the Israeli Bonelli's Eagle and the modeling approach may also be useful in prioritizing pylon retrofitting in other arid landscapes. [ABSTRACT FROM AUTHOR]

Human villages in deserts can provide resources in an otherwise stark environment, potentially buffering against extreme environmental conditions. It is thus expected that breeding within these villages would result in higher fitness. However, choosing to raise offspring in these resource-rich environments may have unintended negative consequences. Here, we studied the breeding success of a cooperative breeding bird nesting in habitats with different levels of human disturbance—the Arabian babbler (Argya squamiceps), in the Negev desert of Israel. We recorded 42 breeding attempts from 15 groups between March and July 2022. We examined overall breeding success, brood size, and causes of nest failure. When nestlings were 6 days old, we also calculated daily change in body mass and adult provisioning rate. We found that despite higher resource abundance in villages, proximity to villages did not affect provisioning rate, and nestlings gained less mass at higher temperatures for all nests. Currently, there is no evidence that human villages are providing oases of resources for nesting babblers. Further, various conservation interventions (e.g. encouraging residents to keep cats indoors) could improve babblers' overall fitness. Ultimately, we highlight how, for some desert specialists, additional resources provided by humans may not do enough to counter potential negative effects. [ABSTRACT FROM AUTHOR]

Worldwide, artificial bat roosts (e.g., bat boxes, bark mimics, bat condos) are routinely deployed for conservation, mitigation, and community engagement. However, scant attention has been paid to developing best practices for the use of artificial roosts as conservation tools. Although bats readily occupy artificial roosts, occupancy and abundance data are misleading indicators of habitat quality. Lacking information on bat behavior, health, and fitness in artificial roosts, their conservation efficacy cannot be adequately validated. We considered the proximal and ultimate factors, such as evolutionarily reliable cues, that may prompt bats to preferentially use and show fidelity to suboptimal artificial roosts even when high‐quality alternatives are available. Possible negative health and fitness consequences for artificial roost inhabitants include exposure to unstable and extreme microclimates in poorly designed roosts, and vulnerability to larger numbers of ectoparasites in longer lasting artificial roosts that house larger bat colonies than in natural roosts. Bats using artificial roosts may have lower survival rates if predators have easy access to roosts placed in conspicuous locations. Bats may be lured into occupying low‐quality habitats if attractive artificial roosts are deployed on polluted urban and agricultural landscapes. To advance the science behind artificial bat roosts, we present testable research hypotheses and suggestions to improve the quality of artificial roosts for bats and decrease risks to occupants. Because continued loss of natural roosts may increase reliance on alternatives, such as artificial roosts, it is imperative that this conservation practice be improved. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Ecological studies investigating the effects of artificial light at night (ALAN) have primarily focused on single or a few species, and seldom on community-level dynamics. As ALAN is a potential cause of insect and biodiversity declines, community-level perspectives are essential. We empirically tested the hypothesis that moth species differentially respond to ALAN and that these responses can cause shifts in community composition. We sampled moths from prairie fragments in Colorado, USA. We tested whether local light sources, sky glow, site area and/or vegetation affected moth community diversity. We found that increased sky glow decreased moth abundance and species richness and shifted community composition. Increased sky glow shifted moth community composition when light and bait traps were combined; notably this result appears to be driven entirely by moths sampled at bait traps, which is an unbiased sampling technique. Our results show that ALAN has significant effects on moth communities and that local light sources have contrasting effects on moth community composition compared to sky glow. It is imperative that we better understand the contrasting effects of types of ALAN to comprehend the overall impacts of light pollution on biodiversity declines. This article is part of the theme issue 'Light pollution in complex ecological systems'. [ABSTRACT FROM AUTHOR]

Beak deformation, known as avian keratin disorder (AKD), can impair feeding and preening of birds, reducing their survival. This disorder is apparently caused by Poecivirus infection, although to date, the viral origin has been corroborated in only a few North American bird species. Considering that fruit‐eating birds can track spatiotemporal variations in fruit abundance and that AKD may have a viral origin, the incidence of this disease can be expected to increase with flocking by birds. Therefore, we evaluated if austral thrushes (Turdus falcklandii) were attracted to urban areas when exotic plants offered fruits and if flocking of thrushes in urban areas increased the spread of AKD in this species in a Patagonian town. We fitted GPS loggers on some individuals with normal beaks in rural areas and found that they visit the town in fall. Through point count censuses, we recorded greater abundances of thrushes with normal and deformed beaks during fall–winter in urban sites than in rural sites. However, the abundance of birds with AKD declined more (78–87%) than that of individuals with normal beaks (44–52%) during the transition from fall–winter to spring–summer. In urban zones in our study area, fruits of exotic species ripen during fall, attracting austral thrushes from rural sites. Nevertheless, such an attraction for food resources may be an ecological trap for this species, as the increase in incidence of AKD in urban areas may drastically reduce the survival of birds during the most unfavorable period of the year. [ABSTRACT FROM AUTHOR]

Trophic niche is a fundamental aspect of the ecology and natural history of animals, influencing their behavior, health, survival, and population dynamics. Although urbanization can strongly affect the trophic niche of wildlife by altering prey availability, abundance, and distribution, this effect remains understudied in tropical reptiles. Here, we assessed the influence of urbanization on the trophic niche and body condition of the West African rainbow lizard Agama picticauda in the Accra Plains of Ghana. Gastrointestinal content analysis of 98 lizards sampled from urban, suburban, and rural areas revealed 1088 prey items belonging to 14 orders and ~47 families of arthropods. Generally, the lizards consumed insects, with Hymenoptera (Formicidae) and Coleoptera (Carabidae) being the most frequently consumed prey orders. Multinomial regression modeling indicated that sex and site strongly affected the diet and body condition of the lizards, with suburban and rural lizards scoring the highest and lowest on both trophic niche breadth and body condition, respectively. We found a weak positive association between body condition and the diversity of ingested prey orders. Our data indicated that urbanization negatively influenced the trophic niche and body condition of A. picticauda. Although the differences in body condition among sites were not statistically significant, these could have important biological ramifications. The negative body condition of the urban female lizards suggests that the city could be an ecological trap, which can reduce the long-term fitness of lizards living in the urban area. Our findings can inform urban land use planning and effective conservation of urban habitats. We caution, however, that the findings of this study may not necessarily reflect the long-term trophic dynamics of rainbow lizards in the Accra Plains of Ghana and other cities. [ABSTRACT FROM AUTHOR]

Controlling small mammal pests and their damage has always been a challenge for farmers. Farmers and researchers worldwide have been experimenting with deploying nest boxes to attract barn owls to their fields to remove rodent pests. While much research has focused on the potential for nest boxes and barn owls to benefit agriculture, comparatively little work has examined the impact of the practice on owls. In this study, we used a life table analysis and estimates of barn owl reproduction measured in winegrape vineyards in Napa Valley, California coupled with published estimates of survival from long-term studies in Europe to produce a demographic model of a population of barn owls using nest boxes. We then examined how manual perturbations of survival and reproductive rates affect whether the modeled population is stable, increasing, or decreasing. Based on our empirical estimate of reproductive success and literature-sourced estimates of survival, the population appears to be growing. Across all scenarios in which we adjusted survival, there were only five that resulted in the population declining. All scenarios that resulted in population decline occurred when survival was reduced for all ages simultaneously or for adult survival independently. There were no scenarios in which lambda dropped below 1 when modifying reproductive success independent of survival. These results are important for practical pest-management reasons, as nest boxes cannot be part of a successful long-term integrated pest management (IPM) plan if they are reliant on continual immigration of adult owls from other source populations to offset mortality. A thorough examination of ecological traps should be conducted using additional information on habitat selection and reproduction in natural nest sites.

The demography of, and factors that influence these metrics, are largely unknown for most vultures in the Americas. Survivorship of Turkey Vultures (Cathartes aura) may be influenced by landscape heterogeneity and human disturbance. We quantified the effects of landscape composition (Shannon's diversity index) and configuration (contagion, edge density, and largest patch index), and human disturbance (road density) on the annual and seasonal survival probabilities of the three North American breeding populations (western, central, and eastern) of Turkey Vultures that spend the nonbreeding season in the southeastern portion of the Nearctic and the northern Neotropics during a 17-year period. We used Cox's proportional hazards models with time-varying covariates to estimate spatial and temporal changes in survival rates of adult Turkey Vultures. Road density, but not landscape composition or configuration, influenced survival rates in space and time. Overall annual survival averaged 0.87 (95% confidence interval [CI]: 0.74-0.98). Mortality risk was low in western and central populations (hazard ratio < 1) but was 3.7 times greater for vultures in the eastern population. Survival during the breeding (0.97, 95% CI: 0.96-0.98) and outbound migration (1.0, 95% CI: 1-1) seasons was significantly higher than the other seasons. Average survival tended to be higher for nonbreeding (0.81, 95% CI: 0.71-0.88) compared to return migration (0.69, 95% CI: 0.56-0.81) seasons. The risk of mortality for all vulture populations increased with road density, and this was greater during the nonbreeding and return migration seasons. The spatial variation in road density across the Americas may generate a network of ecological traps for Turkey Vultures induced to stop in areas of greater road-kill abundance. Road-killed animals acting as an attractant for vultures can increase the occurrence of vulture-vehicle collisions and potentially aggravate human-wildlife conflicts. Further analyses are needed to address survivorship and mortality factors for young birds. Our results may help the implementation of specific mitigation efforts to reduce human-vulture conflicts and vulture mortality. For instance, concentrating efforts to remove road-killed animals in areas where road density is highest can likely reduce vulture-vehicle collisions and associated mortalities of these birds. [ABSTRACT FROM AUTHOR]

Humans are increasingly recognized as important players in predator–prey dynamics by modifying landscapes. This trend has been well‐documented for large mammal communities in North American boreal forests: logging creates early seral forests that benefit ungulates such as white‐tailed deer (Odocoileus virginianus), while the combination of infrastructure development and resource extraction practices generate linear features that allow predators such as wolves (Canis lupus) to travel and forage more efficiently throughout the landscape. Disturbances from recreational activities and residential development are other major sources of human activity in boreal ecosystems that may further alter wolf–ungulate dynamics. Here, we evaluate the influence that several major types of anthropogenic landscape modifications (timber harvest, linear features, and residential infrastructure) have on where and how wolves hunt ungulate neonates in a southern boreal forest ecosystem in Minnesota, USA. We demonstrate that each major anthropogenic disturbance significantly influences wolf predation of white‐tailed deer fawns (n = 427 kill sites). In contrast with the "human shield hypothesis" that posits prey use human‐modified areas as refuge, wolves killed fawns closer to residential buildings than expected based on spatial availability. Fawns were also killed within recently‐logged areas more than expected. Concealment cover was higher at kill sites than random sites, suggesting wolves use senses other than vision, probably olfaction, to detect hidden fawns. Wolves showed strong selection for hunting along linear features, and kill sites were also closer to linear features than expected. We hypothesize that linear features facilitated wolf predation on fawns by allowing wolves to travel efficiently among high‐quality prey patches (recently logged areas, near buildings), and also increase encounter rates with olfactory cues that allow them to detect hidden fawns. These findings provide novel insight into the strategies predators use to hunt ungulate neonates and the many ways human activity alters wolf–ungulate neonate predator–prey dynamics, which have remained elusive due to the challenges of locating sites where predators kill small prey. Our research has important management and conservation implications for wolf–ungulate systems subjected to anthropogenic pressures, particularly as the range of overlap between wolves and deer expands and appears to be altering food web dynamics in boreal ecosystems. [ABSTRACT FROM AUTHOR]

When a transmission hotspot for an environmentally persistent pathogen establishes in otherwise high-quality habitat, the disease may exert a strong impact on a host population. However, fluctuating environmental conditions lead to heterogeneity in habitat quality and animal habitat preference, which may interrupt the overlap between selected and risky habitats. We evaluated spatio-temporal patterns in anthrax mortalities in a plains zebra (Equus quagga) population in Etosha National Park, Namibia, incorporating remote-sensing and host telemetry data. A higher proportion of anthrax mortalities of herbivores was detected in open habitats than in other habitat types. Resource selection functions showed that the zebra population shifted habitat selection in response to changes in rainfall and vegetation productivity. Average to high rainfall years supported larger anthrax outbreaks, with animals congregating in preferred open habitats, while a severe drought forced animals into otherwise less preferred habitats, leading to few anthrax mortalities. Thus, the timing of anthrax outbreaks was congruent with preference for open plains habitats and a corresponding increase in pathogen exposure. Given shifts in habitat preference, the overlap in high-quality habitat and high-risk habitat is intermittent, reducing the adverse consequences for the population.

For many animals, nests are essential for reproductive success. Nesting individuals need to carry out a range of potentially challenging tasks, from selecting an appropriate site and choosing suitable materials to constructing the nest and defending it against competitors, parasites and predators. Given the high fitness stakes involved, and the diverse impacts both the abiotic and social environment can have on nesting success, we might expect cognition to facilitate nesting efforts. This should be especially true under variable environmental conditions, including those changing due to anthropogenic impacts. Here, we review, across a wide range of taxa, evidence linking cognition to nesting behaviours, including selection of nesting sites and materials, nest construction, and nest defence. We also discuss how different cognitive abilities may increase an individual's nesting success. Finally, we highlight how combining experimental and comparative research can uncover the links between cognitive abilities, nesting behaviours and the evolutionary pathways that may have led to the associations between them. In so doing, the review highlights current knowledge gaps and provides suggestions for future research. This article is part of the theme issue 'The evolutionary ecology of nests: a cross-taxon approach'. [ABSTRACT FROM AUTHOR]

Anthropogenic structures extensively fragment riverine systems, reducing longitudinal connectivity, inhibiting migration and leading to severe declines in many fish populations, especially for diadromous species. This study investigated the upstream spawning migration of anadromous river lamprey (Lampetra fluviatilis) in a heavily fragmented tributary of the Humber Estuary, the location of one of the largest UK river lamprey populations. Overall, this study quantified river lamprey migration, spawning habitat distribution and historic river levels to develop a novel empirical index to understand the impact of man‐made barriers and prioritise their remediation. Passage at all weirs only occurred during episodic high river levels, often after prolonged delays with no lamprey passing below average levels for the time of year or utilising the fish pass at the first weir (T1) at the tidal limit. Barrier passage opportunities at the first four weirs were only possible for 30.3%, 38.7%, 52.1% and 6.7% of the migration period, but were lower and severely limited in 15 of the last 21 years. In addition, more lamprey (60%, n = 18) were last detected in reaches with no spawning habitat than in spawning habitat (40%, n = 12). Given the impassibility of, and lack of retreat from, T1 to other Humber tributaries, the River Trent is currently considered an ecological trap for a large proportion of lamprey that enter from the Humber Estuary. This passage should be urgently remediated, per the prioritisation index presented here, to aid river lamprey conservation, especially given their status as a designated feature of the Humber SAC. [ABSTRACT FROM AUTHOR]

Climate and land use change are two of the primary threats to global biodiversity; however, each species within a community may respond differently to these facets of global change. Although it is typically assumed that species use the habitat that is advantageous for survival and reproduction, anthropogenic changes to the environment can create ecological traps, making it critical to assess both habitat selection (e.g. where species congregate on the landscape) and the influence of selected habitats on the demographic processes that govern population dynamics.We used a long‐term (1958–2011), large‐scale, multi‐species dataset for waterfowl that spans the United States and Canada to estimate species‐specific responses to climate and land use variables in a landscape that has undergone significant environmental change across space and time. We first estimated the effects of change in climate and land use variables on habitat selection and population dynamics for nine species. We then hypothesized that species‐specific responses to environmental change would scale with life‐history traits, specifically: longevity, nesting phenology and female breeding site fidelity.We observed species‐level heterogeneity in the demographic and habitat selection responses to climate and land use change, which would complicate community‐level habitat management. Our work highlights the importance of multi‐species monitoring and community‐level analysis, even among closely related species.We detected several relationships between life‐history traits, particularly nesting phenology, and species' responses to environmental change. One species, the early‐nesting northern pintail (Anas acuta), was consistently at the extreme end of responses to land use and climate predictors and has been a species of conservation concern since their population began to decline in the 1980s. They, and the blue‐winged teal, also demonstrated a positive habitat selection response to the proportion of cropland on the landscape that simultaneously reduced abundance the following year, indicative of susceptibility to ecological traps.By distilling the diversity of species' responses to environmental change within a community, our methodological approach and findings will help improve predictions of community responses to global change and can inform multi‐species management and conservation plans in dynamic landscapes that are based on simple tenets of life‐history theory. [ABSTRACT FROM AUTHOR]

BACKGROUND: Fruit flies are important economic pests of fruits, vegetables, and nuts all over the world. In this study, a permanent ecological trap, which was created by the ovicidal effect of phytogenic hydrogen cyanide (HCN) liberated from passion fruits due to oviposition by fruit flies and can be used in the pest management, were determined. RESULTS: Observation of fruit fly eggs in Passiflora within the passion fruit cultivation region in southern China, from Aug 2019 to Oct 2020 showed that the exotic Passiflora attracted the native fruit flies to oviposit, but the eggs could not hatch. Using classical staging to categorize embryonic development and fumigation assays, we show that oviposition by fruit fly on passion fruits, release HCN from the cyanogenic mesocarp. Exposure of the eggs to HCN causes arrest of embryonic development and finally the death of eggs. CONCLUSION: Our results reveal that the life cycle of fruit fly in Passiflora is interrupted at the egg stage. Consequently, we predict that this ecological trap may be permanent. Extensive cultivation of the Passiflora vine as a dead‐end trap crop may be an effective avenue to reduce populations of fruit fly pests. © 2023 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Conversion of the North American prairies to cropland remains a prominent threat to grassland bird populations. Yet, a few species nest in these vastly modified systems. Thick‐billed longspurs historically nested in recently disturbed or sparsely vegetated patches within native mixed‐grass prairie, but observations of longspurs in spring cereal and pulse crop fields during the breeding season in northeastern Montana, USA, suggest such fields also provide cues for habitat selection. Maladaptive selection for poor‐quality habitat may contribute to ongoing declines in longspur populations, but information on thick‐billed longspur breeding ecology in crop fields is lacking. We hypothesized that crop fields may function as ecological traps; specifically, we expected that crop fields may provide cues for territory selection, but frequent human disturbance would result in reduced reproduction. To address this hypothesis, we compared measures of habitat selection (settlement patterns and trends in abundance) and productivity (nest density, nest survival, and number of young fledged) between crop fields and native grassland sites during 2020–2021. Across both years, settlement patterns were similar between site types and occupancy ranged from 0.52 ± 0.17 SE to 0.99 ± 0.01 on April 7 and 30, respectively. Early season abundance differed by year, and changes in abundance during the breeding season appeared to be associated with precipitation‐driven vegetation conditions rather than habitat type. While an index of nest density was lower in crop than native sites, the number of young fledged per successful nest (2.9 ± 0.18 SE) and nest survival (0.24 ± 0.03 SE; n = 222 nests) were similar for crop and native sites. Collectively, the data did not support our ecological trap hypothesis: longspurs did not exhibit a clear preference for crop sites and reproductive output was not significantly reduced. Our results indicate that croplands may provide alternative breeding habitat within a human‐dominated landscape. [ABSTRACT FROM AUTHOR]

By rapidly modifying key habitat components, habitat restoration is at risk of producing attractive cues for animals without providing habitats of sufficient quality. As such, individual fitness components, such as reproduction, could be reduced and restored habitats could become ecological traps. This risk notably appears by using artificial constructions in restoration projects, yet few studies have evaluated their efficacy in a robust way. We investigated this by analyzing 154 islets that were created or restored to improve the conservation status of 7 colonial Laridae species in the South of France. From 2007 to 2016, we compared occupancy dynamics and breeding parameters of these species between the restored sites and 846 unmanaged nesting sites. We also explored species' preference for different nesting site characteristics and their respective effect on breeding parameters. Restored nesting sites were 2–9 times as attractive as unmanaged sites for all species except the Black‐headed Gull (Chroicocephalus ridibundus). Colonization probability was up to 100 times higher in sites already used by other species the previous year and increased with distance to the shore until >0.2 when distance was over 250 m. Abandonment probability was 29–70% lower when breeding was successful the previous year in all species except the Sandwich Tern (Thalasseus sandvicensis). Productivity and breeding success probability were 2 times higher on managed sites. Distance from the shore was an important attractive characteristic of artificial nesting sites in all species. Other nesting site characteristics had species‐specific effects on colonization, abandonment, and breeding success. Our results indicate that managed nesting sites are successful conservation tools for colonial Laridae in the Mediterranean and do not act as ecological traps. Our study showed that testing the ecological trap hypothesis is a robust way to evaluate the success of restoration projects of breeding habitats. [ABSTRACT FROM AUTHOR]

Declining wetland areas cause many amphibian species to breed inside stormwater ponds (SWPs), which have been constructed alongside major roads to collect and retain polluted road runoff water. However, the suitability of such artificial ponds as a breeding habitat for amphibians remains unclear. Recently, a study found a very low survival rate of European green toad tadpoles (Bufotes viridis) inside SWPs, presumably because of high sediment pollution and/or the presence of a leech Helobdella stagnalis. To establish the effects of sediment pollution and leech presence on tadpole growth and survival, we exposed 480 green toad tadpoles to a number of controlled conditions inside holding tanks. We tested the following conditions: (1) 'control' (clean sediment + clean water); (2) 'leech' (clean sediment + clean water + leeches); (3) 'SWP sediment' (clean water + polluted sediment); and (4) 'SWP sediment + leech' (clean water + polluted sediment + leeches). Tadpole size and survival was monitored until metamorphosis and, individuals participated in swim tests and respirometry trials to the test potential effects of pollution on their escape capacity and metabolic rate. We found that the growth rate of tadpoles exposed to the SWP sediment (condition 3) was increased, while pollution had no effect on survival. By contrast, leeches heavily preyed upon tadpoles, leaving no survivors in conditions 2 and 4. Tadpoles swim speed and metabolic rate of toadlets did not differ between the 'control' and 'SWP sediment' group, the only conditions with surviving individuals. Our study found that leeches had the strongest effect on tadpole survival and were likely responsible for the low survival rates in SWPs observed recently. Hence, we suggest that adequate management measures are needed to limit leech penetration inside SWPs (frequent dredging/draining) to prevent these artificial structures from becoming an ecological trap for locally endangered amphibians but rather a base to help in their recovery. [ABSTRACT FROM AUTHOR]

BACKGROUND: Pesticides are one of the most important anthropogenic‐related stressors. In times of global pollinator decline, the role of integrated farming and urban gardens in supporting wild pollinators is becoming increasingly important. We circulated an online questionnaire to survey plant protection practices among Hungarian farmers and garden owners with a particular emphasis on pollinator protection. RESULTS: We found that plant growers rely heavily on pesticide use, and pesticides are used widely in otherwise pollinator‐friendly gardens. Whether pesticide use practices were driven by expert opinion and respondent gender were the best predictors of pesticide use. Although most respondents supported pollinators, pesticides are also used widely among home garden owners, which can pose a non‐evident ecological trap for pollinator populations in the gardens. CONCLUSION: Special attention should be paid to implementing measures to reduce pesticide use not only in farmland, but also in home gardens. Environmental education and financial support through agroecological schemes could efficiently promote the transition away from pesticide use. However, whereas farmers can be encouraged to reduce pesticide use mostly by expert advice, garden owners are likely to rely on more conventional information channels. The attitudes of Hungarian plant growers can provide an insight into pesticide use practices of Central and Eastern European countries, but similar surveys are needed across Europe for a complete understanding of broad‐scale processes. This work lays the foundations for similar studies that can inform and facilitate the transformation to pesticide‐free farming and gardening. © 2022 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Human-Osprey (Pandion haliaetus) conflicts are increasing as the species rebounds from the negative effects of DDT. Ospreys forage at aquaculture facilities in North America, South America, and Europe, where nonlethal and lethal control are used to reduce depredations. Under the authority of a federal depredation permit, personnel at a state-owned fish hatchery in Montana shot eight Ospreys from 2018–2020 to reduce loss of brood stock largemouth bass (Micropterus salmoides). Independent long-term data (2012–2022) of Osprey breeding ecology along the Yellowstone River, which included the hatchery, afforded a rare opportunity to examine nest occupancy and reproductive success of the local population before, during, and following lethal control. The local breeding population of Ospreys collapsed by 2021 and the breeding range contracted 48–67 km during and after shooting. Shooting at the hatchery was the greatest source of Osprey mortality on the 950-km linear study area. In 2021, an informal working group of diverse stakeholders began meeting to develop nonlethal methods to reduce Osprey depredations at the hatchery. Los conflictos entre humanos y Pandion haliaetus aumentan a medida que la especie se recupera de los efectos negativos del DDT. P. haliaetus se alimenta en instalaciones acuícolas en América del Norte, América del Sur y Europa, donde se utilizan controles no letales y letales para reducir las depredaciones. Bajo la autoridad de un permiso federal de control, el personal de una piscifactoría de propiedad estatal en Montana disparó contra ocho individuos de P. haliaetus entre 2018 y 2020 para reducir la pérdida de reproductores de Micropterus salmoides. Los datos independientes a largo plazo (2012–2022) de la ecología reproductiva de P. haliaetus a lo largo del Río Yellowstone, que incluía la piscifactoría, proporcionaron una rara oportunidad para examinar la ocupación del nido y el éxito reproductivo de la población local antes, durante y después del control letal. La población reproductora local de P. haliaetus colapsó en 2021 y el área de reproducción se contrajo de 48 a 67 km durante y después de los disparos. Los disparos en la piscifactoría fueron la mayor fuente de mortalidad de P. haliaetus en el área de estudio lineal de 950 km. En 2021, un grupo de trabajo informal de diversas partes interesadas comenzó a reunirse para desarrollar métodos no letales para reducir las depredaciones de P. haliaetus en la piscifactoría. [Traducción del equipo editorial] [ABSTRACT FROM AUTHOR]

Effective wildlife conservation requires decomposing the drivers of population dynamics for species affected by anthropogenic habitat alterations. Ungulates are often the focus of management actions to restore habitat and maintain connectivity as they are sensitive to landscape disturbances. We used Bayesian proportional hazards models to assess anthropogenic risk factors that could potentially predict landscape‐scale survivorship for pronghorn (Antilocapra americana) in the Northern Sagebrush Steppe ecosystem, where extensive habitat alterations occurred from the conversion of native sagebrush grasslands to agricultural lands. Using 170 adult female pronghorn monitored from 2003 to 2011, we tested the importance of linear features (road and fence densities) and forage productivity (maximum decadal normalized difference vegetation index [NDVI]) for spatiotemporal pronghorn mortality risk, while accounting for a seasonally varying proxy of snow depth. We found moderate support for the effects of linear features on mortality risk as coefficient estimates translated to predicted declines in survivorship of 27.1% over the observed range of road densities (0–1.4 km/km2) and 11.8% over the range of fence densities (0–6.1 km/km2) encountered by pronghorn. Our results also suggested that agricultural areas could act as ecological traps for pronghorn, based on mortality risk increasing by a factor of 14.3% with every 0.1 increase in maximum decadal NDVI in summer (range = 0.38–0.73). Like our previous findings, we found considerable support for the effects of average depth (in centimeters) of snow water equivalent (SWE; SWE depth = snow depth × snow density/water density) within pronghorn seasonal ranges, with mortality risk increasing by 45.7% with every 1 cm increase in SWE depth (range = 0–5.37 cm). We then developed the first broadscale, spatially explicit map of predicted annual pronghorn survivorship based on anthropogenic features and environmental gradients to identify areas for conservation and habitat restoration efforts. These efforts to highlight anthropogenic risk factors on the landscape will hopefully support conservation and habitat restoration for pronghorn populations at the northern periphery of their range. [ABSTRACT FROM AUTHOR]

Downstream displacement and stranding of fish are key impacts in hydropeaked rivers, adversely affecting the organisms and, subsequently, the population. While these phenomena have been extensively studied for salmonid fish, few studies have been conducted on cyprinids, particularly at heterogeneous river banks that provide nursery areas for the earliest life cycle stages. This study examines the effects of rapid flow decreases (i.e., down-ramping) on downstream displacement and stranding of common nase, Chondrostoma nasus, larvae at two river bank morphologies (a flat gravel bar and a heterogeneous river bank consisting of a sill and ditch) and daytime periods (day and night) in a mesocosm facility. For a subset of the sill and ditch experiments, stranding location was noted to quantify the trapping effect of the structure. The results show that nase larvae's downstream displacement and stranding rates were higher at the sill and ditch than at the flat gravel bar. In addition, the effects of down-ramping were more visible at night than during the day. The displacement and stranding rates were the highest for the sill and ditch structure at night. In this case, the stranding rate was four times higher in the ditch area compared to other available areas of the mesocosm. Riverbank depressions can increase the stranding risk when disconnected and dewatered from the main channel after down-ramping, constituting potential ecological traps for fish larvae. These findings highlight the need to integrate riverbank morphology and flow schemes in hydropeaking mitigation frameworks to reduce fish displacement and stranding risks. [ABSTRACT FROM AUTHOR]

Contrasting points of view on the degree and results of predation pressure in cities compared to natural/rural landscapes are considered. One of these points of view states that it is decreased due to the absence of some key native predator species and the impoverishment in species composition of predator assemblages, and the other states that it is increased due to the high abundance of synanthropic and domestic predators. The absence of some forms of intense human persecution in modern cities, such as hunting, also fits well with the first view, although this cannot be considered a main attractive factor for all urban species, since most of them are not persecuted outside cities as well. It has been shown that the data in the world literature on reproductive losses caused by predation (these are mainly data on nest predation) are very contradictory, and there are many studies in favor of each of the hypotheses. Different groups of prey, such as hole- and open-nesting species, are vulnerable to varying degrees to one or another nest predator, so losses can be reduced for some species and increased for others in the same city. In one species at different periods of time or in different prey species, processes corresponding to both points of view can occur at the same time. It is not yet possible to judge the correctness of opinions concerning predation pressure on adults due to an acute lack of data. The indirect trait-mediated effects of the presence of predators in urban versus non-urban environments also awaits study. [ABSTRACT FROM AUTHOR]

Biological invasions cause species extinction but can also provide benefits. Wetlands, such as salt marshes, include little-known but important ecosystems that are sometimes severely invaded by exotic plants. Salt marshes in eastern South America are increasingly impacted by invasions of the African grass Urochloa arrecta. This study investigated the appearance of a population of the mangrove rail Rallus longirostris in areas dominated by U. arrecta and its disappearance with the eradication of this plant. We monitored four areas (54.47 ha) in the Guaratuba Bay estuary in southern Brazil, from 2006 to 2022, two of which contained four patches of U. arrecta as the dominant species. In 2012, we started to eradicate U. arrecta with mechanical management, and in 2020, it was eradicated locally. We recorded R. longirostris for the first time within a patch of U. arrecta in 2007. In subsequent years we saw the species in two other patches of the exotic plant. Rallus longirostris was no longer observed once U. arrecta was eradicated. Differences in patch occupancy between invaded and uninvaded habitats observed for R. longirostris and Pardirallus nigricans, and the disappearance of R. longirostris following the exotic plant management suggest competitive advantage and/or differential habitat preference and population density as hypotheses to explain observed patterns. The invasion of U. arrecta can increase the local populations of R. longirostris. Since this bird is not endangered, we encourage the management of U. arrecta because of its impact on salt marshes, including an endemic endangered bird. [ABSTRACT FROM AUTHOR]

Conventional agriculture occupies a substantial portion of Earth's terrestrial surface and adversely affects biodiversity through pesticide spread, mechanisation, and loss of spatial and temporal heterogeneity of farmed landscapes. Consequently, conventional agriculture has become a primary target of many restoration projects operating at various scales, from habitat to landscape. While these restoration efforts aim to increase farmland biodiversity and promote the delivery of associated ecosystem services, unintended consequences may arise when important threats are not mitigated. For instance, animals may be led to make maladaptive choices, and lured to attractive sites with poor habitat quality (ecological traps), resulting in adverse effects on individual fitness and demography. We focus our review on European farmland as a case study because of its extensive presence on the continent and the particularly articulated legal framework regulating agriculture and biodiversity within the European Union. Europe's policy framework is dual-faced: one promotes farmland development regardless of management practices, while the other advocates for biodiversity protection measures that sometimes lack strong supporting evidence or overlook critical management aspects. Insectivorous bats contribute significantly to ecosystem service delivery through insectivory in agricultural landscapes, consuming large numbers of pest arthropods. However, when restoring habitats for bats in conventional farmland, potential unintended outcomes must be considered, particularly if restoration actions are not accompanied by mitigation of key threats. These threats include the persistent and widespread use of pesticides, road networks, the siting of wind turbines in farmed landscapes, and opportunistic predators, especially domestic cats. We argue that installing bat boxes and enhancing habitat and landscape features, such as increasing connectivity and diversity, potentially trap bats in attractive yet unsuitable environments if such threats are not mitigated. While environmental restoration in farmland is highly valued for supporting bat populations, it is crucial to avoid neglecting factors that could have the opposite effect, turning 'improved' farmland into a sink. Research is urgently needed to understand such potential unintended effects and inform farmland management and policymakers. [Display omitted] • Intensive agriculture harms bats via pesticides, infrastructures, and predators. • Bats make maladaptive habitat choices when restoration actions ignore such threats. • Enhancing conventional farmland for bats may turn it into a demographic sink. • Improvements should only be applied where threats are effectively mitigated. [ABSTRACT FROM AUTHOR]

Abstract Effective wildlife conservation requires decomposing the drivers of population dynamics for species affected by anthropogenic habitat alterations. Ungulates are often the focus of management actions to restore habitat and maintain connectivity as they are sensitive to landscape disturbances. We used Bayesian proportional hazards models to assess anthropogenic risk factors that could potentially predict landscape‐scale survivorship for pronghorn (Antilocapra americana) in the Northern Sagebrush Steppe ecosystem, where extensive habitat alterations occurred from the conversion of native sagebrush grasslands to agricultural lands. Using 170 adult female pronghorn monitored from 2003 to 2011, we tested the importance of linear features (road and fence densities) and forage productivity (maximum decadal normalized difference vegetation index [NDVI]) for spatiotemporal pronghorn mortality risk, while accounting for a seasonally varying proxy of snow depth. We found moderate support for the effects of linear features on mortality risk as coefficient estimates translated to predicted declines in survivorship of 27.1% over the observed range of road densities (0–1.4 km/km2) and 11.8% over the range of fence densities (0–6.1 km/km2) encountered by pronghorn. Our results also suggested that agricultural areas could act as ecological traps for pronghorn, based on mortality risk increasing by a factor of 14.3% with every 0.1 increase in maximum decadal NDVI in summer (range = 0.38–0.73). Like our previous findings, we found considerable support for the effects of average depth (in centimeters) of snow water equivalent (SWE; SWE depth = snow depth × snow density/water density) within pronghorn seasonal ranges, with mortality risk increasing by 45.7% with every 1 cm increase in SWE depth (range = 0–5.37 cm). We then developed the first broadscale, spatially explicit map of predicted annual pronghorn survivorship based on anthropogenic features and environmental gradients to identify areas for conservation and habitat restoration efforts. These efforts to highlight anthropogenic risk factors on the landscape will hopefully support conservation and habitat restoration for pronghorn populations at the northern periphery of their range.

New evidence points to substantial impacts of exposure to pesticide residues in soil for a range of bee taxa that have close regular contact with this substrate. Among others, the risk of exposure is high for bumblebee (Bombus spp.) queens hibernating in agricultural soils. An important question is whether bumblebee queens can detect and avoid pesticide-contaminated soils, or whether they might be attracted to such agrochemical residues. To address this question, we performed a multiple-choice preference experiment in which newly emerged bumblebee (Bombus impatiens) queens were given access to arrays of 36 crates of soil treated with different pesticides in large mesh-covered enclosures. Five of the most commonly encountered pesticides in agricultural soils (boscalid, chlorantraniliprole, clothianidin, cyantraniliprole, difenoconazole) were selected for testing at two contamination levels (lower or higher), based on field-realistic exposure estimates. Bumblebee queens consistently avoided hibernating in pesticide-free soil at both contamination levels, while showing no avoidance for any pesticide-treated soil types. At the lower contamination level, queens selected the pesticide-free soil 1.3 to 2.4-fold less frequently on average than any of the spiked soils, while none of the queens from the higher contamination group selected pesticide-free soil. This apparent preference for pesticide-contaminated soils increases the likelihood of exposure to and potential hazard from pesticide residues in soil for bumblebee queens during hibernation, a critical and highly vulnerable period of their annual life cycle., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier B.V. All rights reserved.)

Abstract Animals are expected to select a breeding habitat using cues that should reflect, directly or not, the fitness outcome of the different habitat options. However, human‐induced environmental changes can alter the relationships between habitat characteristics and their fitness consequences, leading to maladaptive habitat choices. The most severe case of such nonideal habitat selection is the ecological trap, which occurs when individuals prefer to settle in poor‐quality habitats while better ones are available. Here, we studied the adaptiveness of nest box selection in a tree swallow (Tachycineta bicolor) population breeding over a 10‐year period in a network of 400 nest boxes distributed along a gradient of agricultural intensification in southern Québec, Canada. We first examined the effects of multiple environmental and social habitat characteristics on nest box preference to identify potential settlement cues. We then assessed the links between those cues and habitat quality as defined by the reproductive performance of individuals that settled early or late in nest boxes. We found that tree swallows preferred nesting in open habitats with high cover of perennial forage crops, high spring insect biomass, and high density of house sparrows (Passer domesticus), their main competitors for nest sites. They also preferred nesting where the density of breeders and their mean number of fledglings during the previous year were high. However, we detected mismatches between preference and habitat quality for several environmental variables. The density of competitors and conspecific social information showed severe mismatches, as their relationships to preference and breeding success went in opposite direction under certain circumstances. Spring food availability and agricultural landscape context, while related to preferences, were not related to breeding success. Overall, our study emphasizes the complexity of habitat selection behavior and provides evidence that multiple mechanisms may potentially lead to an ecological trap in farmlands.

Numerous wildlife species within semi-arid shrubland ecosystems across western North America are experiencing substantial habitat loss and fragmentation. These changes in habitat are often attributed to a diverse suite of factors including prolonged and increasingly severe droughts, conifer expansion, anthropogenic development, domestic and feral livestock grazing, and invasion of exotic annual grasses, which promotes increased wildfire frequency and severity. Greater sage-grouse (Centrocercus urophasianus; hereafter, sage-grouse) are considered an indicator of sagebrush ecosystem health and have experienced widespread population decline associated with habitat loss and degradation, as well as changes in predator communities. Our objectives were to model and map sage-grouse habitat selection and survival during the important brood-rearing life stage in relation to landscape-scale environmental predictors. Furthermore, we sought to understand impacts of wildfire and annual grass invasion on brood habitat, as these accelerated disturbance regimes are a primary cause of habitat loss within the Great Basin region of the USA. We used a hierarchical Bayesian modeling framework to estimate resource selection functions and survival for early and late brood-rearing stages of sage-grouse in relation to a broad suite of habitat characteristics evaluated at multiple spatial scales within the Great Basin from 2009 to 2019. Sage-grouse selected for greater perennial grass cover, higher relative elevations, and areas closer to springs and wet meadows during both early and late brood-rearing. Terrain characteristics, including heat load and aspect, were important in survival models, as was variation in shrub height. We also found strong evidence for higher survival for both early and late broods within previously burned areas, but survival within burned areas decreased as annual grass cover (i.e. cheatgrass, Bromus tectorum) increased. This interaction effect demonstrates how invasion of annual grasses into burned areas, which has become prevalent in Great Basin sagebrush ecosystems, can lead to maladaptive habitat selection by brood-rearing greater sage-grouse. Understanding these complex relationships aids wildlife conservation and habitat management as wildfire and annual grass cycles continue to accelerate across western ecosystems.

The invasion of a novel host species can create a mismatch in host choice and offspring survival (performance) when native parasitoids attempt to exploit the invasive host without being able to circumvent its resistance mechanisms. Invasive hosts can therefore act as evolutionary trap reducing parasitoids' fitness and this may eventually lead to their extinction. Yet, escape from the trap can occur when parasitoids evolve behavioral avoidance or a physiological strategy compatible with the trap host, resulting in either host‐range expansion or a complete host‐shift. We developed an individual based model to investigate which conditions promote parasitoids to evolve behavioral preference that matches their performance, including host‐trap avoidance, and which conditions lead to adaptations to the unsuitable hosts. The model was inspired by solitary endo‐parasitoids attacking larval host stages. One important aspect of these conditions was reduced host survival during incompatible interaction, where a failed parasitization attempt by a parasitoid resulted not only in death of her offspring but also in host killing. This non‐reproductive host mortality had a strong influence on the likelihood of establishment of novel host–parasitoid relationship, in some cases constraining adaptation to the trap host species. Moreover, our model revealed that host‐search efficiency and genetic variation in host‐preference play a key role in the likelihood that parasitoids will include the suboptimal host in their host range, or will evolve behavioral avoidance resulting in specialization and host‐range conservation, respectively. Hence, invasive species might change the evolutionary trajectory of native parasitoid species, which is important for predicting biocontrol ability of native parasitoids towards novel hosts. [ABSTRACT FROM AUTHOR]

Since its introduction to North America from Asia in 2014, the spotted lanternfly has emerged as a pest in rural and suburban settings. In downtown Philadelphia we found adults of the spotted lanternfly concentrated on pavement at the bases of skyscrapers and high-rises. Most of these insects were sluggish or dead. Adults of the spotted lanternfly concentrated also on the 27th story of a façade of a high-rise, and on the roof of another high-rise. Skyscrapers and high-rises in this city behaved as ecological traps. The possibility that the spotted lanternfly will evolve resistance to such traps is doubtful. [ABSTRACT FROM AUTHOR]

Ecologists and evolutionary biologists have revealed that adaptive microevolution (i.e., allele frequency changes through time) and behavioral changes occur rapidly enough to affect contemporary ecological dynamics, and we can consider rapid adaptation for better conservation and management of wild populations. However, previous studies tended to focus on adaptation that increases population densities (e.g., evolutionary rescue), and did not pay attention to adaptation that decreases population densities (e.g., evolutionary suicide). Here, we demonstrate that controlling trait adaptation may be potentially important for decreasing population densities. One possibility is introducing "selfish" genotypes to populations. If the genotypes increase their reproductive success at the expense of population growth (e.g., cheaters in subsocial ants or coercive males in damselflies), we can decrease population densities (intraspecific adaptation load). The other possible option is diverting trait values of animals from the value that maximizes population growth (ecological trap). For example, we may be able to change behavior of a deer population by hunting so that they will not approach the best habitat with ample resources (landscape of fear). Then, we can consider the optimal allocation of our effort to directly decrease their population densities and control their trait values. However, we should carefully conduct controlling trait adaptation because it may result in unintended outcomes through modified genetic compositions and behaviors, such as increasing genetic variation of the focal population that enhances adaptation to changing environments by introducing selfish genotypes or a transient increase of population densities by modified behaviors. [ABSTRACT FROM AUTHOR]

Abstract The invasion of a novel host species can create a mismatch in host choice and offspring survival (performance) when native parasitoids attempt to exploit the invasive host without being able to circumvent its resistance mechanisms. Invasive hosts can therefore act as evolutionary trap reducing parasitoids' fitness and this may eventually lead to their extinction. Yet, escape from the trap can occur when parasitoids evolve behavioral avoidance or a physiological strategy compatible with the trap host, resulting in either host‐range expansion or a complete host‐shift. We developed an individual based model to investigate which conditions promote parasitoids to evolve behavioral preference that matches their performance, including host‐trap avoidance, and which conditions lead to adaptations to the unsuitable hosts. The model was inspired by solitary endo‐parasitoids attacking larval host stages. One important aspect of these conditions was reduced host survival during incompatible interaction, where a failed parasitization attempt by a parasitoid resulted not only in death of her offspring but also in host killing. This non‐reproductive host mortality had a strong influence on the likelihood of establishment of novel host–parasitoid relationship, in some cases constraining adaptation to the trap host species. Moreover, our model revealed that host‐search efficiency and genetic variation in host‐preference play a key role in the likelihood that parasitoids will include the suboptimal host in their host range, or will evolve behavioral avoidance resulting in specialization and host‐range conservation, respectively. Hence, invasive species might change the evolutionary trajectory of native parasitoid species, which is important for predicting biocontrol ability of native parasitoids towards novel hosts.

Abstract Bat fatalities at wind energy facilities in North America are predominantly comprised of migratory, tree‐dependent species, but it is unclear why these bats are at higher risk. Factors influencing bat susceptibility to wind turbines might be revealed by temporal patterns in their behaviors around these dynamic landscape structures. In northern temperate zones, fatalities occur mostly from July through October, but whether this reflects seasonally variable behaviors, passage of migrants, or some combination of factors remains unknown. In this study, we examined video imagery spanning one year in the state of Colorado in the United States, to characterize patterns of seasonal and nightly variability in bat behavior at a wind turbine. We detected bats on 177 of 306 nights representing approximately 3,800 hr of video and > 2,000 discrete bat events. We observed bats approaching the turbine throughout the night across all months during which bats were observed. Two distinct seasonal peaks of bat activity occurred in July and September, representing 30% and 42% increases in discrete bat events from the preceding months June and August, respectively. Bats exhibited behaviors around the turbine that increased in both diversity and duration in July and September. The peaks in bat events were reflected in chasing and turbine approach behaviors. Many of the bat events involved multiple approaches to the turbine, including when bats were displaced through the air by moving blades. The seasonal and nightly patterns we observed were consistent with the possibility that wind turbines invoke investigative behaviors in bats in late summer and autumn coincident with migration and that bats may return and fly close to wind turbines even after experiencing potentially disruptive stimuli like moving blades. Our results point to the need for a deeper understanding of the seasonality, drivers, and characteristics of bat movement across spatial scales.

Declining wetland areas cause many amphibian species to breed inside stormwater ponds (SWPs), which have been constructed alongside major roads to collect and retain polluted road runoff water. However, the suitability of such artificial ponds as a breeding habitat for amphibians remains unclear. Recently, a study found a very low survival rate of European green toad tadpoles (Bufotes viridis) inside SWPs, presumably because of high sediment pollution and/or the presence of a leech Helobdella stagnalis. To establish the effects of sediment pollution and leech presence on tadpole growth and survival, we exposed 480 green toad tadpoles to a number of controlled conditions inside holding tanks. We tested the following conditions: (1) ‘control’ (clean sediment + clean water); (2) ‘leech’ (clean sediment + clean water + leeches); (3) ‘SWP sediment’ (clean water + polluted sediment); and (4) ‘SWP sediment + leech’ (clean water + polluted sediment + leeches). Tadpole size and survival was monitored until metamorphosis and, individuals participated in swim tests and respirometry trials to the test potential effects of pollution on their escape capacity and metabolic rate. We found that the growth rate of tadpoles exposed to the SWP sediment (condition 3) was increased, while pollution had no effect on survival. By contrast, leeches heavily preyed upon tadpoles, leaving no survivors in conditions 2 and 4. Tadpoles swim speed and metabolic rate of toadlets did not differ between the ‘control’ and ‘SWP sediment’ group, the only conditions with surviving individuals. Our study found that leeches had the strongest effect on tadpole survival and were likely responsible for the low survival rates in SWPs observed recently. Hence, we suggest that adequate management measures are needed to limit leech penetration inside SWPs (frequent dredging/draining) to prevent these artificial structures from becoming an ecological trap for locally endangered amphibians but rather a base to help in their recovery.

Animals' fear of people is widespread across taxa and can mitigate the risk of human‐induced mortality, facilitating coexistence in human‐dominated landscapes. However, humans can be unpredictable predators and anthropogenic cues that animals perceive may not be reliable indicators of the risk of being killed. In these cases, animal fear responses may be ineffective and may even exacerbate the risk of anthropogenic mortality. Here, we explore these questions using a 10‐year dataset of movement and mortality events for the puma Puma concolor population in the fragmented Santa Cruz Mountains of California, for whom the leading cause of death was retaliatory killings by people following livestock loss. We modeled retaliatory killing risk and puma habitat selection relative to residential housing density to evaluate whether puma avoidance of human cues reflected their risk of being killed. We documented a mismatch between human cues, fear responses and actual risk. Rather than scaling directly with housing density, retaliatory killings occurred at intermediate levels of human development and at night. Pumas avoided these areas during the day but selected for these high‐risk areas at night, resulting in a mismatch between cue and risk impacting 17% of the study area. These results are unlikely to be driven by puma hunting behavior: livestock constitute a very small proportion of puma diets, and we found no evidence for the alternative hypothesis that state‐dependent foraging drove depredation of livestock and subsequent retaliatory killings. Our findings indicate that puma responses to human cues are not sufficient to enable human–carnivore coexistence in this area and suggest that reducing risk from humans in places with few perceptible human cues would facilitate carnivore conservation in human‐dominated landscapes. Furthermore, a mismatch between human cues and responses by carnivores can lead to selection rather than avoidance of risky areas, which could result in an ecological trap. [ABSTRACT FROM AUTHOR]

Unmasking the ecological processes responsible for the dynamics of a population is a necessary step toward understanding its threats and viability. We examined a fitness proxy (reproductive success) of an endangered raptor in relation to its ecological niche and spatial distribution to provide insights into the dynamics and potential threats to the population. We first studied how biotic and abiotic conditions drive both the spatial distribution of Bonelli's eagle (Aquila fasciata) and its long‐term reproductive success in a large area of northwestern Spain. We focused on the relationship between these two characteristics of the population. Our results showed that biotic factors (occurrence of competitors such as the golden eagle or prey availability) were more associated with the spatial distribution of the species than with its reproductive success. In contrast, abiotic factors describing climate were linked to reproductive success. Most interestingly, we found a mismatch between spatial suitability and reproductive success because reproduction was compromised in the areas that were more suitable for the occurrence of the species. The results suggest that productivity (less than one chick per year), measured as long‐term reproductive success, may compromise the population viability and suggest the presence of an underlying mechanism in the population. Our results highlight the benefits of simultaneously considering both large‐scale spatial distribution patterns and measures of fitness, which often require larger investments of time, for endangered species conservation programs. [ABSTRACT FROM AUTHOR]

Wildlife‐vehicle collisions (WVCs) represent a serious source of mortality for many species, threatening local populations' persistence while also carrying high economic and human safety costs. Animals may adapt their behaviour to road‐associated threats, but roadside resources can also attract individuals to dangerous roadside habitats, ultimately acting as an ecological trap. Yet, the extent to which individuals modify their behaviour and space use to roads is largely unknown for most taxonomic groups. Using fine‐scale movement data from 38 giant anteaters Myrmecophaga tridactyla tracked in the Brazilian Cerrado, we aimed to identify facets of movement behaviour that might exhibit plasticity to roads and traffic volume. Specifically, the analysis of daily and instantaneous movement speeds, home‐range characteristics and crossing rates/times allowed us to test for an effect of road proximity, traffic volume and natural linear features on movement behaviour. We found no effect of road proximity or traffic volume on space use or movement behaviour. While individuals tended to reduce their movement speed when approaching roads and crossed roads ~3 times less than would have been expected by random chance, none of the three highways we monitored were impervious. The majority of tracked anteaters living near roads (<2 km) crossed them, with higher crossing rates for males than females. Habitat near roads may function as an ecological trap where healthy individuals occupy the territories nearby or bisected by roads but eventually are road‐killed given their regular crossings, leaving the territory vacant for subsequent occupation. Crucially, we found no evidence that anteaters actively searched for passage structures to cross the roads. This suggests that crossing structures alone are unlikely to mitigate WVC‐induced mortality in giant anteaters. Our research reinforces the need to implement fencing, leading to existing passages, and minimizing the amount of night‐time driving to reduce the number of WVCs. [ABSTRACT FROM AUTHOR]

American eels (Anguilla rostrata) are vulnerable to turbine‐induced mortality during outmigration along regulated rivers. Turbine‐induced mortality is cumulative when multiple facilities are encountered along the route. This level of mortality may be unsustainable such that facilitating upstream movement ostensibly for recovery purposes, may in fact be detrimental to the population or an ecological trap. The objectives of this study were to estimate a theoretical threshold for facilitating upstream movement passed hydroelectric facilities and estimating cumulative turbine mortality within waterbodies across American eel's historical range within Ontario, Canada. A stage‐structured model was used to estimate mortality thresholds parameterized by published life stage survival probabilities using a maternal effect and altering silver eel survival to mimic turbine mortality. The threshold was exceeded when population growth (λ) declined below 1.0. Site mortality was estimated based on the generating station characteristics including turbine type, size, proportion of flow through turbines, and sluice gate height. Cumulative mortality within a waterbody was projected using a Bayesian network (i.e., conditional probability) and the calculated site‐specific mortality. The survival required for a stable population using the stage‐structured model was 0.75; (0.65–0.85) therefore, annual mortality greater than 0.25 (0.15–0.35) would result in population decline (λ < 1). The effects of turbine mortality increased with additional hydroelectric facilities encountered along the route. Across Ontario, there was no eel habitat deemed to be safe in terms of levels of cumulative turbine mortality during outmigration. Moreover, 89.1% of eel habitat was considered to be within the cautionary range of turbine mortality, whereas 10.9% of eel habitat was considered to be above the threshold for sustainable passage during outmigration. Lake Ontario accounted for 98.2% of the area within the cautionary range, whereas most of the tributaries and watersheds associated with the Ottawa River and Lake Ontario were above the threshold. [ABSTRACT FROM AUTHOR]

Ecological light pollution is now recognized as a significant source of ecosystem alteration. We documented that holiday lights are a seasonal source of light pollution that constitute an ecological trap for eastern fox squirrels (Sciurus niger). Texas A&M University-Kingsville (TAMUK) wildlife students surveyed a 2-km walking transect 5 times per month each month for the relative abundance and diel behavior of eastern fox squirrels and feral cats (Felis catus) on the TAMUK campus during 2018-2019. Eastern fox squirrels exhibited diurnal behaviors throughout the year but extended their foraging behavior nearly 4 hours after sunset with the addition of holiday lights. Feral cats and owls (Strigiformes) exhibited diurnal and nocturnal behaviors but conducted the majority of their hunting during crepuscular hours. We documented that monthly squirrel mortality increased 7-fold with the addition of holiday lights, possibly due to the extension of foraging time by squirrels. Although seasonal lighting is intended to be festive for humans, it can have negative consequences for eastern fox squirrels. Educating the public concerning the issue of light pollution on wildlife species is needed because the majority of the public appears unaware that bright lights can negatively alter wildlife behaviors. Reducing light intensity by either using less outdoor lights or perhaps using colored lights rather than clear white bulbs may lessen the negative effect on foraging behavior of squirrels. [ABSTRACT FROM AUTHOR]

Abstract Predators are a particularly critical component of habitat quality, as they affect survival, morphology, behavior, population size, and community structure through both consumptive and non‐consumptive effects. Non‐consumptive effects can often exceed consumptive effects, but their relative importance is undetermined in many systems. Our objective was to determine the consumptive and non‐consumptive effects of a predaceous aquatic insect, Notonecta irrorata, on colonizing aquatic beetles. We tested how N. irrorata affected survival and habitat selection of colonizing aquatic beetles, how beetle traits contributed to their vulnerability to predation by N. irrorata, and how combined consumptive and non‐consumptive effects affected populations and community structure. Predation vulnerabilities ranged from 0% to 95% mortality, with size, swimming, and exoskeleton traits generating species‐specific vulnerabilities. Habitat selection ranged from predator avoidance to preferentially colonizing predator patches. Attraction of Dytiscidae to N. irrorata may be a natural ecological trap given similar cues produced by these taxa. Hence, species‐specific habitat selection by prey can be either predator‐avoidance responses that reduce consumptive effects, or responses that magnify predator effects. Notonecta irrorata had both strong consumptive and non‐consumptive effects on populations and communities, while combined effects predicted even more distinct communities and populations across patches with or without predators. Our results illustrate that an aquatic invertebrate predator can have functionally unique consumptive effects on prey, attracting and repelling prey, while prey have functionally unique responses to predators. Determining species‐specific consumptive and non‐consumptive effects is important to understand patterns of species diversity across landscapes.

Climate change can not only increase the exposure of organisms to higher temperatures but can also drive phenological shifts that alter their susceptibility to conditions at the onset of breeding cycles. Organisms rely on climatic cues to time annual life cycle events, but the extent to which climate change has altered cue reliability remains unclear. Here, we examined the risk of a "climate trap"—a climatically driven desynchronization of the cues that determine life cycle events and fitness later in the season in a temperate reptile, the European adder (Vipera berus). During the winter, adders hibernate underground, buffered against subzero temperatures, and re‐emerge in the spring to reproduce. We derived annual spring‐emergence trends between 1983 and 2017 from historical observations in Cornwall, UK, and related these trends to the microclimatic conditions that adders experienced. Using a mechanistic microclimate model, we computed below‐ and near‐ground temperatures to derive accumulated degree‐hour and absolute temperature thresholds that predicted annual spring‐emergence timing. Trends in annual‐emergence timing and subsequent exposure to ground frost were then quantified. We found that adders have advanced their phenology toward earlier emergence. Earlier emergence was associated with increased exposure to ground frost and, contradicting the expected effects of macroclimate warming, increased post‐emergence exposure to ground frost at some locations. The susceptibility of adders to this "climate trap" was related to the rate at which frost risk diminishes relative to advancement in phenology, which depends on the seasonality of climate. We emphasize the need to consider exposure to changing microclimatic conditions when forecasting biological impacts of climate change. [ABSTRACT FROM AUTHOR]