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The availability and quality of forage on the landscape constitute the foodscape within which animals make behavioral decisions to acquire food. Novel changes to the foodscape, such as human disturbance, can alter behavioral decisions that favor avoidance of perceived risk over food acquisition. Although behavioral changes and population declines often coincide with the introduction of human disturbance, the link(s) between behavior and population trajectory are difficult to elucidate. To identify a pathway by which human disturbance may affect ungulate populations, we tested the Behaviorally Mediated Forage-Loss Hypothesis, wherein behavioral avoidance is predicted to reduce use of available forage adjacent to disturbance. We used GPS collar data collected from migratory mule deer (Odocoileus hemionus) to evaluate habitat selection, movement patterns, and time-budgeting behavior in response to varying levels of forage availability and human disturbance in three different populations exposed to a gradient of energy development. Subsequently, we linked animal behavior with measured use of forage relative to human disturbance, forage availability, and quality. Mule deer avoided human disturbance at both home range and winter range scales, but showed negligible differences in vigilance rates at the site level. Use of the primary winter forage, sagebrush (Artemisia tridentata), increased as production of new annual growth increased but use decreased with proximity to disturbance. Consequently, avoidance of human disturbance prompted loss of otherwise available forage, resulting in indirect habitat loss that was 4.6-times greater than direct habitat loss from roads, well pads, and other infrastructure. The multiplicative effects of indirect habitat loss, as mediated by behavior, impaired use of the foodscape by reducing the amount of available forage for mule deer, a consequence of which may be winter ranges that support fewer animals than they did before development.

Biological invasions are a leading cause of global change, yet their long-term effects remain hard to predict. Invasive species can remain abundant for long periods of time, or exhibit population crashes that allow native communities to recover. The abundance and impact of nonnative species may also be closely tied to temporally variable habitat characteristics. We investigated the long-term effects of habitat fragmentation and invasion by the Argentine ant (Linepithema humile) by resurveying ants in 40 scrub habitat fragments in coastal southern California that were originally sampled 21 yr ago. At a landscape scale, fragment area, but not fragment age or Argentine ant mean abundance, continued to explain variation in native ant species richness; the species–area relationship between the two sample years did not differ in terms of slope or intercept. At local scales, over the last 21 yr we detected increases in the overall area invaded (+36.7%, estimated as the proportion of occupied traps) and the relative abundance of the Argentine ant (+121.95%, estimated as mean number of workers in pitfall traps). Argentine ant mean abundance also increased inward from urban edges in 2017 compared to 1996. The greater level of penetration into fragments likely reduced native ant richness by eliminating refugia for native ants in fragments that did not contain sufficient interior area. At one fragment where we sampled eight times over the last 21 yr, Argentine ant mean abundance increased over time while the diversity of native ground-foraging ants declined from 14 to 4 species. Notably, native species predicted to be particularly sensitive to the combined effect of invasion and habitat loss were not detected at any sites in our recent sampling, including the army ant genus Neivamyrmex. Conversely, two introduced ant species (Brachymyrmex patagonicus and Pheidole flavens) that were undetected in 1996 are now common and widespread at our sites. Our results indicate that behaviorally and numerically dominant invasive species can maintain high densities and suppress native diversity for extended periods.

Context Habitat fragmentation and loss are major contributing factors in the global biodiversity crisis. This is especially concerning for low-dispersing organisms in anthropized areas, where artificial elements separating suitable habitat patches impede landscape connectivity, compromising long-term population viability. Robust comparative assessments of regional population connectivity can drive evidence-based conservation measures for biological communities, but require comprehensive field surveys to provide reliable inferences. Objectives We focused on amphibians, low-dispersing taxa with declining populations worldwide, primarily due to habitat loss and fragmentation. We assessed patterns of landscape connectivity in 16 native amphibian species grouped in four communities in the most populated region in Spain (Community of Madrid). Methods We surveyed 2303 water bodies across the entire region to characterize amphibian communities and developed whole-range distribution models relating species presence data and remote sensing covariates. Then, we projected predicted global distributions in the study region with high resolution and used landscape resistance models and clustering analyses to reconstruct connectivity networks of all species and identify potential ecological corridors and barriers contributing to population fragmentation. Results We recorded 18–866 breeding sites per species, and generated models with high statistical performance. Connectivity varied spatially and across communities and species, highlighting barriers to dispersal comprising natural (mountains, rivers) and artificial features (water reservoirs, dammed rivers, urban areas), and also ecological corridors, including peri-urban green areas, river valleys, moorlands and mountain passes. Conclusions Our work presents a novel methodological framework leveraging data from local (field surveys) and global (online databases) scales across multiple species, enabling robust assessment of community-level connectivity patterns to inform conservation planning.

Outdoor recreation is increasingly recognized to impact nature and wildlife, yet few studies have examined recreation within large natural landscapes that are critical habitat to some of our most rare and potentially disturbance‐sensitive species. Over six winters (2010–2015) and four study areas (>1.1 million ha) in Idaho, Wyoming, and Montana, we studied the responses of wolverines (Gulo gulo) to backcountry winter recreation. We fit Global Positioning System (GPS) collars to 24 individual wolverines and acquired >54,000 GPS locations over 39 animal‐years during winter (January–April). Simultaneously, we monitored winter recreation, collecting ~6000 GPS tracks (~200,000 km) from backcountry recreationists. We combined the GPS tracks with trail use counts and aerial recreation surveys to map the extent and relative intensity of motorized and non‐motorized recreation. We integrated our wolverine and backcountry recreation data to (1) assess patterns of wolverine habitat selection and (2) evaluate the effect of backcountry recreation on wolverine habitat relationships. We used resource selection functions to model habitat selection of male and female wolverines within their home ranges. We first modeled habitat selection for environmental covariates to understand male and female habitat use then incorporated winter recreation covariates. We assessed the potential for indirect habitat loss from winter recreation and tested for functional responses of wolverines to differing levels and types of recreation. Motorized recreation occurred at higher intensity across a larger footprint than non‐motorized recreation in most wolverine home ranges. Wolverines avoided areas of both motorized and non‐motorized winter recreation with off‐road recreation eliciting a stronger response than road‐based recreation. Female wolverines exhibited stronger avoidance of off‐road motorized recreation and experienced higher indirect habitat loss than male wolverines. Wolverines showed negative functional responses to the level of recreation exposure within the home range, with female wolverines showing the strongest functional response to motorized winter recreation. We suggest indirect habitat loss, particularly to females, could be of concern in areas with higher recreation levels. We speculate that the potential for backcountry winter recreation to affect wolverines may increase under climate change if reduced snow pack concentrates winter recreationists and wolverines in the remaining areas of persistent snow cover.

ContextAlthough hydropower development is one of the primary drivers of habitat loss and insular fragmentation, its impacts on species identity and their functional and phylogenetic roles have often been overlooked.ObjectivesHere we use an integrative approach, considering taxonomic, functional and phylogenetic dimensions at multiple scales, to understand the processes underlying species (dis)assembly of two taxa exhibiting relatively low dispersal ability: small mammals and lizards.MethodsWe surveyed 26 islands within the Balbina Hydroelectric Reservoir, and adjacent continuous forest, in Central Amazonia. Each dimension of diversity was related to spatial and habitat variables. We also examined functional composition using community-weighted mean trait values, and community redundancy using functional uniqueness. β-diversity was partitioned into their richness (βrich) and replacement (βrepl) components.ResultsFunctional and phylogenetic α-diversities of both taxa mirrored the taxonomic dimension, all of which increased with forest area. Individual small mammal (body mass and matrix tolerance), and lizard traits (body length, heliothermic mode and habitat type) were also predicted by forest area. For both groups, functional uniqueness decreased with forest area, and all dimensions of β-diversity were predominantly partitioned in βrich.ConclusionsThe environmental filter created by forest area resulted in the low conservation value associated with small forest islands, only occupied by a small set of species comprised by generalist lizards and matrix-tolerant small mammals. On the other side, large forest sites ensured ecosystem resilience to disturbance. To maintain ecosystem integrity, creating myriad small islands over large expanses of floodwaters should be avoided in future hydropower development.

ContextHabitat loss and fragmentation can interact with other threats, including altered fire regimes, and responses to these effects can be mediated by functional traits.ObjectivesTo determine how richness and abundance of reptile trait groups respond to habitat fragmentation, patch isolation and fire.MethodsWe surveyed reptiles in 30 sites over 3 years. Sites in remnant patches in farmland were adjacent to a conservation park with either recently burnt or long-unburnt habitat. The remnant patches were stratified by distance from the reserve. Sites were spatially paired, and we experimentally burnt one of each pair in farmland. Trait groups included size, reproduction, habitat position, diet, and activity period.ResultsNone of the trait groups benefited from experimental burns, while the burns reduced abundance of viviparous, small, and above-ground species. Species richness was lower in isolated sites than in sites close to the conservation park, while generalist trait groups appeared unaffected by patch isolation. Large-sized reptiles had higher abundance in remnants. There was not more rapid colonisation of burnt sites near recently burnt conservation park. Instead, low initial abundance may have been caused by fire in combination with drought, with high rainfall during the study allowing recovery and spill-over into adjacent remnants.ConclusionsLandscape structure appears to interact with natural fires, restoration burns and longer-term climatic trends to influence the abundance and distribution of reptiles. Traits mediate responses, enabling us to formulate a set of testable mechanistic hypotheses, which illustrates a pathway to generalisation and prediction.

1. A large proportion of the world's biodiversity is reportedly threatened by habitat loss and climate change. However, there are few studies that investigate the interaction between these two threats using empirical data. 2. Here, we investigate interactions between climate change and land-use change in the future distribution of 23 dominant tree species in mainland Spain. We simulated changes up to year 2100 using a climate-dependent Stochastic Patch Occupancy Model, parameterized with colonization and extinction events recorded in 46 596 survey plots. 3. We estimated that the distribution of 17 out of 23 tree species are expanding and hence not at equilibrium with the climate. However, climate change will make the future occupancy of 15 species to be lower than expected if climate, and habitat, remained stable (baseline scenario). 4. Climate change, when combined with the loss of 20% of the habitat, was estimated to reduce species occupancies (relative to baseline projections) by an average of 23% if habitat loss was spatially clumped, and by 35% if it was scattered. If habitat loss occurred in areas already impacted by human activities, species occupancies would be reduced by 26%. Landuse changes leading to habitat gain (i.e. creation through reforestation) could slightly mitigate the effects of climate change, but a 20% increment in habitat would reduce climate changedriven losses in species occupancies by only ~ 3 %. 5. Synthesis and applications. The distributions of the most common tree species in mainland Spain are expanding, but climate change threatens to reduce this expansion by ~ 18% for 15 of the 23 studied species. Moreover, if the habitat of these species is simultaneously lost, the occupancies of all of them will be reduced further, with variation depending on the spatial pattern of the lost habitats. However, we did not detect synergies between climate change and habitat loss. The combined effect (with 20% habitat loss) was 5-13% less than what it would be if the effects were additive. Importantly, reforestation could partially offset the negative effects of climate change, but complete mitigation would require an increase in forested land of ~ 80%, and the prioritization of territories that are less impacted by human activities.

Habitat loss and fragmentation (HLF) resulting from anthropogenic disturbances is one of the greatest threats to numerous threatened taxa facing extinction risks. HLF may devastate biodiversity through various pathways such as restricting animal movement and gene flow, reducing opportunities for species to expand or shift their ranges and thus optimizing habitat use, and directly causing population decline and range contraction. Despite these well‐documented impacts, the effects of HLF on the coevolutionary processes between coexisting species are rarely examined. In this study, we constructed a cuckoo–host brood parasitism model to explore how HLF of varied degrees may affect the cuckoo–host population dynamics through stochastic and reinforcement simulations. The results, validated with empirical data, revealed that severe HLF significantly increases the cuckoo's extinction risk compared to moderate HLF. Furthermore, severe HLF narrows the range of host rejection rates that allow cuckoo populations to persist under natural conditions. These findings suggest that severe HLF, typically driven by human activities and anthropogenic land use change, may not only directly increase the extinction risk of specific species but also disrupt the coevolutionary interactions, posing more severe ecological consequences than previously anticipated. Our study explores how habitat fragmentation affects the coevolutionary dynamics between brood parasites (cuckoos) and their hosts using a stochastic, reinforcement‐based model. By incorporating both inherited traits and learned behaviors, our findings reveal how anthropogenic changes disrupt coevolutionary stability, threatening species interactions. This work provides a novel modeling framework for studying evolutionary and ecological dynamics under environmental pressures.

Ocean acidification is a threat to the net growth of tropical and deep-sea coral reefs, due to gradual changes in the balance between reef growth and loss processes. Here we go beyond identification of coral dissolution induced by ocean acidification and identify a mechanism that will lead to a loss of habitat in cold-water coral reef habitats on an ecosystem-scale. To quantify this, we present in situ and year-long laboratory evidence detailing the type of habitat shift that can be expected (in situ evidence), the mechanisms underlying this (in situ and laboratory evidence), and the timescale within which the process begins (laboratory evidence). Through application of engineering principals, we detail how increased porosity in structurally critical sections of coral framework will lead to crumbling of load-bearing material, and a potential collapse and loss of complexity of the larger habitat. Importantly, in situ evidence highlights that cold-water corals can survive beneath the aragonite saturation horizon, but in a fundamentally different way to what is currently considered a biogenic cold-water coral reef, with a loss of the majority of reef habitat. The shift from a habitat with high 3-dimensional complexity provided by both live and dead coral framework, to a habitat restricted primarily to live coral colonies with lower 3-dimensional complexity represents the main threat to future cold-water coral reefs and the biodiversity they support.

This review of metapopulation biology has a special focus on Professor Ilkka Hanski's (1953-2016) research. Hanski made seminal contributions to both empirical and theoretical metapopulation biology throughout his scientific career. Hanski's early research focused on ecological aspects of metapopulation biology, in particular how the spatial structure of a landscape influences extinction thresholds and how habitat loss and fragmentation can result in extinction debt. Hanski then used the Glanville fritillary system as a natural laboratory within which he studied genetic and evolutionary processes, such as the influence of inbreeding on extinction risk and variation in selection for dispersal traits generated by landscape variation. During the last years of his career, Hanski's work was in the forefront of the rapidly developing field of eco-evolutionary dynamics. Hanski was a pioneer in showing how molecular-level underpinnings of trait variation can explain why evolutionary change can occur rapidly in natural populations and how these changes can subsequently influence ecological dynamics.