Understanding and predicting the effects of climate change on populations requires linking the environmental conditions to demographic rates and the demographic rates to population‐level consequences, but often this complete demographic pathway is not studied. Integrated population models (IPMs) incorporate demographic data into a single analytical framework, allowing for the inclusion of environmental covariates to test hypotheses considering how the environment influences demographic rates, and consequently, to which demographic rates population growth rate is most sensitive. In birds, there is strong evidence that environmental conditions impact population growth, and that long‐distance migrant avian species with short phenological windows are at greatest risk of population decline due to changing environmental conditions. We built a Bayesian IPM with over 40 years of mark‐recapture, fecundity, and nest box occupancy data and incorporated environmental covariates hypothesized to be driving the observed changes in two populations of a fast‐lived long‐distance migrant, the European pied flycatcher. Using variance decomposition methods, we identified the demographic pathways through which environmental covariates were acting. While several environmental covariates impacted fecundity and survival, only precipitation acted via apparent juvenile and adult survival contributed significantly to variation in population growth rate. Increased precipitation during the nest initiation, incubation, and hatchling stages had negative carry‐over effects on juvenile survival during the post‐fledging and overwintering period, and increased precipitation negatively impacted adult apparent survival, likely due to the increased energetic demands of caring for eggs and hatchlings in challenging conditions and reduced availability of aerial prey. We show that linking environmental covariates to demographic rates does not sufficiently explain or predict population‐level consequences, and that decomposing variation along the complete demographic pathway is a necessary step to appropriately identify how covariates influence population dynamics.

Anthropogenic activities such as livestock grazing and deforestation are primary causes of land degradation in drylands such as the Sahel Zone of Africa, threatening the livelihoods of rural communities and biodiversity. To restore degraded habitats, measures such as farmer‐managed livestock grazing exclusion, where the native vegetation is protected and can naturally regenerate, have been implemented. Yet the benefits of such measures for biodiversity remain poorly understood, especially in regions that experience strong seasonality. Here, we used passive acoustic monitoring to study how livestock grazing exclusion affects the avifauna at the community and species level across the dry and wet seasons. Focusing on an NGO‐driven initiative that has implemented a large network of small‐scale farmer‐managed grazing exclusions in Burkina Faso, we show that species richness and occurrence probability of most bird species were higher in grazing exclusions compared to control sites. These positive effects were more pronounced during the dry season, suggesting an ecological refuge effect when resources are limited. Despite overall positive effects on birds, we found species‐ and guild‐specific responses to grazing exclusion with species positively or negatively affected. While grazing exclusions typically had negative effects on open‐habitat specialists, frugivores, insectivores, species associated with woodlands, and Afro‐Palearctic migratory species were winners. Grazing exclusions, even at small scale, show a great potential to combat desertification, reverse land degradation and halt biodiversity loss thereby being in line with the UN Decade on Ecosystem Restoration. Yet, we emphasize the need for further studies including a socioeconomic perspective to ensure durable benefits for rural communities.

Integration of agroecosystems and other working landscapes with protected lands and waters is critical to the conservation of Earth's biodiversity. Rice agroecosystems support many species by providing aquatic habitat where natural wetlands have been altered or drained. In regions with long dry seasons, rice fields and associated irrigation canals provide essential habitat for wetland‐dependent species. We quantified the spatial scale and magnitude of the effect of rice growing on the growth and survival of the giant gartersnake (Thamnophis gigas), a threatened species that persists primarily in areas of rice agriculture in the Central Valley of California, USA. We used structural causal models to identify drought condition as a key confounder to adjust for when estimating the total effect of rice growing on demographic rates. We analyzed capture‐mark‐recapture data from 19 populations of giant gartersnakes with an integrated growth–survival model and used distance‐weighted covariates to account for the decline in influence of rice with increasing distance from our study sites. We found strong support for a positive effect of rice grown within 1.9 km of a canal on giant gartersnake growth. There was also support for a positive effect of rice on giant gartersnake survival, although the spatial scale extended out to 5 km or more. Our results demonstrate how active rice growing benefits giant gartersnakes inhabiting irrigation canals and demonstrate an approach for studying landscape effects on wildlife in agroecosystems.

Farmland abandonment occurs commonly across European mountain regions, which causes triggering of habitat encroachment through shrub regeneration and natural afforestation. However, its impact on vertebrate scavenger communities and ecological processes, such as the removal of small carcasses remains poorly understood. Through an experimental paired‐plot design (grazed vs. abandoned‐rewilded habitats), we monitored 99 small carcasses over two seasons (summer and winter) in traditional livestock grazing systems in the Guadarrama Mountains (central Spain) exposed to farmland abandonment. We evaluated how the composition and structure of the scavenger community as well as scavenging dynamics of small carcasses responded to habitat encroachment and seasonal changes. Our findings indicate that habitat encroachment following farmland abandonment significantly altered the composition and structure of the scavenger community and the ecosystem service of carrion removal. Rewilded habitats supported less diverse scavenger communities, with fewer species and individuals, dominated by mammalian facultative scavengers. In grazed habitats, almost all carcasses were consumed within 5 days, while in rewilded areas carrion removal was 2.35 times slower, with longer detection, consumption, and removal times. Seasonal changes amplified these differences, with winter bringing more diverse, bird‐rich scavenger communities, but also longer carrion removal times, especially in grazed habitats. Our findings emphasize the ecological importance of small carcasses, which attract a wide range of scavengers, primarily facultative, and play a vital role in the scavenging dynamics of ecosystems. Passive rewilding has been proposed as a management strategy of no human intervention to create self‐sustaining ecosystems that support biodiversity, enhance ecosystem services, and increase resilience to environmental change. However, our study shows that farmland abandonment alters small carrion‐scavenging dynamics, reducing the effectiveness of carrion removal services and impairing bird scavengers, some of which are of conservation concern. These results highlight the need for land and wildlife managers, as well as policymakers, to consider these effects, particularly given the vast areas undergoing abandonment across Europe, and the potential implications for environmental legislation, such as the recent European Nature Restoration Law. This is crucial to ensure the maintenance of scavengers' diversity and the ecosystem service of carrion removal.

Restoring populations of native keystone species can increase landscape resilience to global change when those species create or modify ecosystems. The North American beaver (Castor canadensis) is an ecosystem engineer that increases river water storage and residence time, increasing fire resilience at the landscape level. Beaver populations in North America are significantly lower than they were historically, but over the last decade, beavers have been increasingly recognized for their ecosystem services, and reintroduction efforts throughout their historic range have become more prevalent. Here, we modeled potential beaver dam‐building capacity, associated surface water storage, and fire resilience in California's Sierra Nevada, a region at high risk of drought and wildfire. We estimate that 51% of beaver dam‐building capacity remains in this region compared to historical levels, and considerable dam capacity remains in all watersheds. Our conservative estimates suggest that beaver dams have the potential to store a total of 120 million m3 of surface water and create 2200 km2 of fire resilience in high fire risk areas. Additionally, streams where beavers have the potential to create the greatest water and fire benefits due to physical landscape and habitat characteristics are frequently found within watersheds that are at high risk for both drought and fire. Specifically, we identified five priority watersheds that have both high risk for drought and fire impacts, and have high potential to benefit from beaver conservation and restoration. Even in areas where fire and drought are less probable, the reestablishment of beavers will likely provide similar benefits. This unique approach to quantifying potential beaver benefits illustrates that wildlife can increase resilience to global change stressors and suggests that biodiversity and nature‐based climate solutions are intertwined.

Climate change and novel fire regimes increasingly challenge stewardship of forests adapted to infrequent, stand‐replacing fire. Novel fire regimes may disrupt mechanisms that sustained postfire regeneration historically, and whether fire management can promote forest resilience to future fires is uncertain. We used the individual‐based forest simulation model iLand to explore how fire exclusion zones that mimic historical burn mosaics may affect postfire tree regeneration in conifer forests of Grand Teton National Park (Wyoming, USA). We asked: (1) How do the amount and configuration of potential fire exclusion zones influence postfire tree regeneration throughout the 21st century under alternative climate scenarios? (2) How do “operational” fire exclusion zones affect postfire tree regeneration within burned patches and across the landscape by the end of the 21st century? We first conducted a factorial simulation experiment with varying amounts (10%, 30%, 50% of the landscape) and configurations (dispersed vs. clumped) of fire exclusion zones. Informed by this experiment and logistical firefighting considerations, we developed an operational scenario in which we designated mature forests surrounded by defensible fuel breaks as fire exclusion zones. Simulations were conducted under four future climate scenarios (warm‐wet, hot‐wet, warm‐dry, hot‐dry), and postfire tree regeneration densities with fire exclusion zones were compared to reference scenarios without fire exclusion zones. Regeneration of fire‐avoiding conifers (subalpine fir, Abies lasiocarpa and Engelmann spruce, Picea engelmannii) was consistently greater with fire exclusion zones, especially with ≥30% of the landscape in dispersed configuration. Fire exclusion zones had minimal effects on regeneration of fire embracers (lodgepole pine, Pinus contorta var. latifolia) and fire resisters (Douglas‐fir, Pseudotsuga menziesii var. glauca). In the operational scenario, postfire regeneration of fire‐avoiding species was greater compared to the reference scenario, especially in hot climate scenarios. Although regeneration of fire avoiders declined in operational and reference scenarios throughout the 21st century, regeneration densities were up to 10 times greater in the operational relative to the reference scenario. Our results suggest that mimicking historical burn mosaics by establishing fire exclusion zones could sustain seed sources and afford more time for subalpine conifer forests to adapt to a warmer world with more fire.

Conservation scientists have long used population viability analysis (PVA) on species count data to quantify critical decline risk, thereby informing conservation actions. These assessments typically focus on a single species rather than assemblages and assume that risk is consistent within a given life stage (e.g., across the different seasons or months of a year). However, assessing risk at overly broad temporal or spatial scales may obscure diverging population declines between predators and prey, potentially disrupting biotic interactions. In this study, we used time‐series‐based PVA for age‐0 forage fishes and their potential zooplankton prey for each month of the year in the San Francisco Estuary, over 1995–2023 (N = 175 time series). The PVA were parameterized using Multivariate Autoregressive (MAR) models that estimate long‐term population trends and variability (i.e., process error) for each population. We found widespread negative population trends across fish species (56.8%) and observed that critical decline risk is often higher in months when species peak in abundance compared to “shoulder” months. Although current decline risk is somewhat balanced between predators and their prey (mean 23.7% for fish and 21.1% for zooplankton), our time‐series models indicate trophic levels are poised to diverge over the next 10 years, with fish generally accumulating risk faster than their prey. Additionally, zooplankton showed 11.2% higher uncertainty about their near‐term critical decline risk relative to fish. These observations suggest strong, previously unreported potential for future trophic mismatches. Our results underscore the need to assess risk over finer temporal scales within and across trophic levels to better understand vulnerability, and thus inform conservation of imperiled species. Our approach is transferable and highlights the benefits of time‐series‐based PVA to understand risk of food‐web collapse in the face of climate‐induced phenological shifts.

In tropical grazer assemblies with abundant large predators, smaller herbivores have been shown to be limited by predation and food quality, while the larger species are regulated by food abundance. Much less is known about herbivore resource partitioning in temperate grazing ecosystems, where humans typically regulate large animal abundances. The Oostvaardersplassen ecosystem in the Netherlands is a unique multispecies assemblage of cattle, horses, red deer, and geese developed after the initial introduction of a few individuals in 1983. During the first 35 years, this herbivore assemblage without predation or human regulation gradually changed into an increasing dominance of the smaller herbivore species. Carrying capacity was reached around 2008, after which numbers started fluctuating depending on winter conditions. From 2018, management changed and population numbers became regulated for biodiversity and animal welfare reasons; however, population numbers still remained close to carrying capacity for several years. We used eDNA metabarcoding of dung to quantify the diet composition of cattle, horses, red deer, and geese, annually in early winter from 2018 to 2021 and calculated their niche overlap. We found strong interspecific diet overlap. Horse and cattle diets remained mostly stable with fluctuating densities of the different species, while only red deer diet showed density dependence. Interspecific niche overlap decreased with increasing red deer population size, the most abundant species. When calculated as total energy expenditure, we found that niche overlap was more linked to red deer abundance than to total herbivore energy intake. We suggest that red deer changed their diet mainly in response to their own population size, reducing their niche overlap in relation to their population increase. In this case, resource competition reduced resource availability and forced herbivores to consume different plant taxa. We conclude that in this predator‐free temperate ecosystem, inter‐ and intraspecific resource competition are key factors structuring this assemblage of different size herbivores. We find a general competitive advantage of the more diet‐flexible red deer over horses and cattle, but with also clear signs of resource partitioning.

Biodiversity can confer temporal stability to ecosystem processes through asynchrony in species' abundances and may promote asynchrony and stability of commercial fishing harvests derived from exploited species. However, the linkages between asynchrony in the population dynamics of commercially harvested species and asynchrony of associated harvests have been difficult to resolve due to ecological, social, and economic dynamics that mediate resource extraction. Here, we explored coupled human‐ecological relationships and emergent asynchrony using commercial fishing harvest data and fisheries‐independent trawl surveys in two regions (Maryland and Virginia) of Chesapeake Bay, USA, from 2002 to 2018. For each region, we sought to identify how seasonal (within‐year) asynchrony among harvested fish species contributed to (1) seasonal asynchrony in the harvests of these species and (2) within‐year stability and economic value of harvests. We found that, in Maryland, seasonal closure of striped bass (Morone saxatilis) fishing resulted in asynchrony by forcing switching to alternative stocks. In Virginia, seasonal migration of harvested species to and from the Chesapeake Bay promoted harvest compensation and therefore harvest asynchrony. However, this effect was negated by the concurrent effects of an increase in the evenness of species dynamics on harvest compensation, reflecting changes in fishing patterns, primarily following declines in the biomass of Atlantic croaker (Micropogonias undulatus). Our findings show that both social (direct management actions and behavioral responses) and emergent properties of ecological systems can influence asynchrony in dynamics of exploited populations and commercial harvests, with implications for their continued management and sustainability.