Ecological Applications[JOURNAL]
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200 papers
Plant-derived environmental DNA reveals fine-scaled community differentiation in grassland arthropods.
Mahla L, Becker J, Groß L … +3 more , Tiltmann AS, Kennedy S, Krehenwinkel H
Ecol Appl · 2025 Dec · PMID 41419325 · Full text
The loss of plant diversity in grasslands is implicated as one of the main causes of arthropod decline. The loss of a single plant species can have a cascading effect on specialized arthropod species. It is thus critical...
The loss of plant diversity in grasslands is implicated as one of the main causes of arthropod decline. The loss of a single plant species can have a cascading effect on specialized arthropod species. It is thus critical to expand our understanding of plant-arthropod interactions. Detecting plant-arthropod interactions, however, has been difficult, as it requires the observation of individual plant visits. A possible solution to this problem is offered by environmental DNA (eDNA) analysis. Here, we test the utility of eDNA to detect fine-scaled community differentiation in grassland arthropods in Germany. Based on eDNA from 13 plant species, we explore community differentiation between plant species, and between flower and green parts of individual plants. We show that eDNA successfully recovers extremely fine-scaled community differentiation. Plant species, as well as plant compartment, emerge as major drivers of arthropod community composition in grasslands, with the differentiation being particularly pronounced in herbivorous arthropods. Terrestrial eDNA on plants thus appears to be deposited in a very localized fashion, making this tool ideally suited to detect very fine-scaled community differentiation. Considering the high specificity we observe in our analysis, our results highlight the necessity of integrating vegetation surveys into future monitoring of arthropod communities.
A framework to analyze biodiversity capacity at landscape level and identify areas of high ecological importance.
Jonsson A, Berg S, Quttineh NH … +1 more , Jonsson T
Ecol Appl · 2025 Dec · PMID 41416349 · Full text
Biodiversity is highly affected by ecological processes at the landscape level. To facilitate management decisions at a landscape level, we present an end-user-oriented framework that assesses the biodiversity capacity o...
Biodiversity is highly affected by ecological processes at the landscape level. To facilitate management decisions at a landscape level, we present an end-user-oriented framework that assesses the biodiversity capacity of individual biotopes in a fragmented landscape and ranks the importance of the biotope patches. The framework can be applied to any biotope and landscape. Analyses can further be done on planned or predicted future scenarios and changes in the landscape structure. There has been continuous exchange with stakeholders and case study testing with the purpose to build a tool that answers the important questions of end users, and provides results that are useful for decision-makers and environmental managers in environmental management and land use planning. The framework is novel in its calculations of the combined effects of connectivity and survival of biodiversity in the biotope patches. It uses land cover data and the concept of umbrella focal species as input. The framework strongly builds on ecological theory and ecological modeling, and produces three outputs of interest: a heatmap visualizing individual patch importance for upholding landscape biodiversity, an indicator metric of the ability of a biotope landscape to support biodiversity, and the number of unsustainable individual patches. The theoretical foundation and structure of the framework are thoroughly explained. The use of its output is further demonstrated by one selected case study where the calculations are applied to a biotope of fragmented old coniferous forest in Sweden. We additionally examine and show how the overall biodiversity potential of the biotope landscape is dependent on which types of species communities are in focus by applying different umbrella focal species. The case study demonstrates the importance of landscape structure for sustainable biodiversity. Results further demonstrate that it is essential to consider the type of species community that is the primary biodiversity conservation target.
Unraveling multipredator impacts in salmon-bearing rivers using quantitative DNA metabarcoding.
Winkowski JJ, Crosson LM, Olden JD
Ecol Appl · 2025 Dec · PMID 41414652 · Full text
Ecological impacts of invasive species are mounting as their numbers and geographic extent continue to increase. Across extensive parts of their range, Pacific salmon (Oncorhynchus spp.) smolts face an expanding gauntlet...
Ecological impacts of invasive species are mounting as their numbers and geographic extent continue to increase. Across extensive parts of their range, Pacific salmon (Oncorhynchus spp.) smolts face an expanding gauntlet of nonnative predators during their seaward migration. Adopting multispecies, spatiotemporal perspectives is essential for understanding direct and indirect predation risks and prioritizing management actions seeking to reduce impacts. Using quantitative DNA metabarcoding, we investigated trophic interactions of commonly co-occurring nonnative and native fish predators of Pacific Northwest, USA, salmon-bearing rivers, addressing challenges for salmon recovery and questions related to single-species management. Chinook salmon (Oncorhynchus tshawytscha) were frequently consumed by nonnative smallmouth bass (Micropterus dolomieu), largemouth bass (Micropterus salmoides), rock bass (Ambloplites rupestris), and native northern pikeminnow (Ptychocheilus oregonensis). Among the focal predators, Chinook salmon were the largest contributors to smallmouth bass diets, ranking as their second most important prey. Chinook salmon consumption peaked during a year of relatively high smolt abundance, low discharge, and warm stream temperatures. The following year, under opposite conditions, Chinook salmon consumption declined, though predation remained disproportionately high in certain mainstem and tributary regions. Native species of conservation concern were frequently consumed by nonnative predators, including imperiled native lamprey (family Petromyzontidae). Across space and time, native prickly sculpin (Cottus asper) and largescale sucker (Catostomus macrocheilus) were generally the highest contributing prey for nonnative predators. Intraguild predation was prevalent, most notably with smallmouth bass as the top prey for northern pikeminnow. Intraguild predation highlights potential risks of compensatory effects when predators are managed in isolation. Our study provides crucial insights into restoring food webs for native species while minimizing the likelihood of compensatory effects and demonstrates the value of quantitative DNA metabarcoding for understanding novel predator assemblages. As ecosystems worldwide face increasing pressures from co-occurring invasive species, integrating multispecies approaches into management strategies is essential for mitigating impacts and conserving biodiversity.
Method matters: Use of thermal-imaging drones to assess the assumptions of density estimation techniques.
Delaney DM, Harms TM, Dinsmore SJ
Ecol Appl · 2025 Dec · PMID 41361843 · Full text
Techniques to estimate the density of unmarked animals are widely used by ecologists, but accurate estimates from these methods rely on assumptions about the study system. We conducted thermal-imaging drone surveys to te...
Techniques to estimate the density of unmarked animals are widely used by ecologists, but accurate estimates from these methods rely on assumptions about the study system. We conducted thermal-imaging drone surveys to test the validity of three assumptions for conducting distance sampling on white-tailed deer (Odocoileus virginianus) via nocturnal spotlight surveys in Iowa, USA. We found that the proportion of the population that occurred within forests that are unsamplable (i.e., availability bias) was negligible when vegetative green-up was sparse but increased to more than 50% as spring green-up progressed. The proportion of deer that were bedded, which are less detectable than standing or walking deer, depended on the day of year and time of night, suggesting these variables should be modeled on detection probability to reduce bias in parameter estimates. Lastly, we found evidence of road avoidance which influences how we analyze distance sampling data from road-based survey designs. Each of these deviations from the assumptions of conventional distance sampling informs future sampling design and analysis and will improve the accuracy of density estimates in our system. More generally, our study provides an example of how drone surveys can be conducted to improve density estimation techniques for a range of animal systems.
Impacts of land use on bird communities in the Western Himalaya: Insights from a two-decade-long monitoring program.
Srinivasan S, Thinley T, Gurmet K … +2 more , Mishra C, Suryawanshi KR
Ecol Appl · 2025 Dec · PMID 41358553 · Publisher ↗
Anthropogenic land use change due to farming and livestock grazing has altered biodiversity composition greatly in ecosystems around the world. This is especially true in grasslands and rangelands; however, these ecosyst...
Anthropogenic land use change due to farming and livestock grazing has altered biodiversity composition greatly in ecosystems around the world. This is especially true in grasslands and rangelands; however, these ecosystems in high-altitude regions remain understudied. Moreover, anthropogenic effects in these habitats in the long term remain poorly understood. We studied bird densities and composition across four different habitats along a gradient of intensity of land use (crop fields, grazed meadows, grazed steppe, and ungrazed steppe), in the Trans-Himalayan region of Spiti Valley in Himachal Pradesh, India. Started in 2002, this continuing study is one of the longest running bird monitoring programs in India. We found that bird community composition differed significantly along the land use intensity gradient. Although crop fields had the highest bird densities, the bird community here was homogenized, comprising mainly habitat generalist species. Ungrazed steppe harbored more habitat specialist species and high bird densities. Grazed habitats were generally unfavorable for birds, with lower densities and possibly lower species richness. Decadal changes in densities revealed declines in the least used ungrazed steppe habitat, highlighting a possible role of climate change. Our study underscores the importance of land use type in affecting avifauna in the Trans-Himalaya. Holistic land management practices, including continuing traditional (organic) farming and maintaining ungrazed patches in grazed rangelands, could help maintain coexistence between biodiversity and people in these multiuse landscapes.
Early channel evolution relates to fish community resource use in the Gulf Coastal Plains of North America.
Stearman LW, Schaefer JF, Clark S
Ecol Appl · 2025 Dec · PMID 41358544 · Publisher ↗
Recent work has highlighted the importance of complex, multi-threaded, sediment, and wood-retentive channels ("stage 0" channel morphology). Widespread channel evolution from a variety of perturbations threatens these cr...
Recent work has highlighted the importance of complex, multi-threaded, sediment, and wood-retentive channels ("stage 0" channel morphology). Widespread channel evolution from a variety of perturbations threatens these crucial habitat types by shifting river channels to higher energy, more erosive environments. In this paper, we expand our understanding of the effects of loss of these resources with a quantitative, multi-decadal dataset of fish and habitats across National Forest sites in the Gulf Coastal Plains of Mississippi. Channel morphological analysis indicated a gradient from incised, wide, shallow channels with coarse substrates typical of advanced channel evolution processes to relatively unincised, narrower, deeper, more sediment, and wood-retaining channels typical of stage 0 conditions. Multivariate analysis of community-scale resource use suggested a gradient from communities which predominately use resources available in more erosive channels to those found in more stage 0-type channels. Regional constrained ordination, intra-watershed meta-analyses, and inter-watershed aggregate analyses all linked the channel morphology erosion gradient to community-scale resource use gradients. Measures of functional versus taxonomic diversity suggest a loss of functional but not taxonomic diversity. Our results demonstrate links between resource types available in channels and how communities structure themselves based on resource use. Further, our results suggest that this initial stage of channel evolution has a different outcome than later stages, which filter out habitat specialists in favor of generalist species. We integrate existing studies of fish community response to channel evolution with our data to build a broader understanding of the process and its ecological impacts in the Mississippi Embayment. Our results have implications for biodiverse and imperiled fish faunas globally.
Seasonal effects of farmer-managed livestock grazing exclusions on bird communities in Burkina Faso.
Quintas I, Marcacci G, Zongo AN … +6 more , Korner P, Kuttnig A, Spaar R, Diakité B, Kaguembèga-Müller F, Jacot A
Ecol Appl · 2025 Dec · PMID 41358538 · Full text
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....
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.
Projecting the future of a threatened marine mammal in relation to climate warming.
Regehr EV, Quakenbush L, Von Duyke AL … +2 more , Citta JJ, Lindsay JM
Ecol Appl · 2025 Dec · PMID 41358521 · Full text
Climate warming is expected to impact global biodiversity, especially in the rapidly warming Arctic. There is an urgent need to evaluate the demographic effects of climate warming under different greenhouse gas emission...
Climate warming is expected to impact global biodiversity, especially in the rapidly warming Arctic. There is an urgent need to evaluate the demographic effects of climate warming under different greenhouse gas emission pathways to guide wildlife management and inform listing decisions under protected species legislation. We used forecasted environmental variables to drive a novel demographic model for the ringed seal (Pusa hispida), a circumpolar Arctic marine mammal and critical subsistence resource for Indigenous people. Under the most demographically plausible conditions and assumptions, the projected abundance of ringed seals in the Chukchi Sea west of Alaska, USA, changed by an average of -7% (range -25% to 4%) by 2058 and -71% (range -96% to -8%) by 2100. The choice of greenhouse gas emissions pathway was the most important determinant of population outcomes through its influence on two habitat variables, snow-on-ice depth and sea-ice area. The choice of climate model, the intrinsic population growth rate, density dependence, and polar bear predation had a moderate influence on population projections, while harvest by Alaska Natives had a small influence. Modeling results suggest that ringed seals in the Chukchi Sea can exhibit stable or increasing recruitment at average April snow-on-ice depths below 20-30 cm. Given that declining snow depth was central to listing the species as threatened under the U.S. Endangered Species Act, our work both represents the first quantitative investigation of future abundance for Alaskan ringed seals and is relevant to conservation assessments for the species.
Shrub-facilitated invasion accelerates desertification.
Lucero JE, Lortie CJ, Filazzola A … +1 more , Callaway RM
Ecol Appl · 2025 Dec · PMID 41358520 · Full text
In theory, increasing sensitivity of primary productivity to precipitation variability is a biophysical symptom of dryland degradation, or "desertification," but empirical tests of this in the context of biological invas...
In theory, increasing sensitivity of primary productivity to precipitation variability is a biophysical symptom of dryland degradation, or "desertification," but empirical tests of this in the context of biological invasions are scant. To test the potential for exotic grass invasion to exacerbate biophysical symptoms of desertification, we measured the biomass and biodiversity of herbaceous plant assemblages along a 41-248 mm/year precipitation gradient across the Mojave and San Joaquin Deserts within communities at high versus low levels of exotic grass invasion and under shrub canopies versus interstitial space, over 5 years. Exotic grass invasion doubled the conversion rate of precipitation into biomass, and native shrubs increased ecosystem sensitivity to precipitation through strong facilitation of exotic grasses. Invasion-driven increases in biomass production corresponded to significant decreases in native biodiversity. We propose that shrub facilitation of exotic grasses accelerated desertification by promoting a non-native flora that is highly sensitive to precipitation variability and strongly linked to biodiversity degradation. Suppressing exotic grasses and managing facilitated invasion will help mitigate desertification.
Integrating molecular methods and biophysical modeling to assess functional connectivity between marine protected areas.
Beng KC, Akimova A, Laakmann S … +17 more , Sidorenko V, Rubinetti S, Pineda-Metz SEA, Pogoda B, Brand SC, Klemm K, Wegner KM, Shama LNS, Schmittmann L, Gimenez L, Alter K, Stechele B, Rahdarian A, Winter C, Androsov A, Sokolova I, Sell AF
Ecol Appl · 2025 Dec · PMID 41358516 · Full text
Marine protected area (MPA) networks are important for supporting biodiversity, enhancing ecosystem resilience, and facilitating species recovery. For the effectiveness of conservation and restoration, functional connect...
Marine protected area (MPA) networks are important for supporting biodiversity, enhancing ecosystem resilience, and facilitating species recovery. For the effectiveness of conservation and restoration, functional connectivity plays a vital role. The dispersal, movement, and successful establishment of organisms between suitable habitats and MPAs ensure long-term sustainability of the populations. Despite its importance, functional connectivity is rarely integrated into restoration planning, which limits the effectiveness of species reintroductions, habitat connectivity, and adaptation to environmental changes. In this study, we applied an integrative approach combining molecular detections (environmental DNA [eDNA] and meroplankton metabarcoding) with biophysical modeling to explore the functional connectivity between two Natura 2000 MPAs in the North Sea: Borkum Reef Ground (BRG) and Sylt Outer Reef (SOR). We focused on the European flat oyster (Ostrea edulis), a reef-building species that once provided vast reef habitats but is now functionally extinct in the German Bight and is therefore the subject of recent restoration measures at BRG. Our results showed partial but informative correspondence between molecular detections of oyster genetic traces and the modeled larval pathways during the June-July 2022 sampling period. We further explored larval dispersal across entire spawning seasons in 2022 and 2023. Connectivity between BRG and SOR was highly dependent on larval drift depth. Surface-drifting larvae showed strong interannual variability, with 3% reaching SOR in 2022 when northwesterly winds dominated, increasing to 22% in 2023 under westerly and southwesterly winds. Larvae drifting at depth, however, exhibited near-zero connectivity, leading to high self-recruitment rates, with over 25% settling near the original restoration sites. Our results demonstrate that wind-driven currents are a key driver of interannual variability in larval retention and dispersal. Additionally, they highlight the role of biological traits, such as vertical positioning and pelagic larval duration, in shaping connectivity between MPAs and oyster restoration sites. These findings emphasize the need to integrate connectivity assessments into MPA management and the restoration planning of reef-building benthic species. The interdisciplinary approach presented here provides a quantitative framework for assessing connectivity under species- and site-specific conditions, offering a transferable tool to evaluate the restoration potential of other species and enhance the functional network between MPAs.
Dispersal can spread management benefits: Insights from a modeled Fijian coral reef network.
Greiner A, Andrello M, Krkošek M … +6 more , Fortin MJ, Nand Y, Jupiter SD, Mangubhai S, Wenger A, Darling ES
Ecol Appl · 2025 Dec · PMID 41358513 · Full text
The combined effects of coral and macroalgal propagule dispersal, local bistability dynamics and pressures that span the land-sea interface are not well understood, and consequently, are not well accounted for in coral r...
The combined effects of coral and macroalgal propagule dispersal, local bistability dynamics and pressures that span the land-sea interface are not well understood, and consequently, are not well accounted for in coral reef management planning. In particular, fishing and sedimentation from nearby watersheds can tip reefs from coral-dominated stable states to macroalgal-dominated stable states. To address these knowledge gaps, we developed a mathematical model of the benthic cover dynamics of a 75-Reef network in Fiji to compare the effectiveness of three different management intervention types: extending the area of periodic fishery closures to encompass more reefs (modeled by increasing herbivore grazing rates; managing a sea-based pressure), improving water quality across Fiji (modeled by decreasing coral mortality rates; managing a land-based pressure) and the two interventions combined (managing land and sea-based pressures simultaneously). We ran the model with three grazing scenarios (low, medium, high) to account for uncertainty in actual herbivore grazing rates among reefs, as well as to represent regimes of macroalgal-dominated, bistable and coral-dominated dynamics in isolated reefs. Our results indicate that the presence of connectivity in the model stabilized the dynamics, with the final benthic cover and management effects exhibiting almost no sensitivity to initial conditions under the medium grazing scenario. The model predicts that the integrated land-sea management is the most effective management intervention for ensuring high coral cover (>30%). We also find that fishery closure management that improves the grazing rate in less than half of the reef network can lead to increases in coral cover across the entire reef network. This result suggests that, as long as a few reefs in the network have high grazing, reefs across the network may trend to high coral cover as long as environmental conditions do not change. Based on an expected value of perfect information analysis, we find that the effectiveness of the integrated land-sea management intervention is robust to the three grazing scenarios and suggests that this model can inform management decisions even with uncertainty. These findings advance our understanding of how a network of ecosystem patches with local bistability could behave and informs their management.
Keystone communities can rescue aquatic metacommunities influenced by pesticide contamination.
Vieira CB, Barbosa GP, Dos Santos AC … +9 more , Lara N, Mateus-Barros E, Portinho JL, Sarmento H, Perbiche-Neves G, Montagner CC, Schiesari L, Saito VS, Siqueira T
Ecol Appl · 2025 Dec · PMID 41358512 · Full text
Pesticide contamination in freshwater habitats is a major global issue, affecting water quality, biodiversity, and ecosystem services. Uncontaminated habitats embedded in agricultural landscapes might act as keystone com...
Pesticide contamination in freshwater habitats is a major global issue, affecting water quality, biodiversity, and ecosystem services. Uncontaminated habitats embedded in agricultural landscapes might act as keystone communities, with the ability to restore diversity and ecological processes in contaminated sites through dispersal. Despite their potential relevance, the role of keystone communities in mitigating agrochemical contamination remains untested. We asked if pristine habitats embedded in agricultural landscapes can act as keystone communities and drive the recovery of contaminated habitats. To answer this question, we conducted a mesocosm experiment to simulate zooplankton metacommunity dynamics under three treatments: uncontaminated, fully contaminated, and partially contaminated metacommunities. We examined communities over time following dispersal and pesticide contamination to analyze their trajectories, diversity, and recovery capacity. Analyses were conducted for all species, as well as for Cladocera and Copepoda separately, at both local (individual communities) and regional scales (three communities linked by dispersal-i.e., metacommunities). Taxon-specific population trajectories indicated that cladoceran densities increased across treatments irrespective of contamination, whereas copepods exhibited species-level declines or increases under local pesticide exposure. These taxon-specific population responses to contamination altered community trajectories, resulting in a greater loss of species in completely contaminated metacommunities. Metacommunities with uncontaminated habitats partially recovered from contamination and showed compositional and gamma diversity patterns comparable to uncontaminated metacommunities. Recovery patterns differed across Cladocera and Copepoda, with recovery being more evident at the regional scales. Keystone communities had a greater influence on the recovery of Cladocera community composition and on Copepoda gamma diversity. Our results supported the prediction that keystone communities play a fundamental role in local and regional dynamics of aquatic metacommunities inserted in landscapes with a heterogeneous structure of contamination. Positioning preserved habitats well connected to impacted sites could allow a quick colonization after pesticide contamination, recovering the system until the next crop management cycle. However, taxon-specific trajectories underscore the need to consider functional and dispersal traits when designing mitigation strategies. We thus suggest a metacommunity perspective for better predictions of risks associated with pesticide use in nature and ways of mitigating them.
Optimizing seagrass planting arrangements for animal benefits in a multihabitat restoration seascape.
Sievers M, Brown CJ, Rasmussen JA … +6 more , Nielsen B, Steinfurth RC, Flindt MR, Banke TL, Gilby BL, Connolly RM
Ecol Appl · 2025 Dec · PMID 41358505 · Full text
Restoring lost and degraded ecosystems to enhance biodiversity and ecosystem services is a global priority, and animal responses to the restoration of habitats are a critical but undervalued component. Identifying the ke...
Restoring lost and degraded ecosystems to enhance biodiversity and ecosystem services is a global priority, and animal responses to the restoration of habitats are a critical but undervalued component. Identifying the key drivers of animal colonization in restored habitats provides critical insights for restoration practitioners seeking to maximize ecological outcomes. When integrated into predictive frameworks and spatial decision-support tools, this knowledge becomes valuable for strategic planning, particularly in complex multihabitat restoration projects where spatial configuration remains a crucial yet understudied dimension influencing ecosystem recovery trajectories. We collect and analyze animal data from one of the world's largest multihabitat coastal restoration systems in Denmark, comprising restored seagrass (Zostera marina), boulder reefs, and mussel reefs. Using fine-scale spatial patterns in population abundances, we develop spatially explicit predictions across the seascape for various seagrass restoration scenarios and produce a series of optimizations. We consequently demonstrate that it is practical to configure restoration to optimize biodiversity objectives, including those linked with fished species. Species-specific responses translated to variable outcomes across restoration scenarios and optimizations. While the optimal number and arrangement of restored patches varied depending on the target species or species group (e.g., fisheries species or seagrass specialists), one near-ubiquitous arrangement was patchy seagrass planting. This aligns with current practice in the region, maximizes restoration efficiency and highlights the importance of not homogenizing seascapes for biodiversity. Our approach provides a practical framework for incorporating animal monitoring data into restoration planning, helping practitioners design and optimize spatial planting configurations to achieve specific ecological objectives.
Remote sensing and foraging data illustrate landscape-scale considerations for coastal restoration and avian management.
Geary B, James WR, Karubian J … +2 more , Nelson JA, Leberg PL
Ecol Appl · 2025 Dec · PMID 41358502 · Full text
As coastal restoration projects around the world continue to grow in scale and frequency, it is critical to consider how modified landscapes support wildlife species of concern and broader ecosystem function. In the nort...
As coastal restoration projects around the world continue to grow in scale and frequency, it is critical to consider how modified landscapes support wildlife species of concern and broader ecosystem function. In the northern Gulf of Mexico, particularly coastal Louisiana, maintenance of barrier islands serves to protect inland human settlements, and provide critical breeding habitat for many waterbird populations. To remain productive, colonies must also be linked to high-quality marine foraging areas, though these relationships are rarely evaluated in active restoration areas. To demonstrate how this linkage can be evaluated in dynamic environments at a regional scale, we coupled remote sensing and stable isotope data to generate maps of energetic importance for Gulf menhaden (Brevoortia patronus), one of the most ecologically and economically important fish species in the northern Gulf. We then overlaid these maps with foraging movement data from brown pelicans (Pelecanus occidentalis) nesting at three of the largest remaining colonies in the state to assess how a novel characterization of their prey distribution matched individual bird movements. We found that the quality of foraging habitat (i.e., menhaden resource quality) had a significant influence on space use decisions of pelicans over space, time, and multiple scales of movement, as well as strong spatial segregation between colonies, highlighting the importance of island placement when considering restoration priorities and wildlife response. Our results show the considerable potential that "E-scapes" hold as a valuable tool for future restoration planning, with utility in assessment of coastal ecosystem function from a spatially explicit, multi-trophic perspective.
The combined effects of multiple stressors in an endangered, long-lived species: Lessons learned and ways forward.
Pirotta E, Tyack PL, Adams J … +30 more , Asaro MJ, Bouchet PJ, Crocker DE, Durban JW, Hall AJ, Harris CM, Knowlton AR, Kraus SD, Lehoux C, Linden DW, Good CP, Meyer-Gutbrod E, Miller AS, Miller CA, Miller PJO, Moore MJ, Orphanides CD, Patterson EM, Pettis HM, Photopoulou T, Plourde S, Record NR, Redfern JV, Roberts JJ, Schick RS, Shank B, Solinger L, Southall BL, Trego ML, Thomas L
Ecol Appl · 2025 Dec · PMID 41358499 · Full text
Exploring solutions to expanding industrial activities and climate change requires assessments of the combined effects of multiple stressors on wildlife populations. We present a spatially explicit state-space model for...
Exploring solutions to expanding industrial activities and climate change requires assessments of the combined effects of multiple stressors on wildlife populations. We present a spatially explicit state-space model for the health, survival, reproduction, and somatic growth of individuals in a long-lived, wide-ranging species. The model is applied to critically endangered North Atlantic right whales (Eubalaena glacialis) to investigate the combined effects of three primary stressors affecting the species' viability: entanglements in fishing gear, vessel strikes, and prey availability. We estimate exposure to these stressors in space and time and assess how their effects may combine in the pathway from exposure to vital rates. Results suggest that changes in whale distribution after 2010 led to increased entanglement risk. Poorer prey conditions were associated with an increased effect of carrying fishing gear, but, overall, results on combined effects were not conclusive and depended on model formulation. We also incorporated the estimated effects of stressors into a population viability analysis to explore alternative scenarios of stressor reduction. This integrated analysis highlighted the importance of the declining trend in maximum body length and its effect on reproduction, in addition to the documented impact of entanglements on survival. Model development and application elucidated critical data needs and the influence of underlying mechanistic assumptions. Specifically, models for the combined effects of stressors hinge on the availability of extended longitudinal measurements of individual health and life history outcomes, extensive datasets on the spatiotemporal distribution of stressors, and information on individual space use affecting rates of exposure to stressors. Lessons from this data-rich case study will support the generalization of the modeling approach to other long-lived species where measuring the population-level consequences of multiple stressors directly is unfeasible.
Restoration of formerly afforested blanket bog: Estimating time for vegetation recovery.
Rydgren K, Andersen R, Halvorsen R … +5 more , Hancock MH, Hughes RD, Martin-Walker A, Töpper JP, Cowie N
Ecol Appl · 2025 Dec · PMID 41358498 · Full text
Peatland restoration aims to restore hydrology and peat-forming vegetation, supporting other ecosystem functions. However, the time required for complete vegetation recovery is generally unknown. Here, we investigate thi...
Peatland restoration aims to restore hydrology and peat-forming vegetation, supporting other ecosystem functions. However, the time required for complete vegetation recovery is generally unknown. Here, we investigate this in an experimentally restored, formerly afforested blanket bog in northern Scotland, which was plowed, fertilized, and planted with non-native conifers in the mid-1980s. Plowing created three "microforms": Ridges, Original surface, and Furrows. Restoration management took place in two stages: trees were felled and drains blocked in 1998 (Standard treatment); then parts of the area were further rewetted with additional drain-blocking in 2015/2016 (Enhanced treatment). We recorded plant species composition in permanent quadrats 0, 5, 13, and 24 years after the start of restoration. Here we use an ordination-regression-based approach (ORBA) to predict time to plant species compositional recovery compared with a reference (comparable nearby intact blanket bog). For the first 13 years, plant species composition diverged from the reference, then later started to converge. If the current speed and direction of vegetation change were maintained, predicted time to recovery varies between 50-100 years and 120-285 years applying a relaxed or strict criterion for restoration success, respectively. Seven growing seasons after Enhanced treatment, recovery speed increased only for the driest microform, Ridge. Surprisingly, this microform was not predicted to take longer to recover than other microforms under either treatment. On the landscape scale, sloping areas were harder to restore than flatter areas, having longer predicted times to recovery. Complete vegetation restoration may take a long time because of legacies from the afforestation (e.g., increased nutrient availability) and the time taken to fully restore surface morphology and water table. On the other hand, other research has already demonstrated that the site is currently acting as a net carbon sink, despite the incomplete vegetation recovery. We argue that functions may be restored without full recovery of species composition. However, approaching the full suite of species may be desirable to support long-term resilience. Successful peatland restoration needs a strong science-practice partnership, where learning gained from monitoring both damaged and comparable intact peatlands can be used to adapt management interventions.
The role of bison (Bison bison) herbivory in the function of semi-arid grasslands of Arizona.
Musto DT, Schoenecker KA, Knapp AK … +2 more , von Fischer JC, Aldridge CL
Ecol Appl · 2025 Dec · PMID 41358495 · Full text
The American Plains Bison (Bison bison) is recognized as a grassland keystone species; however, their effect on grassland ecosystem function can vary widely among different plant communities, ranging from degradation to...
The American Plains Bison (Bison bison) is recognized as a grassland keystone species; however, their effect on grassland ecosystem function can vary widely among different plant communities, ranging from degradation to enhancement. Grazing dynamics, environmental conditions, and the capacity for plants to compensate for losses due to herbivory largely govern the degree and magnitude of herbivory-induced ecosystem change, making it challenging to manage grazing ecosystems. Here, we examine how different grazing intensities and environmental conditions affect aboveground herbaceous production and herbaceous nitrogen yield within high-elevation, semi-arid grasslands of the Grand Canyon ecosystem in northern Arizona, United States. We conducted a replicate herbivore exclusion experiment in grassland meadows using both long-term exclosures (0.40 ha) and temporary grazing exclusion cages (1 m) to quantify herbaceous production and nitrogen yield in sites with high bison density (Grand Canyon National Park) and low bison density (Kaibab National Forest). Our goal was to assess the influence of bison grazing on aboveground herbaceous production, the relationship between herbaceous consumption (offtake) and production, and evaluate potential differences in herbaceous nitrogen yield. We found that bison grazing enhanced herbaceous production 1.32-fold and nitrogen yield 1.61-fold, regardless of grazing intensity, availability of soil nutrients, or spatiotemporal variation in climate during our study. Although we expected herbaceous production to decline at the highest levels of herbaceous offtake, we observed a linear positive relationship between offtake and production in Grand Canyon. Over the 2-year study, bison grazing was the primary influential factor explaining variation in grassland production compared to other environmental variables (i.e., temperature, precipitation, and soil nutrients). Our results show no evidence of degradation in aboveground plant productivity, which is an important metric of ecosystem function, from the current dynamics of bison herbivory in the grasslands of the North Rim of Grand Canyon National Park.
Rice cultivation supports growth and survival of a threatened semi-aquatic reptile.
Rose JP, Nguyen AM, Jordan AC … +7 more , Macias DA, Schoenig EJ, Napolitano GR, Kim R, Ersan JSM, Fulton AM, Halstead BJ
Ecol Appl · 2025 Dec · PMID 41358494 · Full text
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 wh...
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 and season drive scavenging dynamics in livestock-rewilded landscapes.
Daza RR, Acebes P, Olea PP
Ecol Appl · 2025 Dec · PMID 41358491 · Full text
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 com...
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.
Large, prolonged flooding and pool persistence promote floodplain fish diversity in a threatened river.
Pratt OP, Beesley LS, Gwinn DC … +5 more , Tayer TC, Pusey BJ, Keogh CS, Setterfield SA, Douglas MM
Ecol Appl · 2025 Oct · PMID 41290353 · Full text
While it is widely recognized that reduced river-floodplain connectivity has contributed to the decline of biodiversity in floodplain rivers, surprisingly few studies have quantified the relationship between connectivity...
While it is widely recognized that reduced river-floodplain connectivity has contributed to the decline of biodiversity in floodplain rivers, surprisingly few studies have quantified the relationship between connectivity, pool persistence, and fish assemblage structure to the level required to generate measurable targets for management. The task is further complicated by the inherent complexity of accurately describing fish assemblages. We maximized our capacity to describe unbiased hydrology-fish relationships by sampling fish assemblages in floodplain pools with a variety of connection histories (60 sampling events), and by using a hierarchical multispecies occupancy model that accounts for changes in sampling design and species detection. Our study was conducted in a tropical wet-dry river threatened by water resource development and elevated temperatures associated with climate change, the Fitzroy River (Western Australia). Our results revealed that wet season (river-floodplain connectivity) and dry season (pool persistence) components of the hydrological cycle influenced fish occurrence in floodplain pools. Pools that were connected to the river by short distances were substantially more species rich than distal pools. This effect was strong at distances <2000 m but negligible at distances greater than 3000 m. Species richness in floodplain pools increased when wet season connection to the river lasted more than 25 days, and when river stage height exceeded 6 m. Prolonged connection to the river (up to 90 days) during overbank flooding (river stage height >11 m) maximized fish species richness in floodplain pools. Dry season components of the hydrological cycle also influenced fish assemblage structure, with pools that persisted during the preceding dry season twice as species rich as those that dried. Our model revealed that sampling gear influenced species detectability, indicating that accounting for variable detection is critical when assessing fish assemblage structure. Given that large flood events are less likely to be impacted by water take, we recommend that managers seeking to maintain floodplain fish diversity ensure that water resource development does not negatively impact pool persistence during the dry season.
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