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Estuaries include some of the most productive yet anthropogenically impacted marine ecosystems on the planet, and provide critical habitat to many ecologically and economically important marine species. In order to elucidate ecological function in estuaries, we must understand what factors drive community dynamics. Delaware Bay is the third largest estuary in the United States and hosts over 200 species of migrant and resident fishes and invertebrates. The Delaware Division of Fish and Wildlife has conducted two long-term trawl surveys at monthly intervals in Delaware Bay since 1966. The two surveys collect data on environmental conditions, species composition, and number of fishes and macroinvertebrates across different size classes and life histories. Using a suite of multivariate approaches including hierarchical cluster analysis, canonical correlation analysis, and permutational multivariate analysis of variance, we characterized the fish and macroinvertebrate community in Delaware Bay and found that community composition and environmental conditions varied across spatial and seasonal scales. We identified four distinct biogeographic regions, based on environmental conditions and community composition, which were consistent across surveys. We found that the community was driven primarily by gradients in temperature and salinity and that abundant, frequently occurring species in the Bay have well-defined environmental associations. Our work represents the first attempt to use an existing historical survey to better understand how environmental parameters influence diversity and distribution of macrofauna within Delaware Bay, providing insight into how abiotic variables, influenced by climate, may impact the Delaware Bay ecosystem and similar estuarine ecosystems worldwide.

When non‐native species invade ecosystems, coevolved plant–animal interactions and associated ecological functions are altered, often to the detriment of local biodiversity. While mutualistic interactions can benefit from—and assist with—ecological restoration through the removal of non‐native species, community‐level changes in antagonistic interactions due to restoration are less well understood. Insect seed predators provide important ecosystem functions, but can also have antagonistic effects through pre‐dispersal seed predation which can cause fruit abortion or premature fruit drop, potentially affecting plant community composition. Here, we used a network approach and data on trophic interactions from a large‐scale field experiment to investigate the differences in insect seed predator communities between native restored sites (where non‐native plants were removed) and unrestored sites dominated by non‐native plants on the island of Mahé, Seychelles. Restored sites contained more individuals and species of seed predators (up by 81% and 50% respectively), and experienced a greater predation intensity (1.06 ± 0.53 vs. 0.27 ± 0.09), and predator specialisation compared to unrestored sites. The proportion of predated samples was similar between treatments (~14%). Beta diversity, measured as species and interaction turnover, increased at restored sites. Synthesis and applications: Our findings imply that vegetation restoration generates marked biodiversity benefits on native seed predator communities and their interactions. However, removing non‐native plants did not result in the elimination of non‐native seed predators, which might require targeted control measures. Our results highlight the importance of considering the effects of restoration on antagonistic interactions, in addition to those reported for pollination and seed dispersal services. Management practices should aim to control plant invasions for the conservation of native plant communities that serve as resources and refugia both for mutualists (e.g., seed dispersers and pollinators) and native insect seed‐predator antagonists, both of which benefit native ecosystem function. [ABSTRACT FROM AUTHOR]

Ongoing habitat loss and species extinctions require managers to implement and quantify the effectiveness of conservation actions for protecting biodiversity. Fencing, when done properly, is an important management tool for conservation in landscapes where wildlife and domestic animals co‐occur, potentially enhancing habitat use through selective exclusion of domestic species. For instance, the fencing of forest patches in the Neotropics is expected to reduce the degradation of understory vegetation by cattle, releasing these resources for the native community of browsers and fruit consumers. Here, we implemented an ecological experiment using a before‐after control‐impact design to quantify the effect of cattle exclusion on encounter probability of the native community of browsers and fruit consumers, and percent ground cover in multifunctional landscapes of the Colombian Orinoquía. We built 14 km of wildlife‐permeable fences along forest edges in four forest patches (i.e. blocks) containing control and fenced (treatment) sites. We installed 33 camera traps to obtain information about wildlife and cattle encounter probabilities, before and after the fences were constructed. We used Bayesian generalised linear mixed effects models to quantify the effect of fences via the interaction between the time period (before and after the fences were built) and treatment (control or fenced sites). Fencing was effective at reducing encounter probabilities of cattle in the treated sites, and it had a positive impact on relative encounter probabilities of four of seven studied wildlife species (herbivores including the black agouti [dry season only], lowland tapir [dry season only] and spotted paca [both seasons] and an omnivore, the South American coati [rainy season only]). The effect of fencing was negative for the collared peccary but only during the dry season. No statistically significant effect was detected for the white‐lipped peccary or white‐tailed deer. Synthesis and applications: We provide experimental evidence that fences are effective at selectively excluding cattle and increasing encounter rates of wild browsers and fruit consumers in forest patches where these species co‐occur with cattle. Our results highlight an important application of fencing ecology in Neotropical forests, where the implementation of wildlife‐permeable fences is feasible due to smaller body sizes of wildlife compared to domestic animals such as cattle. [ABSTRACT FROM AUTHOR]

Aquatic insects are key to wetland ecological functioning, and the distribution of amphibious insects such as Odonata jointly depends on environmental conditions in the aquatic and terrestrial settings. Therefore, untangling the relative effects of within‐wetland and landscape composition can help predict the responses of Odonata to environmental alterations in wetlands. Using data from 19 wetlands spanning over the southern Brazilian Pampa (center‐western Rio Grande do Sul state), we assessed the relative importance of water chemistry and land‐cover variables to the richness and composition of larval Odonata assemblages (and suborders Anisoptera and Zygoptera). Anisoptera richness decreased with pH and bare soil area. Water pH and areas of bare soil, mosaic of agricultural land use, and waterbodies land cover were the main drivers of Odonata and Zygoptera composition. Our results indicate that land cover is the main driver of the assemblage structure of larval Odonata, although a complex interplay of mechanisms associated with land conversion and water quality drive the distribution of larval Odonata in freshwater wetlands of the Brazilian Pampa. The major implication of our findings is that land cover modification is the major threat to Odonata distribution in Pampean wetlands, with potential impacts on the trophic structure and functioning of these ecosystems. [ABSTRACT FROM AUTHOR]

Invertebrates account for over 90% of all described species and provide crucial ecosystem services. Land clearing, including the removal of abiotic habitat features, threatens invertebrate biodiversity, making environmental restoration crucial for conservation. However, little is known about the effects of abiotic restoration compared to the restoration of biotic features. To determine if rock addition increased invertebrate biodiversity, we introduced 120 t of rocks to 10 sites across five grassland reserves in the Australian Capital Territory in a before‐after‐control‐impact design. We sampled invertebrates using pitfall traps before treatment in 2016 and after rock addition in 2019 (during record‐breaking drought). We recorded 29,164 individual invertebrates from 19 orders and undertook a functional trait‐based analysis of rock effects on the invertebrate community. No effects of rock addition were observed on the probability of occurrence, richness, diversity, community similarity, or abundance of any taxonomic or functional group. The abundance of snare‐building spiders and large ants was higher in the control plots at the end of the experiment. These abundance responses in 2019 did not differ from the control or treatment plots in 2016. Thus, some combination of drought and rock addition appears to have neutralized a positive temporal change that was evident without rocks. Despite a regionwide, replicated restoration effort and an extensive functional analysis of invertebrate communities, very little positive response to rock addition was recorded. Rock addition did not have a negative effect on grassland invertebrate biodiversity and may still be beneficial to the long‐term conservation and restoration of vertebrate and invertebrate communities. [ABSTRACT FROM AUTHOR]

Seasonal foliage display (leaf phenology) is a key determinant of ecosystem function. Variation in land surface phenology, observed via space‐borne remote sensing, can be explained at broad spatial scales by climate, but we lack understanding of how vegetation structure and floristic diversity mediates these relationships. This lack of understanding hampers our ability to predict changes in phenology and therefore ecosystem function, in light of rapid ongoing shifts in biodiversity and ecosystem structure due to land use and climate change.We combined a network of 619 vegetation monitoring sites across seasonally dry tropical deciduous woodlands in Zambia with land surface phenology metrics to investigate the role of tree species diversity, composition and vegetation structure on patterns of land surface phenology, including the phenomenon of pre‐rain green‐up.Tree species diversity was associated with earlier pre‐rain green‐up, a longer growing season, and greater cumulative foliage production. Independent of diversity, proportional abundance of Detarioideae species (subfamily of Fabaceae) was associated with a longer growing season by facilitating earlier pre‐rain green‐up. Woodland stands with larger trees green up earlier, suggesting access to deep groundwater reserves. Senescence metrics showed variation among sites but were not well‐explained by precipitation, temperature, structure or diversity.Synthesis: Tree diversity, composition and structure are co‐determinants of seasonal patterns of foliage display in seasonally dry tropical deciduous woodlands, as measured via land surface phenology, at regional scale. Our study identifies both a niche complementarity effect whereby diverse woodlands exhibit longer growing seasons, as well as a mass‐ratio effect whereby detarioid species drive earlier pre‐rain green‐up, providing insights into the mechanisms underlying the biodiversity ecosystem function relationship in this biome. We stress the importance of considering biotic controls on ecosystem functioning in the next generation of earth‐system models predicting the response of communities to global change. [ABSTRACT FROM AUTHOR]

Compound effects of anthropogenic disturbances on wildlife emerge through a complex network of direct responses and species interactions. Land‐use changes driven by energy and forestry industries are known to disrupt predator–prey dynamics in boreal ecosystems, yet how these disturbance effects propagate across mammal communities remains uncertain. Using structural equation modeling, we tested disturbance‐mediated pathways governing the spatial structure of multipredator multiprey boreal mammal networks across a landscape‐scale disturbance gradient within Canada's Athabasca oil sands region. Linear disturbances had pervasive direct effects, increasing site use for all focal species, except black bears and threatened caribou, in at least one landscape. Conversely, block (polygonal) disturbance effects were negative but less common. Indirect disturbance effects were widespread and mediated by caribou avoidance of wolves, tracking of primary prey by subordinate predators, and intraguild dependencies among predators and large prey. Context‐dependent responses to linear disturbances were most common among prey and within the landscape with intermediate disturbance. Our research suggests that industrial disturbances directly affect a suite of boreal mammals by altering forage availability and movement, leading to indirect effects across a range of interacting predators and prey, including the keystone snowshoe hare. The complexity of network‐level direct and indirect disturbance effects reinforces calls for increased investment in addressing habitat degradation as the root cause of threatened species declines and broader ecosystem change. [ABSTRACT FROM AUTHOR]

Mountains exhibit a high degree of endemism and diversity, however, quantifying their biodiversity can be challenging. Similar to islands, species isolation in mountainous regions results in comparable patterns of evolution and extinction, rendering their biodiversity unique and highly susceptible to anthropogenic threats. The topographic relief in mountains plays a crucial role in creating habitat complexity, which in turn contribute to high plant diversity. Here, we investigated plant diversity in the volcano mountaintop vegetation on the Poços de Caldas Plateau, a region situated in the ecotone between the Atlantic Forest and Cerrado, characterized by natural radiation and significant anthropogenic intervention. We employed an automated approach through the filtering of georeferenced and non-georeferenced data to obtain a list of plant species in the region. Additionally, we statistically investigated the similarity among different high-altitude vegetations belonging to the campos de altitude from the Atlantic Forest and campos rupestres from the Cerrado. The plateau exhibits high plant diversity, including 1,659 specific and infraspecific taxa, especially belonging to Asteraceae and Poaceae. Our analyses suggest that geographical distance is a strong predictor of dissimilarity and that the Poços de Caldas Plateau is more floristically related to the campos rupestres, despite being associated with campos de altitude. The region possesses a unique set of biodiversity, indicating that it may be a distinct formation. Additionally, we hypothesize that Pleistocene events likely influenced the conformation of the current floristic composition in the region through species interchange between the Cerrado and Atlantic Forest. Our study also highlights the few taxa assessed for conservation status and anthropogenic threats that this habitat is facing. [ABSTRACT FROM AUTHOR]

The study of myxomycete biogeography has a long-standing history and has consistently drawn scholarly interest. Nevertheless, studies focusing specifically on the spatial and temporal distribution patterns of myxomycete diversity are relatively limited, with even fewer investigating the mechanisms driving the generation and maintenance of myxomycete diversity. Therefore, this study selected two geographically distant sampling sites within northern Chinese forests to investigate myxomycete species composition, community structure, environmental drivers, and assembly patterns under geographic barriers. We established plots in the Altai Mountains (ALE) and the Greater Khingan Mountains (GKM), gathered bark and litter, and conducted 80-day moist chamber cultures of myxomycetes. Additionally, myxomycete specimens were collected in the field simultaneously to supplement the data set. This study collected 541 myxomycete specimens belonging to 73 species from 28 genera, spanning 12 families and eight orders. The ALE and the GKM had 20 identical species, accounting for 27% of the total species. Myxomycetes from both regions exhibited abundant occurrence 18 days after cultivation, with the quantity on bark substrates notably higher than on litter. Arcyria pomiformis and Comatricha elegans were the most common species in moist chamber cultures. Mantel test outcomes revealed that environmental factors had no significant impact on myxomycete community similarity between the two areas, aligning with findings from the neutral community model analysis, indicating a predominant influence of stochastic processes on myxomycete community structure in moist chamber cultures. This study represents the first application of a quantitative framework to analyze myxomycete community assembly cultivated in moist chambers. [ABSTRACT FROM AUTHOR]

A pathogen arriving on a host typically encounters a diverse community of microbes that can shape priority effects, other within-host interactions and infection outcomes. In plants, environmental nutrients can drive trade-offs between host growth and defence and can mediate interactions between co-infecting pathogens. Nutrients may thus alter the outcome of pathogen priority effects for the host, but this possibility has received little experimental investigation. To disentangle the relationship between nutrient availability and co-infection dynamics, we factorially manipulated the nutrient availability and order of arrival of two foliar fungal pathogens (Rhizoctonia solani and Colletotrichum cereale) on the grass tall fescue (Lolium arundinaceum) and tracked disease outcomes. Nutrient addition did not influence infection rates, infection severity or plant biomass. Colletotrichum cereale facilitated R. solani, increasing its infection rate regardless of their order of inoculation. Additionally, simultaneous and C. cereale-first inoculations decreased plant growth and—in plants that did not receive nutrient addition—increased leaf nitrogen concentrations compared to uninoculated plants. These effects were partially, but not completely, explained by the duration and severity of pathogen infections. This study highlights the importance of understanding the intricate associations between the order of pathogen arrival, host nutrient availability and host defence to better predict infection outcomes. [ABSTRACT FROM AUTHOR]

Global migrations of diverse animal species often converge along the same routes, bringing together seasonal assemblages of animals that may compete, prey on each other, and share information or pathogens. These interspecific interactions, when energetic demands are high and the time to complete journeys is short, may influence survival, migratory success, stopover ecology, and migratory routes. Numerous accounts suggest that interspecific co-migrations are globally distributed in aerial, aquatic, and terrestrial systems, although the study of migration to date has rarely investigated species interactions among migrating animals. Here, we test the hypothesis that migrating animals are communities engaged in networks of ecological interactions. We leverage over half a million records of 50 bird species from five bird banding sites collected over 8 to 23 y to test for species associations using social network analyses. We find strong support for persistent species relationships across sites and between spring and fall migration. These relationships may be ecologically meaningful: They are often stronger among phylogenetically related species with similar foraging behaviors and nonbreeding ranges even after accounting for the nonsocial contributions to associations, including overlap in migration timing and habitat use. While interspecific interactions could result in costly competition or beneficial information exchange, we find that relationships are largely positive, suggesting limited competitive exclusion at the scale of a banding station during migratory stopovers. Our findings support an understanding of animal migrations that consist of networked communities rather than random assemblages of independently migrating species, encouraging future studies of the nature and consequences of co-migrant interactions. [ABSTRACT FROM AUTHOR]

The amount of genetic diversity within a population can affect ecological processes at population, community, and ecosystem levels. However, the magnitude, consistency, and scope of these effects are largely unknown. To investigate these issues, we conducted two experiments manipulating the amount of genetic diversity and environmental factors in larval amphibians. The first experiment manipulated wood frog genetic diversity, the presence or absence of caged predators, and competition from leopard frogs to test whether these factors affected survival, growth, and morphology of wood frogs and leopard frogs. The second experiment manipulated wood frog genetic diversity, the presence or absence of uncaged predators, and resource abundance to test whether these factors affected wood frog traits (survival, morphology, growth, development, and behavior) and other components of the ecological community (zooplankton abundance, phytoplankton, periphyton, and bacterial community structure). Genetic diversity did not affect wood frog survival, growth, and development in either experiment. However, genetic diversity did affect the mean morphology of wood frog tadpoles in the first experiment and the abundance and distribution of zooplankton in the second experiment. It did not affect phytoplankton abundance, periphyton abundance, or bacterial community structure. While effect sizes (Cohen's d) of genetic diversity were approximately half those of environment treatments, the greatest effect sizes were for interaction effects between genetic diversity and environment. Our results indicate that genetic diversity can have a large effect on ecological processes, but the direction of those effects is highly dependent upon environmental conditions, and not easily predicted from simple measures of traits. [ABSTRACT FROM AUTHOR]

Irruptive or boom-and-bust population dynamics, also known as 'outbreaks', are an important phenomenon that has been noted in biological invasions at least since Charles Elton's classic book was published in 1958. Community-level consequences of irruptive dynamics are poorly documented and invasive species provide excellent systems for their study. African Jewelfish (Rubricatochromis letourneuxi, "jewelfish") are omnivores that demonstrate opportunistic carnivory, first reported in Florida in the 1960s and in Everglades National Park (ENP) in 2000. Twelve years after invasion in ENP, jewelfish underwent a 25-fold increase in density in one year. By 2016, jewelfish represented 25–50% of fish biomass. Using a 43-year fish community dataset at two sites (1978–2021), and a 25-year dataset of fish and invertebrate communities from the same drainage (1996–2021), with additional spatial coverage, we quantified differences in fish and invertebrate communities during different phases of invasion. During jewelfish boom, abundant, native cyprinodontiform fishes decreased in density and drove changes in community structure as measured by similarity of relativized abundance. Density of two species declined by > 70%, while four declined by 50–62%. Following the jewelfish bust, some species recovered to pre-boom densities while others did not. Diversity of recovery times produced altered community structure that lagged for at least four years after the jewelfish population declined. Community structure is an index of ecological functions such as resilience, productivity, and species interaction webs; therefore, these results demonstrate that irruptive population dynamics can alter ecological functions of ecosystems mediated by community structure for years following that population's decline. [ABSTRACT FROM AUTHOR]

Tardigrades (Tardigrada) are a phylum of micrometazoans found in all biomes on Earth, but their ecology and habitat preferences remain vastly understudied. Boreal peatlands include a diversity of habitat types and high structural heterogeneity that represents an interesting system to study some of the poorly known habitat preferences of tardigrades. Here, we investigate for the first time tardigrade communities in peatland mosses and the latter's potential associations with key environmental variables. We collected 116 moss samples from 13 sites representing different peatland types and management histories. We found that tardigrades are common and diverse in boreal peatlands, as tardigrades were present in 72% of the collected samples and we identified 14 tardigrade genera. Tardigrade abundance seemed to increase alongside the increasing tree basal area and the density was higher in the microtopographic level further from the water table level, that is, hummocks (mean 117/moss gram) than in lawns/hollows (mean 84/moss gram). Furthermore, the highest tardigrade density was found in the moss taxa that are associated with forested peatland types (i.e., feather mosses) (321 mean/moss gram). Finally, we found interesting patterns regarding tardigrade functional diversity, as carnivorous tardigrades were found only in peatlands with tree basal area > 20 m2 and mostly in hummocks. Our study demonstrates that the habitat heterogeneity of peatlands (e.g., variation in moisture and vegetation cover) represents an interesting system to study tardigrade ecology and habitat preferences. However, since we found variation in tardigrade abundance and communities across peatland types and microhabitats within peatlands, our results highlight that such studies should be conducted with numerous replicate samples and a systematic study design that properly addresses the habitat heterogeneity between and within different peatland types. [ABSTRACT FROM AUTHOR]

The host microbiome can be considered an ecological community of microbes present inside a complex and dynamic host environment. The host is under selective pressure to ensure that its microbiome remains beneficial. The host can impose a range of ecological filters including the immune response that can influence the assembly and composition of the microbial community. How the host immune response interacts with the within-microbiome community dynamics to affect the assembly of the microbiome has been largely unexplored. We present here a mathematical framework to elucidate the role of host immune response and its interaction with the balance of ecological interactions types within the microbiome community. We find that highly mutualistic microbial communities characteristic of high community density are most susceptible to changes in immune control and become invasion prone as host immune control strength is increased. Whereas highly competitive communities remain relatively stable in resisting invasion to changing host immune control. Our model reveals that the host immune control can interact in unexpected ways with a microbial community depending on the prevalent ecological interactions types for that community. We stress the need to incorporate the role of host-control mechanisms to better understand microbiome community assembly and stability. [ABSTRACT FROM AUTHOR]

Tabanidae are considered a nuisance to humans, wild animals, and livestock due to their painful, annoying, and insistent biting. Tabanids transmit some pathogens and parasites biologically and mechanically. In humans, there are relatively few pathogens transmitted regularly. Still, tabanids serve as vectors of a number of disease agents of animals, including viruses, bacteria, protozoans, and nematodes. They are more abundant in tropical and humid regions, and their seasonal patterns are affected by habitat changes such as deforestation and fragmentation. Here, we analyze the tabanid fauna in Monte Negro, a central municipality of Rondônia, Brazil, comparing abundance, richness, and diversity in forest and pasture habitats. Traps were set for 5 days a month for 12 consecutive months. We also examined how abiotic factors (humidity, temperature, and rainfall) affected the abundance, diversity, and richness and the effectiveness of Malaise and Nzi traps as sample methods. The influence of climatic variables on the richness and abundance of the species was tested using generalized linear models, and we used non-parametric dimensional scaling (nMDS) for analysis of species composition and diversity in different traps and environments. We collect 1032 specimens of 25 species. The most abundant species were Tabanus antarcticus, Dichelacera tetradelta, Tabanus mucronatus, and Leucotabanus albovarius. Forest habitats had the highest number of tabanids, followed by pasture and the anthropized area, and there was no significant difference regarding the effectiveness of the Malaise and Nzi traps. The study provides new information on the distribution and ecology of tabanids in Brazil. [ABSTRACT FROM AUTHOR]

The increasing use of forest fuels poses risks to biodiversity. Lichens that grow on deadwood may be affected as fuel extraction removes their substrates. We surveyed deadwood and macrolichens on deadwood in two types of clearcuts: sites in which forest fuels, stumps and slash, had been extracted, and standard clearcut sites, i.e. control sites with no fuel extraction. Extraction sites had 52% lower deadwood volume (44.3 m³/ha vs. 21.4 m³/ha) and 36% less deadwood surface area. However, the negative impact of fuel extraction on macrolichen species richness was low: 21.4 and 16.9 species on average were found in control and extraction sites, respectively. We found a clear positive relationship between macrolichen species richness and the surface area of logs, which are usually not targeted by forest fuel extraction. Species composition varied more among extraction sites than control sites and differed between all the studied deadwood types. Species of Cladonia were associated with stumps, while species in the family Parmeliaceae were associated with logs. Slash was of negligible importance to macrolichens. Stumps may hold value, particularly if large-sized deadwood is otherwise not available. Thus, we conclude that the extraction of slash poses no threat to macrolichen diversity, whereas extensive extraction of stumps can cause losses in lichen diversity. The loss of coarse woody debris during forest fuel extraction has negative effects on lichen diversity and should be avoided. [ABSTRACT FROM AUTHOR]

Conservation is a major topic in primatology. In addition to focusing on individual species, the protection of interaction networks is key to conservation success, but difficulties in identifying these networks hinder research. We hope to inspire research in primate conservation through network analysis. We illustrate an approach for studying species networks using data for Tibetan macaques (Macaca thibetana) in three national nature reserves in Sichuan Province, China: Wolong, Tangjiahe, and Heizhugou. With data on species presence/absence from 185 cameras each continuously working for >12 months, we used the Phi coefficient rø to identify spatial association networks between species and the Lambda statistic LB to test the properties of the associations. We identified four networks across the reserves. Tibetan macaques were associated with four terrestrial/semi-arboreal bird and mammal species in Wolong and nine species in Tangjiahe, but only two species in Heizhugou. Macaques formed symmetrical associations, suggesting competition, unidirectional asymmetrical associations, suggesting commensalism, and bidirectional asymmetrical associations, suggesting mutualism. The macaque's community environment may be predation-free. Commensal and mutualistic interactions with Sichuan snub-nosed monkeys (Rhinopithecus roxellana) and three other species may enhance the ecological fitness of Tibetan macaques in Tangjiahe over that in Wolong and conservation investment for the macaque in Tangjiahe may benefit more species than that in Wolong. Asymmetrical associations may facilitate the ecological restoration of the degraded community in Heizhugou. Our approach may provide a sensitive method for ecological monitoring for conservation management, and facilitate primate community ecological research. [ABSTRACT FROM AUTHOR]

Mammal populations are declining due to habitat fragmentation and loss, but protected areas can maintain these populations at viable numbers and reduce their risk of extinction. This study assessed the mammal community composition, diversity profiles, seasonal variation, and habitat use in a protected area in the Brazilian Atlantic Forest. With an effort of 5,023 camera trap days, we registered 1,889 independent records of 20 species, with an additional 13 species recorded through direct observation. There was no difference in the seasonal diversity profiles of mammal communities. The diversity in submontane areas was consistently larger than in lowland ones, but the number of records was higher in lowland areas. The diversity profiles decrease when more weight is given to the common species. The reserve is the protected area with the third highest mammal richness in the state of Rio de Janeiro and harbors 11 threatened mammals. This study shows the importance of small protected areas for the conservation of mammalian diversity in a fragmented anthropogenic landscape. [ABSTRACT FROM AUTHOR]

Riparian taxa are subject to dynamic, intense, flood‐related stressors, and have evolved traits to persist in this environment. Climate change‐induced intensification of flood regimes pose a threat to these ecosystems, and little is understood about their resilience to this intensification. Following two consecutive major floods (the first flood record‐breaking) along the subtropical coast of eastern Australia in March 2022, we used methods based on persistence (resprouting, seedling recruitment), and floristic structure (height, DBH) and assemblage, to assess the resilience of an old growth riparian rainforest to severe flooding in the 12‐month post‐flooding window. Smallerwoody plants (stems <10 m tall, <30 cm DBH) were the most impacted and were significantly impacted by flooding. Native species richness and plant density (plants/m−2) significantly decreased between before and 3 months post‐flooding, after which they continued to significantly increase to surpass pre‐flood values. Overall, ~35% of taxa exhibited resprouting, ~28% of taxa exhibited seedling recruitment, and ~11% exhibited both resprouting and recruitment. An additional ~21% native taxa were introduced to the site via seedling recruitment, along with 65 invasive species. Model‐based multivariate analysis showed flooding significantly altered community floristics (p = 0.026) at 3 months. At 12 months post‐flooding the community was recovering, becoming more floristically similar to its pre‐flood composition. The riparian rainforest exhibited high resilience to intense flooding. Impact, persistence, and resilience varied amongplots, and the community took 12 months to move into recovery. We found that persistence, and floristic structure and composition weighted against impact were effective measures of ecosystem resilience. In the absence of further consecutive events, mature‐phase riparian rainforests are likely to be structurally and floristically resilient to climate change‐induced amplification of flood regimes. Further studies should build on this framework to include invasive weed species impacts, for a more accurate assessment of impacts. [ABSTRACT FROM AUTHOR]

Rising global temperatures are often identified as the key driver impacting ecosystems and the services they provide by affecting biodiversity structure and function. A disproportionate amount of our understanding of biodiversity and function is from short‐term experimental studies and static values of biodiversity indices, lacking the ability to monitor long‐term trends and capture community dynamics. Here, we analyse a biennial dataset spanning 32 years of macroinvertebrate benthic communities and their functional response to increasing temperatures. We monitored changes in species' thermal affinities to examine warming‐related shifts by selecting their mid‐point global temperature distribution range and linking them to species' traits. We employed a novel weighted metric using Biological Trait Analysis (BTA) to gain better insights into the ecological potential of each species by incorporating species abundance and body size and selecting a subset of traits that represent five ecosystem functions: bioturbation activity, sediment stability, nutrient recycling and higher and lower trophic production. Using biodiversity indices (richness, Simpson's diversity and vulnerability) and functional indices (richness, Rao's Q and redundancy), the community structure showed no significant change over time with a narrow range of variation. However, we show shifts in species composition with warming and increases in the abundance of individuals, which altered ecosystem functioning positively and/or non‐linearly. Yet, when higher taxonomic groupings than species were excluded from the analysis, there was only a weak increase in the measured change in community‐weighted average thermal affinities, suggesting changes in ecosystem functions over time occur independently of temperature increase‐related shifts in community composition. Other environmental factors driving species composition and abundance may be more important in these subtidal macrobenthic communities. This challenges the prevailing emphasis on temperature as the primary driver of ecological response to climate change and emphasises the necessity for a comprehensive understanding of the temporal dynamics of complex systems. [ABSTRACT FROM AUTHOR]

Plant-pollinator interactions are key for the reproduction of wild plants and for food security. However, the role nocturnal pollinators play in wild plant communities is not yet clear. Specifically, it has rarely been studied whether nocturnal pollinators are comparable to diurnal ones in the pollination services they deliver in plant communities. We tested whether nocturnal pollinators have the potential to provide high pollination services to the plants they visit by carrying high conspecific pollen loads. We studied pollen loads carried by nocturnal and diurnal pollinators captured over 24-hour cycles in co-flowering plant communities in Swiss ruderal meadows. Pollen load was less diverse at night, and the proportion of conspecific pollen carried by nocturnal pollinators was higher than that of diurnal ones. Because the majority of plant species visited at night were also visited during the day, floral resource availability could drive the observed patterns in pollen load and amount of conspecific pollen. Nevertheless, nocturnal pollinators do not only carry pollen but can remove and potentially deposit conspecific pollen to the plants they visit. Therefore, pollinators active at night might be an important pollination vector for more plant species than previously thought and should not be neglected in pollination studies. [ABSTRACT FROM AUTHOR]

This is the first survey of marine tardigrades from the British Virgin Islands, though two species were previously reported from St. Croix, U.S. Virgin Islands. In June 2016, we collected subtidal and intertidal sand samples from various locations throughout the British Virgin Islands. We found 602 tardigrades in 18 of 21 samples, and these included 12 taxa, one of which, Batillipes wyedeleinorum sp. nov., is new to science and described here. We compared abundance and species diversity in intertidal and subtidal samples and found significantly greater abundance in intertidal habitats but no significant difference in the number of observed species between the two habitats. We calculated Chao 1 species richness, which indicated higher estimated richness in intertidal habitats and 15 ± 3.7 species (x̅ ± SD) in both habitats combined. Non-metric Multidimensional Scaling revealed differences in species composition between the two habitats with some species showing clear preferences for one or the other. [ABSTRACT FROM AUTHOR]

Examining context-dependency of ecological impacts of alien plant invasions is critical to further understand the mechanisms driving impacts. We examined how different regional and local habitat contexts influence the abundance-impact associations of an invasive ground-creeper, Tradescantia fluminensis, in native forests across eastern New South Wales (NSW), Australia. Invader impacts were assessed using surveys of resident vegetation at 97 monitoring plots (5 m × 2 m) located at 14 sites, representing a gradient of T. fluminensis abundance. We modelled the association of T. fluminensis invasion with native species richness (number per plot) and foliage cover across two different habitat types (remnant vs replanted forests), two vegetation community types (wet sclerophyll vs river oak forests), and two regions (northern vs. southern NSW). We also modelled variation in native species responses amongst different functional growth forms. The negative associations of T. fluminensis and native species communities was more strongly explained by local site variables (i.e., habitat type, community type, plant growth form) than regional scales. Native richness reduced with invasion in river oak but not wet sclerophyll forest. Native richness also declined in remnant forest, although no effect of invasion was observed in replanted forest. Surprisingly, native species growth forms most like T. fluminensis (ground layer herbs, ferns) were more resistant to reductions in native richness compared to divergent forms (shrub, tree and woody vine recruits). This study highlights the need to explicitly consider local community and habitat context and functional representation of resident species when considering invader impacts and site-level management plans. [ABSTRACT FROM AUTHOR]

Specimen identification at the species level is a critical challenge for understanding community structure and conserving biodiversity. The use of mitochondrial DNA barcodes, in addition to morphology, has proven to be a useful tool for earthworm identification, but it has also raised difficulties. Thus, approaches to delineating molecular operational taxonomic units (MOTUs) from cytochrome c oxidase subunit 1 (COI) or 16S rDNA sequence data often reveal more mitochondrial lineages than morphospecies, raising the question of whether these MOTUs should be used as taxonomic entities in community structure studies. Here, we used a newly acquired dataset of 576 COI barcodes of earthworms from Metropolitan France that were clustered in 36 MOTUS, corresponding to 21 morphospecies. We also incorporated data gathered from the literature to investigate this question. In order to match our MOTUs with already-described mitochondrial lineages, we downloaded reference sequences from the GenBank and BOLD platforms. In light of the difficulties encountered in recovering these sequences, we recommend that any new mitochondrial lineage described in a study be named consistently with previous works. Next, we analyzed the biological, ecological, and molecular data available in the literature on the different mitochondrial lineages that matched our MOTUs in order to determine if there was a consensus for species delimitation. Although the study specimens mainly belong to the Lumbricidae, which is one of the most studied families of earthworms, the data are often missing to determine if the MOTUs correspond to different species. Pending revision of the taxonomy, MOTUs for which mitochondrial divergence has been confirmed by morphological differences should be considered distinct taxonomic entities in community structure studies. In the absence of morphological differences and pending more data, we propose to distinguish for these analyses, within sexually reproducing morphospecies, the MOTUs for which mitochondrial divergence has been confirmed by multilocus nuclear data, while in the case of reproduction by parthenogenesis, ecological differences between MOTUs are necessary to consider them as different taxonomic entities. [ABSTRACT FROM AUTHOR]

Background: Protists, single-celled eukaryotic organisms, are critical to food web ecology, contributing to primary productivity and connecting small bacteria and archaea to higher trophic levels. Lake Mendota is a large, eutrophic natural lake that is a Long-Term Ecological Research site and among the world's best-studied freshwater systems. Metagenomic samples have been collected and shotgun sequenced from Lake Mendota for the last 20 years. Here, we analyze this comprehensive time series to infer changes to the structure and function of the protistan community and to hypothesize about their interactions with bacteria. Results: Based on small subunit rRNA genes extracted from the metagenomes and metagenome-assembled genomes of microeukaryotes, we identify shifts in the eukaryotic phytoplankton community over time, which we predict to be a consequence of reduced zooplankton grazing pressures after the invasion of a invasive predator (the spiny water flea) to the lake. The metagenomic data also reveal the presence of the spiny water flea and the zebra mussel, a second invasive species to Lake Mendota, prior to their visual identification during routine monitoring. Furthermore, we use species co-occurrence and co-abundance analysis to connect the protistan community with bacterial taxa. Correlation analysis suggests that protists and bacteria may interact or respond similarly to environmental conditions. Cryptophytes declined in the second decade of the timeseries, while many alveolate groups (e.g., ciliates and dinoflagellates) and diatoms increased in abundance, changes that have implications for food web efficiency in Lake Mendota. Conclusions: We demonstrate that metagenomic sequence-based community analysis can complement existing efforts to monitor protists in Lake Mendota based on microscopy-based count surveys. We observed patterns of seasonal abundance in microeukaryotes in Lake Mendota that corroborated expectations from other systems, including high abundance of cryptophytes in winter and diatoms in fall and spring, but with much higher resolution than previous surveys. Our study identified long-term changes in the abundance of eukaryotic microbes and provided context for the known establishment of an invasive species that catalyzes a trophic cascade involving protists. Our findings are important for decoding potential long-term consequences of human interventions, including invasive species introduction. BaNPxYigHXA7H5uqkH8sry Video Abstract [ABSTRACT FROM AUTHOR]

Aim Location Taxon Methods Results Main Conclusions Mountains are often used to study how environmental factors influence biodiversity. However, we have limited understanding of the processes causing biodiversity variation in mountains and whether such processes vary across trophic levels and spatial scales. The aim of this study was to evaluate (i) whether community assembly processes varied along elevational gradients, (ii) whether there were differences in such variation between primary producers (vascular plants) and secondary consumers (spiders) and (iii) whether there were scale dependencies in any elevational variation in community assembly.Fennoscandia, Northern Sweden.Vascular plants, spiders.We used phenotypic and phylogenetic dispersion to quantify how elevation influenced community assembly of vascular plants and spiders and whether there were any scale dependencies in such influences. Our original data of plant and spider communities came from our own field surveys, phenotypic dispersion was calculated based on matrices of ecological traits, and phylogenetic dispersion was calculated from phylogenetic trees for each organism group. Trait matrices were based on a combination of literature values and our own measurements. The phylogeny for vascular plants was based on a published plant super‐tree, whereas the phylogeny for spiders was created by ourselves based on the DNA sequences at the mitochondrial cytochrome c oxidase subunit 1 (COI).Plants were environmentally filtered throughout all elevations and scales, but the importance of convergent evolution increased with elevation. For spiders, the importance of environmental filtering as well as niche conservatism increased with elevation. For both groups, communities at smaller scales were more influenced by biotic regulation and niche conservatism than at larger scales.Our study highlights both taxonomic differences and scale dependencies in how elevation influences community assembly. We argue that these results can have broad ramifications for our understanding of how spatial variation in biodiversity is generated and maintained. This may have particular relevance for our ability to predict the ecological consequences of climate change. Our results further highlight that high elevation specialists may suffer increased risks of climate driven extinctions due to a combination of increased competition and increased fragmentation of suitable habitats. Particularly for spiders, which had high elevation specialists clustered along specific lineages, such extinctions could lead to significant loss of phylogenetic variation. [ABSTRACT FROM AUTHOR]

Nature‐based solutions (NbS) involve interventions that modify ecosystems to enhance multiple ecosystem services (ES). Yet, despite our increasing knowledge of the key role that functional traits play in determining ES, certain types of NbS often do not consider a functional trait perspective. A reason for this lack of translation may be the range of NbS approaches and levels of knowledge of trait–ES relationships. Functional traits may be most useful as targets for NbS design when knowledge on trait–ES mapping is established and the NbS involves a medium or high level of management intervention. A richer understanding of causality in trait–ES and trait–resilience linkages, and context dependency in those linkages, is needed to broaden the application of functional traits in NbS. An improved understanding of trait linkages with cultural ES and how traits interact with stakeholder values to shape NbS uptake would also improve application. Synthesis: A greater consideration of functional traits will increase the efficacy of NbS projects, and could be accelerated by tackling gaps in knowledge about functional traits. Here, we envision a research agenda that both advances NbS design and leverages the varied objectives of NbS to robustly test our knowledge about functional traits. [ABSTRACT FROM AUTHOR]

Population and community ecology as a science are about 100 years old, and we discuss here our opinion of what approaches have progressed well and which point to possible future directions. The three major threads within population and community ecology are theoretical ecology, statistical tests and models, and experimental ecology. We suggest that our major objective is to understand what factors determine the distribution and abundance of organisms within populations and communities, and we evaluate these threads against this major objective. Theoretical ecology is elegant and compelling and has laid the groundwork for achieving our overall objectives with useful simple models. Statistics and statistical models have contributed informative methods to analyze quantitatively our understanding of distribution and abundance for future research. Population ecology is difficult to carry out in the field, even though we may have all the statistical methods and models needed to achieve results. Community ecology is growing rapidly with much description but less understanding of why changes occur. Biodiversity science cuts across all these subdivisions but rarely digs into the necessary population and community science that might solve conservation problems. Climate change affects all aspects of ecology but to assume that everything in population and community ecology is driven by climate change is oversimplified. We make recommendations on how to advance the field with advice for present and future generations of population and community ecologists. [ABSTRACT FROM AUTHOR]

Many plants have evolved nutrient rewards to attract pollinators to flowers, but most research has focused on the sugar content of floral nectar resources. Concentrations of sodium in floral nectar (a micronutrient in low concentrations in nectar) can vary substantially both among and within co‐occurring species. It is hypothesized that sodium concentrations in floral nectar might play an important and underappreciated role in plant–pollinator interactions, especially because many animals, including pollinators, are sodium limited in nature. Yet, the consequences of variation in sodium concentrations in floral nectar remain largely unexplored. Here, we investigate whether enriching floral nectar with sodium influences the composition, diversity, and frequency of plant–pollinator interactions. We experimentally enriched sodium concentrations in four plant species in a subalpine meadow in Colorado, USA. We found that flowers with sodium‐enriched nectar received more visits from a greater diversity of pollinators throughout the season. Different pollinator species foraged more frequently on flowers enriched with sodium and showed evidence of other changes to foraging behavior, including greater dietary evenness. These findings are consistent with the "salty nectar hypothesis," providing evidence for the importance of sodium limitation in pollinators and suggesting that even small nectar constituents can shape plant–pollinator interactions. [ABSTRACT FROM AUTHOR]

Aim: Human‐driven landscape processes such as habitat loss and fragmentation act on biodiversity, but their effects are mediated by the spatial scale at which they are observed. We aim to analyse the scale‐of‐effects (direction and spatial extent) of landscape‐scale processes that best explain species richness and abundance across epiphyte communities. Location: Neotropics, Northern Andes, Colombia, Eastern cordillera. Taxon: Vascular epiphytes, Orchidaceae. Methods: We used field data to unravel the scale‐of‐effect of three landscape processes—habitat loss (forest cover), fragmentation (number of patches) and edge effects (edge density)—on epiphyte biodiversity. Vascular epiphytes were sampled in the understorey across 141 plots within 23 Andean forests in the eastern Colombian cordillera We focused on the community‐level responses (species richness and total abundance) of the hyperdiverse vascular epiphyte communities using generalized linear mixed models to quantify the direction and the spatial extent of the scale‐of‐effects. Results: Habitat loss and edge effects act at fine spatial extents (scale‐of‐effects = 200 m), predicting low species richness and abundance across groups. Likewise, fragmentation negatively impacts communities, but operates at larger spatial extents (scale‐of‐effects = 2000–2400 m radius). The detection of these effects is contingent upon the spatial extent and specific landscape processes involved. Models of habitat loss within a spatial extent of 800–1500 m (large confidence intervals), fragmentation below 300 m, and edge effects above 800 m show weak statistical support (marginal r2 = 0.02–0.1). Thus, the impacts of these landscape processes may be overlooked if studied at inadequate spatial extents. Main Conclusions: We showed that habitat loss, fragmentation and edge effects all play a negative role on understorey epiphytic communities, but their detectability is scale dependant. The scale‐of‐effects can assist landscape designs that are beneficial for epiphytic communities, by preserving forest cover, and reducing fragmentation and exposure to edge effects at small scales (200–300 m). Conversely, landscape‐scale actions directed at reducing habitat loss and fragmentation function at larger spatial extents (>2000 m). Selecting a priori or inadequate spatial extents of analysis can obscure the detectability of landscape processes. [ABSTRACT FROM AUTHOR]

Camera‐trap surveys are increasingly used to assess species interactions, with a growing focus on proximate co‐occurrence, the conditional probability of one species occurring after another within a given time window. However, existing time‐to‐first‐event models, commonly employed for this purpose, suffer from multiple limitations. For instance, they cannot fully quantify the interaction strength, that is how strongly one species affects the occurrence probability of another, nor the duration of this effect, nor identify the directionality of the interaction.We propose reframing the question in terms of recurrent event analysis, which enables the use of a rich set of techniques to provide more information about the data‐generating process. In particular, we use the piece‐wise exponential additive mixed model (PAMM) to take into account all available information (including recurrent occurrences of species) and to estimate the non‐linear temporal dynamics of the visitation rate of a species after the occurrence of another. As the estimation is performed within the framework of generalized additive models, it offers a rich, robust and established inferential toolbox.We evaluated PAMM's performance in estimating species interactions through a simulation study involving two species under various scenarios of attraction or repulsion, with and without imperfect detection. Additionally, we compared the PAMM to six time‐to‐first‐event methods commonly used in camera‐trap studies and illustrated its application with real data.PAMMs outperformed the other methods in terms of statistical power, output interpretability and ability to disentangle interactions. The robust performance of PAMMs underscores their potential as a valuable tool for studying species interactions based on camera‐trap data. To facilitate its adoption, we present the new package ctrecurrent and provide a reproducible workflow from data preparation to model fitting. [ABSTRACT FROM AUTHOR]

To understand the relationship between environmental factors and black fly (Simuliidae) species’ distributions, we sampled immature individuals in Pedra Branca State Park, Rio de Janeiro, Brazil, during the dry season in June 2018. We then correlated environmental variable values with black fly larvae abundances via redundancy analyses. The abundances of Simulium pertinax Kollar 1832, Simulium subpallidum Lutz 1910, Simulium (Thyrsopelma) spp., Simulium (Psaroniocompsa) spp., and Simulium (Inaequalium) spp. were negatively correlated with light and temperature, while Simulium (Hemicne tha) spp.’s abundance correlated positively with these variables. The abundances of Simulium pertinax Kollar 1832, Simulium (Hemicnetha) spp., and Simulium (Thyrsopelma) spp. were positively associated with altitude, while the abundances of the other species revealed negative correlations with this factor. Species richness was determined using pupae in a linear regression with the Ephemeroptera, Plecoptera Trichoptera (EPT) index. This analysis showed that the most deteriorated sites have a higher species richness than more conserved sites within Pedra Branca State Park. Our results suggest that simuliid species richness reflects habitat integrity, thus becoming a reliable indicator of habitat conservatio status.

Plant-pollinator interactions are key for the reproduction of wild plants and for food security. However, the role nocturnal pollinators play in wild plant communities is not yet clear. Specifically, it has rarely been studied whether nocturnal pollinators are comparable to diurnal ones in the pollination services they deliver in plant communities. We tested whether nocturnal pollinators have the potential to provide high pollination services to the plants they visit by carrying high conspecific pollen loads. We studied pollen loads carried by nocturnal and diurnal pollinators captured over 24-hour cycles in co-flowering plant communities in Swiss ruderal meadows. Pollen load was less diverse at night, and the proportion of conspecific pollen carried by nocturnal pollinators was higher than that of diurnal ones. Because the majority of plant species visited at night were also visited during the day, floral resource availability could drive the observed patterns in pollen load and amount of conspecific pollen. Nevertheless, nocturnal pollinators do not only carry pollen but can remove and potentially deposit conspecific pollen to the plants they visit. Therefore, pollinators active at night might be an important pollination vector for more plant species than previously thought and should not be neglected in pollination studies.

Abstract Background Protists, single-celled eukaryotic organisms, are critical to food web ecology, contributing to primary productivity and connecting small bacteria and archaea to higher trophic levels. Lake Mendota is a large, eutrophic natural lake that is a Long-Term Ecological Research site and among the world’s best-studied freshwater systems. Metagenomic samples have been collected and shotgun sequenced from Lake Mendota for the last 20 years. Here, we analyze this comprehensive time series to infer changes to the structure and function of the protistan community and to hypothesize about their interactions with bacteria. Results Based on small subunit rRNA genes extracted from the metagenomes and metagenome-assembled genomes of microeukaryotes, we identify shifts in the eukaryotic phytoplankton community over time, which we predict to be a consequence of reduced zooplankton grazing pressures after the invasion of a invasive predator (the spiny water flea) to the lake. The metagenomic data also reveal the presence of the spiny water flea and the zebra mussel, a second invasive species to Lake Mendota, prior to their visual identification during routine monitoring. Furthermore, we use species co-occurrence and co-abundance analysis to connect the protistan community with bacterial taxa. Correlation analysis suggests that protists and bacteria may interact or respond similarly to environmental conditions. Cryptophytes declined in the second decade of the timeseries, while many alveolate groups (e.g., ciliates and dinoflagellates) and diatoms increased in abundance, changes that have implications for food web efficiency in Lake Mendota. Conclusions We demonstrate that metagenomic sequence-based community analysis can complement existing efforts to monitor protists in Lake Mendota based on microscopy-based count surveys. We observed patterns of seasonal abundance in microeukaryotes in Lake Mendota that corroborated expectations from other systems, including high abundance of cryptophytes in winter and diatoms in fall and spring, but with much higher resolution than previous surveys. Our study identified long-term changes in the abundance of eukaryotic microbes and provided context for the known establishment of an invasive species that catalyzes a trophic cascade involving protists. Our findings are important for decoding potential long-term consequences of human interventions, including invasive species introduction. Video Abstract

Abstract Camera‐trap surveys are increasingly used to assess species interactions, with a growing focus on proximate co‐occurrence, the conditional probability of one species occurring after another within a given time window. However, existing time‐to‐first‐event models, commonly employed for this purpose, suffer from multiple limitations. For instance, they cannot fully quantify the interaction strength, that is how strongly one species affects the occurrence probability of another, nor the duration of this effect, nor identify the directionality of the interaction. We propose reframing the question in terms of recurrent event analysis, which enables the use of a rich set of techniques to provide more information about the data‐generating process. In particular, we use the piece‐wise exponential additive mixed model (PAMM) to take into account all available information (including recurrent occurrences of species) and to estimate the non‐linear temporal dynamics of the visitation rate of a species after the occurrence of another. As the estimation is performed within the framework of generalized additive models, it offers a rich, robust and established inferential toolbox. We evaluated PAMM's performance in estimating species interactions through a simulation study involving two species under various scenarios of attraction or repulsion, with and without imperfect detection. Additionally, we compared the PAMM to six time‐to‐first‐event methods commonly used in camera‐trap studies and illustrated its application with real data. PAMMs outperformed the other methods in terms of statistical power, output interpretability and ability to disentangle interactions. The robust performance of PAMMs underscores their potential as a valuable tool for studying species interactions based on camera‐trap data. To facilitate its adoption, we present the new package ctrecurrent and provide a reproducible workflow from data preparation to model fitting.

Scavengers benefit from carrion and simultaneously provide essential ecosystem services. To assess benefits and risks that carrion might bring, it is crucial to understand ecosystem-specific scavenger communities. Carrion research has mostly focussed on ungulate carcasses and has rarely explored the effects of carnivore carcasses, which can be critical to understanding disease transmission pathways. Therefore, using red fox, roe deer and red deer carcasses, we investigated factors that affect facultative vertebrate scavenger assemblages visiting carnivore and herbivore carcasses in a temperate forest ecosystem. Due to potentially increased disease transmission risk associated with carnivore carrion, we predicted that carnivore carcasses would be visited less and have a reduced visiting species composition compared to herbivore carcasses. Further, we expected red foxes to exhibit less consumption behavior of conspecific carcasses. We placed 22 red fox and 22 herbivore carcasses in a temperate montane protected area in Central Europe, the Bavarian Forest National Park, and analyzed the visits of all species and the consumption behavior of red fox at carcasses to understand whether these depended on carcass type. We found no significant effects of carcass type on visitation rates, visiting species composition, or red fox behavior. Cannibalism of foxes was common and, when controlling for confounding factors, e.g., elevation, temperature, and scavenging seasonality, the predicted consumption rate of red fox at conspecifics was higher than at herbivore carrion. Foxes appeared to consume conspecifics earlier than herbivore carrion, but the difference was not significant. At the very least, our results show that carnivore carcasses and fox behavior, including cannibalism, could provide a pathway for disease transmission. We thereby provide a first impression of the patterns of vertebrate scavenger assemblages at different carcass types in a temperate ecosystem and show that red fox behavior might precipitate a disease transmission pathway.

Abstract The erosion of the colonic mucus layer by a dietary fiber-deprived gut microbiota results in heightened susceptibility to an attaching and effacing pathogen, Citrobacter rodentium. Nevertheless, the questions of whether and how specific mucolytic bacteria aid in the increased pathogen susceptibility remain unexplored. Here, we leverage a functionally characterized, 14-member synthetic human microbiota in gnotobiotic mice to deduce which bacteria and functions are responsible for the pathogen susceptibility. Using strain dropouts of mucolytic bacteria from the community, we show that Akkermansia muciniphila renders the host more vulnerable to the mucosal pathogen during fiber deprivation. However, the presence of A. muciniphila reduces pathogen load on a fiber-sufficient diet, highlighting the context-dependent beneficial effects of this mucin specialist. The enhanced pathogen susceptibility is not owing to altered host immune or pathogen responses, but is driven by a combination of increased mucus penetrability and altered activities of A. muciniphila and other community members. Our study provides novel insights into the mechanisms of how discrete functional responses of the same mucolytic bacterium either resist or enhance enteric pathogen susceptibility.

Abstract Coevolution describes evolutionary change in which two or more interacting species reciprocally drive each other’s evolution, potentially resulting in trait diversification and ecological speciation. Much progress has been made in analysis of its dynamics and consequences, but relatively little is understood about how coevolution works in multispecies interactions, i.e., those with diverse suites of species on one or both sides of an interaction. Interactions among plant hosts and their mutualistic ectomycorrhizal fungi (ECM) may provide an ecologically unique arena to examine the nature of selection in multispecies interactions. Using native genotypes of Monterey pine (Pinus radiata), we performed a common garden experiment at a field site that contains native stands to investigate selection from ECM fungi on pine traits. We planted seedlings from all five native populations, as well as inter-population crosses to represent intermediate phenotypes/genotypes, and measured seedling traits and ECM fungal traits to evaluate the potential for evolution in the symbiosis. We then combined field estimates of selection gradients with estimates of heritability and genetic variance–covariance matrices for multiple traits of the mutualism to determine which fungal traits drive plant fitness variation. We found evidence that certain fungal operational taxonomic units, families and species-level morphological traits by which ECM fungi acquire and transport nutrients exert selection on plant traits related to growth and allocation patterns. This work represents the first field-based, community-level study measuring multispecific coevolutionary selection in nutritional symbioses.

Abstract Purpose The rising burden of mosquito-borne diseases in Europe extends beyond urban areas, encompassing rural and semi-urban regions near managed and natural wetlands evidenced by recent outbreaks of Usutu and West Nile viruses. While wetland management policies focus on biodiversity and ecosystem services, few studies explore the impact on mosquito vectors. Methods Our research addresses this gap, examining juvenile mosquito and aquatic predator communities in 67 ditch sites within a South England coastal marsh subjected to different wetland management tiers. Using joint distribution models, we analyse how mosquito communities respond to abiotic and biotic factors influenced by wetland management. Results Of the 12 mosquito species identified, Culiseta annulata (Usutu virus vector) and Culex pipiens (Usutu and West Nile virus vector) constitute 47% of 6825 larval mosquitoes. Abundant predators include Coleoptera (water beetles) adults, Corixidae (water boatmen) and Zygoptera (Damselfy) larvae. Models reveal that tier 3 management sites (higher winter water levels, lower agricultural intensity) associated with shade and less floating vegetation are preferred by specific mosquito species. All mosquito species except Anopheles maculipennis s.l., are negatively impacted by potential predators. Culiseta annulata shows positive associations with shaded and turbid water, contrary to preferences of Corixidae predators. Conclusions Tier 3 areas managed for biodiversity, characterised by higher seasonal water levels and reduced livestock grazing intensity, provide favourable habitats for key mosquito species that are known vectors of arboviruses, such as Usutu and West Nile. Our findings emphasise the impact of biodiversity-focused wetland management, altering mosquito breeding site vegetation to enhance vector suitability. Further exploration of these trade-offs is crucial for comprehending the broader implications of wetland management.

Abstract Dominant vegetation in many ecosystems is an integral component of structure and habitat. In many drylands, native shrubs function as foundation species that benefit other plants and animals. However, invasive exotic plant species can comprise a significant proportion of the vegetation. In Central California drylands, the facilitative shrub Ephedra californica and the invasive Bromus rubens are widely dispersed and common. Using comprehensive survey data structured by shrub and open gaps for the region, we compared network structure with and without this native shrub canopy and with and without the invasive brome. The presence of the invasive brome profoundly shifted the network measure of centrality in the microsites structured by a shrub canopy (centrality scores increased from 4.3 under shrubs without brome to 6.3, i.e. a relative increase of 42%). This strongly suggests that plant species such as brome can undermine the positive and stabilizing effects of native foundation plant species provided by shrubs in drylands by changing the frequency that the remaining species connect to one another. The net proportion of positive and negative associations was consistent across all microsites (approximately 50% with a total of 14% non-random co-occurrences on average) suggesting that these plant-plant networks are rewired but not more negative. Maintaining resilience in biodiversity thus needs to capitalize on protecting native shrubs whilst also controlling invasive grass species particularly when associated with shrubs.

Public health concerns about recent viral epidemics have motivated researchers to seek novel ways to understand pathogen infection in native, wildlife hosts. With its deep history of tools and perspectives for understanding the abundance and distribution of organisms, ecology can shed new light on viral infection dynamics. However, datasets allowing deep explorations of viral communities from an ecological perspective are lacking. We sampled 1086 bats from two, adjacent Puerto Rican caves and tested them for infection by herpesviruses, resulting in 3131 short, viral sequences. Using percent identity of nucleotides and a machine learning algorithm (affinity propagation), we categorized herpesviruses into 43 operational taxonomic units (OTUs) to be used in place of species in subsequent ecological analyses. Herpesvirus metacommunities demonstrated long‐tailed rank frequency distributions at all analyzed levels of host organization (i.e., individual, population, and community). Although 13 herpesvirus OTUs were detected in more than one host species, OTUs generally exhibited host specificity by infecting a single core host species at a significantly higher prevalence than in all satellite species combined. We describe the natural history of herpesvirus metacommunities in Puerto Rican bats and suggest that viruses follow the general law that communities comprise few common and many rare species. To guide future efforts in the field of viral ecology, hypotheses are presented regarding mechanisms that contribute to these patterns. [ABSTRACT FROM AUTHOR]

Beta diversity patterns along environmental gradients and underlying mechanisms constitute key research inquiries in biogeography. However, ecological processes often also influence the functional traits of biological communities, making the assessment of functional β‐diversity crucial. Ground beetles (Coleoptera: Carabidae) are one of the most species‐rich groups in the insect community, displaying strong habitat specificity and morphological differences. In this study, we explored the patterns of taxonomic and functional beta diversity in ground beetle communities along the altitudinal gradient of warm‐temperature forests. By partitioning beta diversity into turnover and nestedness components, we evaluated their relationship with spatial distance. Our findings indicate a decline in species and functional trait similarity with increasing elevation and geographic distance. Further analysis attributed both types of beta diversity in carabids to a combination of dispersal limitation and environmental filtering, with elevation and geographic distance emerging as significant factors. Interestingly, forest‐type variations were found to have no impact on the beta diversity of these communities. Our study reveals the impact of environmental filtering and dispersal limitation on both taxonomic and functional beta‐diversity, shedding light on carabid community assembly in localized warm‐temperature forest areas in eastern China. [ABSTRACT FROM AUTHOR]

In depressional freshwater wetlands, habitat size, hydrology, and fish predation are considered key controls on invertebrate assemblages. However, the relative importance of each of these factors is difficult to isolate because the factors are frequently correlated. We assessed controls exerted by habitat size, hydrology, and fish occurrence in a set of 10 Carolina bay wetlands where these factors were largely independent. Invertebrate assemblages were sampled seasonally for six years. Using Joint Species Distribution Modeling of presence/absence and relative abundance data, < 6% of the variance in overall invertebrate assemblages was explained by the combined effects of size, hydrology, and fish occurrence: hydrology explained the most. However, when assessing responses of individual taxa, 32% were responsive, again primarily to variation in hydrology. Habitat size was minimally important. Fish occurrence affected only a handful of taxa, but some of those were key ecologically (abundant consumers). Most taxa responded to only one of the three environmental factors; effect sizes for responses ranged from 2 to 15.6% of total variance explained. Overall, the influences of habitat size, hydrology, and fish occurrence were less important to invertebrates in Carolina bay wetlands than we had presumed, given the prominence of these controls in the wetland invertebrate literature. [ABSTRACT FROM AUTHOR]

The erosion of the colonic mucus layer by a dietary fiber-deprived gut microbiota results in heightened susceptibility to an attaching and effacing pathogen, Citrobacter rodentium. Nevertheless, the questions of whether and how specific mucolytic bacteria aid in the increased pathogen susceptibility remain unexplored. Here, we leverage a functionally characterized, 14-member synthetic human microbiota in gnotobiotic mice to deduce which bacteria and functions are responsible for the pathogen susceptibility. Using strain dropouts of mucolytic bacteria from the community, we show that Akkermansia muciniphila renders the host more vulnerable to the mucosal pathogen during fiber deprivation. However, the presence of A. muciniphila reduces pathogen load on a fiber-sufficient diet, highlighting the context-dependent beneficial effects of this mucin specialist. The enhanced pathogen susceptibility is not owing to altered host immune or pathogen responses, but is driven by a combination of increased mucus penetrability and altered activities of A. muciniphila and other community members. Our study provides novel insights into the mechanisms of how discrete functional responses of the same mucolytic bacterium either resist or enhance enteric pathogen susceptibility. Synopsis: Susceptibility to a mucosal pathogen is both microbiome- and diet-dependent, with mucin specialist Akkermansia muciniphila increasing susceptibility on a fiber-free diet, whereas a fiber-rich diet allows the same commensal to confer resistance. Variations of a 14-member synthetic human gut microbiota show the key role of dietary fiber in determining the severity of Citrobacter rodentium infection through specific members of the microbiome. Combined action of increased mucus barrier permeability and altered community networks underlie the increased pathogen susceptibility in the Akkermansia muciniphila-containing communities fed a fiber-free diet. Exclusion of Akkermansia muciniphila from the synthetic microbiota or consumption of a fiber-rich diet is sufficient to prevent severe infection. Dietary context is key, with the presence of Akkermansia muciniphila protecting against severe infection under fiber-rich conditions. Susceptibility to a mucosal pathogen is both microbiome- and diet-dependent, with mucin specialist Akkermansia muciniphila increasing susceptibility on a fiber-free diet, whereas a fiber-rich diet allows the same commensal to confer resistance. [ABSTRACT FROM AUTHOR]

Understanding the mechanisms that maintain species coexistence and determine patterns of community assembly are fundamental goals of ecology. Quantifying the relationship between species traits and stress gradients is a necessary step to disentangle assembly processes and to be able to predict the outcome of environmental change. We examined the hypothesis that desert ant communities are assembled by niche-based processes i.e., environmental filtering and limiting similarity. First, we used population-level morphological trait measurements to study the functional structure of ant communities along a dryland environmental stress gradient. Second, we developed species distribution models for each species to quantify large-scale climatic niche overlap between species. Body, femur, antennal scape, and head lengths were correlated with environmental gradients. Regionally, the ant community was significantly and functionally overdispersed in terms of morphological traits which suggests the importance of competition to ant community structure. Ant community assembly was also strongly influenced by environmental factors as the degree of functional trait divergence, but not phylogenetic divergence, decreased with increasing environmental stress. Thus, environmental stress likely mediates limiting similarity in these desert ecosystems. Species with lower climatic niche overlap were more dissimilar in morphological traits. This suggests that environmental filtering on ant functional traits is important at the scale of species distributions in addition to regional scales. This study shows that environmental and biotic filtering (i.e., niche-based assembly mechanisms) are jointly and non-independently structuring the ant community. [ABSTRACT FROM AUTHOR]

[Display omitted] • Host contact zone dynamics can be influenced by parasites. • Luscinia nightingales have significantly different haemosporidian prevalence. • Differential prevalence did not change in sympatry versus allopatry. • Community structure was significantly different between hosts, even in sympatry. • Parasites are unlikely to drive contact zone dynamics in nightingales. Parasites are a key driving force behind many ecological and evolutionary processes. Prevalence and diversity of parasites, as well as their effects on hosts, are not uniform across host species. As such, the potential parasite spillover between species can significantly influence outcomes of interspecific interactions. We screened two species of Luscinia nightingales for haemosporidian blood parasites (Plasmodium, Leucocytozoon and Haemoproteus) along an approximately 3000 km transect in Europe, incorporating areas of host distant allopatry, close allopatry and sympatry. We found significant differences in infection rates between the two host species, with common nightingales having much lower parasite prevalence than thrush nightingales (36.7% versus 83.8%). This disparity was mostly driven by Haemoproteus prevalence, which was significantly higher in thrush nightingales while common nightingales had a small, but significantly higher, Plasmodium prevalence. Furthermore, we found no effect of proximity to the contact zone on infection rate in either host species. Despite having lower infection prevalence, common nightingales were infected with a significantly higher diversity of parasite lineages than thrush nightingales, and lineage assemblages differed considerably between the two species, even in sympatry. This pattern was mostly driven by the large diversity of comparatively rare lineages, while the most abundant lineages were shared between the two host species. This suggests that, despite the close evolutionary relationships between the two nightingales, there are significant differences in parasite prevalence and diversity, regardless of the distance from the contact zone. This suggests that spillover of haemosporidian blood parasites is unlikely to contribute towards interspecific interactions in this system. [ABSTRACT FROM AUTHOR]

Multifunctional landscapes that support economic activities and conservation of biological diversity (e.g., cattle ranches with native forest) are becoming increasingly important because small remnants of native forest may comprise the only habitat left for some wildlife species. Understanding the co‐occurrence between wildlife and disturbance factors, such as poaching activity and domesticated ungulates, is key to successful management of multifunctional landscapes. Tools to measure co‐occurrence between wildlife and disturbance factors include camera traps and autonomous acoustic recording units. We paired 52 camera‐trap stations with acoustic recorders to investigate the association between 2 measures of disturbance (poaching and cattle) and wild ungulates present in multifunctional landscapes of the Colombian Orinoquía. We used joint species distribution models to investigate species–habitat associations and species–disturbance correlations. One model was fitted using camera‐trap data to detect wild ungulates and disturbance factors, and a second model was fitted after replacing camera‐trap detections of disturbance factors with their corresponding acoustic detections. The direction, significance, and precision of the effect of covariates depended on the sampling method used for disturbance factors. Acoustic monitoring typically resulted in more precise estimates of the effects of covariates and of species–disturbance correlations. Association patterns between wildlife and disturbance factors were found only when disturbance was detected by acoustic recorders. Camera traps allowed us to detect nonvocalizing species, whereas audio recording devices increased detection of disturbance factors leading to more precise estimates of co‐occurrence patterns. The collared peccary (Pecari tajacu), lowland tapir (Tapirus terrestris), and white‐tailed deer (Odocoileus virginianus) co‐occurred with disturbance factors and are conservation priorities due to the greater risk of poaching or disease transmission from cattle. [ABSTRACT FROM AUTHOR]

Scavengers benefit from carrion and simultaneously provide essential ecosystem services. To assess benefits and risks that carrion might bring, it is crucial to understand ecosystem-specific scavenger communities. Carrion research has mostly focussed on ungulate carcasses and has rarely explored the effects of carnivore carcasses, which can be critical to understanding disease transmission pathways. Therefore, using red fox, roe deer and red deer carcasses, we investigated factors that affect facultative vertebrate scavenger assemblages visiting carnivore and herbivore carcasses in a temperate forest ecosystem. Due to potentially increased disease transmission risk associated with carnivore carrion, we predicted that carnivore carcasses would be visited less and have a reduced visiting species composition compared to herbivore carcasses. Further, we expected red foxes to exhibit less consumption behavior of conspecific carcasses. We placed 22 red fox and 22 herbivore carcasses in a temperate montane protected area in Central Europe, the Bavarian Forest National Park, and analyzed the visits of all species and the consumption behavior of red fox at carcasses to understand whether these depended on carcass type. We found no significant effects of carcass type on visitation rates, visiting species composition, or red fox behavior. Cannibalism of foxes was common and, when controlling for confounding factors, e.g., elevation, temperature, and scavenging seasonality, the predicted consumption rate of red fox at conspecifics was higher than at herbivore carrion. Foxes appeared to consume conspecifics earlier than herbivore carrion, but the difference was not significant. At the very least, our results show that carnivore carcasses and fox behavior, including cannibalism, could provide a pathway for disease transmission. We thereby provide a first impression of the patterns of vertebrate scavenger assemblages at different carcass types in a temperate ecosystem and show that red fox behavior might precipitate a disease transmission pathway. [ABSTRACT FROM AUTHOR]

European grasslands are among the most species-rich ecosystems on small spatial scales. However, human-induced activities like land use and climate change pose significant threats to this diversity. To explore how climate and land cover change will affect biodiversity and community composition in grassland ecosystems, we conducted joint species distribution models (SDMs) on the extensive vegetation-plot database sPlotOpen to project distributions of 1178 grassland species across Europe under current conditions and three future scenarios. We further compared model accuracy and computational efficiency between joint SDMs (JSDMs) and stacked SDMs, especially for rare species. Our results show that: (i) grassland communities in the mountain ranges are expected to suffer high rates of species loss, while those in western, northern and eastern Europe will experience substantial turnover; (ii) scaling anomalies were observed in the predicted species richness, reflecting regional differences in the dominant drivers of assembly processes; (iii) JSDMs did not outperform stacked SDMs in predictive power but demonstrated superior efficiency in model fitting and predicting; and (iv) incorporating co-occurrence datasets improved the model performance in predicting the distribution of rare species. This article is part of the theme issue 'Ecological novelty and planetary stewardship: biodiversity dynamics in a transforming biosphere'. [ABSTRACT FROM AUTHOR]