Search

Community dynamics within microbial mat assemblages are complex, likely involving intricate metabolic linkages. Interactions between microbes shape these communities, particularly in extreme habitats such as those found in the Middle Island Sinkhole (MIS), Lake Huron. Herein, euxinic waters resemble early-Earth ocean conditions, and diverse microbial groups form benthic mats. The goal of this study was to examine interspecific relationships among culturable cyanobacteria (two strains of Anagnostidinema) and diatoms (Craticula cuspidata and Nitzschia palea) isolated from MIS mats in a co-culture factorial experiment. Although most crosses showed limited interactions, a significant increase in abundance of one Anagnostidinema strain was found when grown with Craticula cuspidata compared to other taxa (P < 0.0001). Nitzschia palea growth was significantly reduced when grown with either strain of cyanobacteria (P = 0.0040). Addition of both cells and filtrates from C. cuspidata cultures caused increases in Anagnostidinema percent cover. Unique metabolic capabilities of C. cuspidata may benefit some cyanobacteria, and cyanobacteria may inhibit N. palea growth via interference competition. These interactions may be masked in the mat community in situ by environmental factors or other interspecific interactions, or allow species to survive in low abundance in an otherwise unfavorable habitat. [ABSTRACT FROM AUTHOR]

Niche partitioning according to time, space, or resources is the key to interspecific coexistence. Interactions among carnivore species are complex: interference is common, although positive relationships may develop through trophic facilitation. In turn, different behavioral responses to coexistence may be reported, ranging from avoidance to attraction, the outcome of which is highly dependent on the local environmental context. Here, we evaluated the temporal partitioning by analyzing spatiotemporal relationships between the red fox Vulpes vulpes and the European badger Meles meles in a Mediterranean?protected area for three full years, using intensive camera trapping. The two species showed similar temporal activity patterns, with a nocturnal activity and peaks at dawn and dusk. We found a substantial temporal overlap between red fox and badger (Δ > 0.78, on a 0‐1 scale). However, we detected some differences in temporal activity patterns across these species and no evidence of interspecific spatiotemporal avoidance. Previous work provided no evidence supporting spatial avoidance among the study species. Our results suggest a role of temporal partitioning at a finer scale during the night to facilitate interspecific coexistence. [ABSTRACT FROM AUTHOR]

Predator hunting strategies, such as stalking versus coursing behaviors, are hypothesized to influence antipredator behaviors of prey and can describe the movement behaviors of predators themselves. Predators and prey may alter their movement in relation to predator hunting modes, yet few studies have evaluated how these strategies influence movement behaviors of free‐ranging animals in a multiple‐predator, multiple‐prey system. We fit hidden Markov models (HMM) with movement data derived from >400 GPS‐collared ungulates and large predators in eastern Washington, USA. We used these models to test our hypotheses that stalking (cougars [Puma concolor]) and coursing (gray wolves [Canis lupus]) predators would exhibit different broad‐scale movement behaviors consistent with their respective hunting strategies in areas that increased the likelihood of encountering or capturing ungulate prey (e.g., habitats selected by deer [Odocoileus spp.]). Similarly, we expected that broadscale movement behaviors of prey would change in response to background levels of predation risk associated with each predator's hunting strategy. We found that predators and ungulate prey adjusted their broadscale movements in response to one another's long‐term patterns of habitat selection but not based on differences in predator‐hunting strategies. Predators changed their movement behaviors based on the type of prey, whereas ungulates generally reduced movement in areas associated with large predators, regardless of the predator's hunting strategy. Both predator and prey movements varied in response to landscape features but not necessarily based on habitat that would facilitate specific hunting behaviors. Our results suggest that predators and prey adjust their movements at broad temporal scales in relation to long‐term patterns of risk and resource distributions, potentially influencing their encounter rates with one another at finer spatiotemporal scales. Habitat features further influenced changes in movement, resulting in a complex combination of movement behaviors in multiple‐predator, multiple‐prey systems. [ABSTRACT FROM AUTHOR]

The article explores the role of ephemeral river islands in the Meta River in eastern Colombia as habitats for migratory songbirds from the northern and southern hemispheres during migration and the nonbreeding period. The islands emerge during the dry season, providing roosting and foraging sites for thousands of migratory birds. The study highlights the importance of understanding the habitat use and quality of nonbreeding areas for long-distance migrants and raises questions about the ecological associations, spatial-temporal dynamics, and conservation priorities of these ephemeral islands. [Extracted from the article]

The coevolutionary dynamic of host–parasite associations varies from strictly local adaptations to diffuse guild coevolution. How innate and acquired immune responses modulate host resistance to parasitism and how host specificity and geographic scaling affect the efficacy of host response have consequences for range dynamics and biological invasions.Using reciprocal transplant experiments, we tested whether local or diffuse coevolution shapes host response to parasitism in the host–parasite association between bitterling fishes and larval stages (glochidia) of freshwater mussels from Europe and East Asia.We found that glochidia initially indiscriminately attached to all study host species, but immune responses elicited significant differences in host responses within 24 h of infection, which intensified during glochidial development. European bitterlings were more resistant to European glochidia and Asian bitterlings to Asian glochidia, with the strongest geographic bias in resistance in the Asian bitterling hosts.This finding suggests a strong effect of local adaptation but also indicates the non‐negligible role of coevolutionary hotspots. Low natural glochidia load on bitterling species overall hence arise from competent immune response rather than glochidia avoidance behaviour. Bitterling immune response is primarily innate and not acquired.Overall, our data demonstrate the complex outcome of parasite pressure on the evolution of host resistance, and important role of geographically structured coevolution in shaping host response. [ABSTRACT FROM AUTHOR]

Summary Forest soils play a pivotal role as global carbon (C) sinks, where the dynamics of soil organic matter (SOM) are significantly influenced by ectomycorrhizal (ECM) fungi. While correlations between ECM fungal community composition and soil C storage have been documented, the underlying mechanisms behind this remain unclear. Here, we conducted controlled experiments using pure cultures growing on naturally complex SOM extracts to test how ECM fungi regulate soil C and nitrogen (N) dynamics in response to varying inorganic N availability, in both monoculture and mixed culture conditions. ECM species dominant in N‐poor soils exhibited superior SOM decay capabilities compared with those prevalent in N‐rich soils. Inorganic N addition alleviated N limitation for ECM species but exacerbated their C limitation, reflected by reduced N compound decomposition and increased C compound decomposition. In mixed cultures without inorganic N supplementation, ECM species with greater SOM decomposition potential facilitated the persistence of less proficient SOM decomposers. Regardless of inorganic N availability, ECM species in mixed cultures demonstrated a preference for C over N, intensifying relatively labile C compound decomposition. This study highlights the complex interactions between ECM species, their nutritional requirements, the nutritional environment of their habitat, and their role in modifying SOM. [ABSTRACT FROM AUTHOR]

This study investigates the diversity and ecological dynamics of macroalgae in Maxwell Bay, King George Island, Antarctica, focusing on species distribution, substrate composition, and interspecific interactions. Across nine survey sites, 31 macroalgal species were recorded, with 12 species identified as significant due to their considerable relative frequency, coverage, and biomass. Palmaria decipiens was the most dominant species in terms of frequency and coverage, while Desmarestia anceps had the highest biomass. The study revealed distinct substrate preferences, with P. decipiens favoring cobble and mud substrates, and Himantothallus grandifolius associating predominantly with pebble substrates. A core group of species, including Plocamium sp., H. grandifolius, Picconiella plumosa, Iridaea sp., and Trematocarpus antarcticus, exhibited strong ecological interactions characterized by high substrate similarity and mutual affinity. In contrast, pioneer species like P. decipiens and Monostroma hariotii showed lower affinity with other species, reflecting their early successional roles. These findings enhance our understanding of the complex interspecific relationships within Antarctic macroalgal assemblage and provide valuable baseline data for future ecological studies in the region. [ABSTRACT FROM AUTHOR]

What do seabirds perceive about the world? How do they do so? And how do they use the information available to them to make foraging decisions? Social cues provide seabirds with information about the location of prey. This can, of course, be passive and not involve higher‐order cognitive processes (e.g. simple conspecific or heterospecific attraction). However, seabirds display many behaviours that promote learning and the transmission of information between individuals: the vast majority of seabirds are colonial living, have an extended juvenile phase that affords them time to learn, routinely form intra‐ and interspecific associations, and can flexibly deploy a combination of foraging tactics. It is worth evaluating their foraging interactions in light of this. This review describes how seabirds use social information both at the colony and at sea to forage, and discusses the variation that exists both across species and amongst individuals. It is clear that social interactions are a critical and beneficial component of seabird foraging, with most of the variation concerning the way and extent to which social information is used, rather than whether it is used. While it may seem counterintuitive that large groups of potential competitors congregating at a patch can result in foraging gains, such aggregations can alter species dynamics in ways that promote coexistence. This review explores how competitive interference at a patch can be mitigated by behavioural modifications and niche segregation. Utilising others for foraging success (e.g. via social cues and facilitation at a patch) is likely to make population declines particularly damaging to seabirds if the quantity or quality of their social foraging interactions is reduced. Environmental changes have the potential to disrupt their social networks and thus, how these species obtain food and transfer information. [ABSTRACT FROM AUTHOR]

Freshwater macroinvertebrates can connect tropical forests and stream food webs by consuming both terrestrially and aquatically produced foods, but direct observations of nocturnal feeding behavior in these natural ecosystems are rare. Observational data on decapods feeding behavior are limited partly because they are cryptic and often forage at night to avoid predators and competitors. We hypothesized that freshwater decapods forage on riparian fruit fall based on its relatively high energy and nutrient content. We used underwater cameras to video record night-time foraging under dim red light. Palm fruits (Acrocomia aculeata (Jacq.) Lodd. ex Mart.) were added to determine rates of feeding responses among crabs (Silviocarcinus australis Magalhães and Turkay, 1996) and shrimp (Macrobrachium amazonicum Heller, 1862) in a spring-fed, clear-water stream in the state of Mato Grosso do Sul, Brazil. Within 30 min, shrimp located the fruit, and within 60 min, crabs began shredding the pulp of the palm fruit. Crabs fed on the palm fruits, on average five times longer than shrimp and produced pieces of palm fruit pulp that some shrimp consumed without aggressively interacting with the crab. Small fish also consumed some palm pulp particles. This interaction network is an example of fruit-fall processing based on indirect facilitation among different types of consumers. [ABSTRACT FROM AUTHOR]

Globalisation, climate change and international trade are the factors contributing to the spread of Aedes albopictus (Diptera: Culicidae) and Ae. aegypti into new areas. In newly invaded habitats, these non‐native species can serve as arbovirus disease vectors or increase the risk of disease spill over. These mosquitoes continue to emerge in new areas where they have or will have overlapping ranges with other resident mosquito species. The study investigates how invasive Aedes mosquitoes compete with the native Culex pipiens in Türkiye, which might affect the overall mosquito population dynamics and disease transmission risks. Both Aedes species exhibited contrasting responses to interspecific competition with Cx. pipiens. While Ae. albopictus suffers reduced emergence primarily in larger containers with abundant food, Ae. aegypti surprisingly thrives in mixed cultures under all food conditions. Adult Cx. pipiens emergence drops by half against Ae. albopictus and under specific conditions with Ae. aegypti. Competition influences mosquito size differently across species and life stages. Culex pipiens females grow larger when competing with Ae. aegypti, potentially indicating resource advantage or compensatory strategies. However, Ae. albopictus size shows more nuanced responses, suggesting complex interactions at play. Understanding how invasive and native mosquitoes interact with each other can provide insights into how they adapt and coexist in shared habitats. This knowledge can inform effective control strategies. The study highlights the differential responses of invasive Aedes species and the potential for managing populations based on their competitive interactions with the native Cx. pipiens. It can contribute to improved monitoring and prediction systems for the spread of invasive mosquitoes and the associated disease risks. [ABSTRACT FROM AUTHOR]

Leaf litter microbes collectively degrade plant polysaccharides, influencing land–atmosphere carbon exchange. An open question is how substrate complexity—defined as the structure of the saccharide and the amount of external processing by extracellular enzymes—influences species interactions. We tested the hypothesis that monosaccharides (i.e. xylose) promote negative interactions through resource competition, and polysaccharides (i.e. xylan) promote neutral or positive interactions through resource partitioning or synergism among extracellular enzymes. We assembled a three-species community of leaf litter-degrading bacteria isolated from a grassland site in Southern California. In the polysaccharide xylan, pairs of species stably coexisted and grew equally in coculture and in monoculture. Conversely, in the monosaccharide xylose, competitive exclusion and negative interactions prevailed. These pairwise dynamics remained consistent in a three-species community: all three species coexisted in xylan, while only two species coexisted in xylose, with one species capable of using peptone. A mathematical model showed that in xylose these dynamics could be explained by resource competition. Instead, the model could not predict the coexistence patterns in xylan, suggesting other interactions exist during biopolymer degradation. Overall, our study shows that substrate complexity influences species interactions and patterns of coexistence in a synthetic microbial community of leaf litter degraders. [ABSTRACT FROM AUTHOR]

Microbes are key drivers of global biogeochemical cycles, and their functional roles arey dependent on temperature. Large population sizes and rapid turnover rates mean that the predominant response of microbes to environmental warming is likely to be evolutionary, yet our understanding of evolutionary responses to temperature change in microbial systems is rudimentary. Natural microbial communities are diverse assemblages of interacting taxa. However, most studies investigating the evolutionary response of bacteria to temperature change are focused on monocultures. Here, we utilize high-throughput experimental evolution of bacteria in both monoculture and community contexts along a thermal gradient to determine how interspecific interactions influence the thermal adaptation of community members. We found that community-evolved isolates tended toward higher maximum growth rates across the temperature gradient compared to their monoculture-evolved counterparts. We also saw little evidence of systematic evolutionary change in the shapes of bacterial thermal tolerance curves along the thermal gradient. However, the effect of community background and selection temperature on the evolution of thermal tolerance curves was variable and highly taxon-specific,with some taxa exhibiting pronounced changes in thermal tolerance while others were less impacted. We also found that temperature acted as a strong environmental filter, resulting in the local extinction of taxa along the thermal gradient, implying that temperature-driven ecological change was a key factor shaping the community background upon which evolutionary selection can operate. These findings offer novel insight into how community background impacts thermal adaptation. [ABSTRACT FROM AUTHOR]

Social interactions with heterospecifics can yield important insights into the flexibility of behaviour and the role of learning in communication. Recently, the honeybee dance, a unique symbolic communication system to communicate positions in space, has been shown to involve learning. We asked if this communication system could potentially be learned by members of a species not normally using this communication system, the bumblebee(Bombus terrestris)—indicating that learning might have been at the origins of dance communication. We used mixed-species colonies of bumblebees and honeybees (Apis millefera) to investigate how the readiness to first establish contact with dancers might develop in uninformed bumblebee foragers. Over a month of observations, we recorded and classified a series of behavioural patterns in newly emerged honeybees introduced into queenright bumblebee colonies. A small subset of the introduced honeybees was able to establish in the nests and displayed their typical behavioural patterns, including homing, dance communication, trophallaxis, and social grooming. Remarkably, grooming and trophallaxis were also displayed to heterospecifics, and bumblebees accepted both, including food offered through trophallaxis, even though this behaviour is not normally used by bumblebees. However, bumblebees never attended honeybees’ waggle dances. Our results contribute to insights about bee social behaviour and cognition by providing a fascinating example of the adaptive use and modification of innate behaviour. [ABSTRACT FROM AUTHOR]

Symbiotic relationships shape ecological communities and often involve more than two species. Yet few experimental studies examine the impact of symbioses involving three species, particularly any mediating role of third parties, and none involving symbioses of predators.We investigated experimentally the synergistic and antagonistic fitness effects of three symbiotic spider predators across a broad latitudinal range and involving different species combinations.The three‐dimensional web complex of Cyrtophora spiders is a habitat patch to different associates—species of Argyrodes and web‐building Leucauge spider guests. Our field experiments, which manipulated the presence of each guest species and determined the subsequent host weight change, revealed a remarkable consistency in fitness outcomes across the three populations, with the consequences of the interactions between two species depending upon the services provided by a third.Cyrtophora hosts intercepted more prey when web‐building Leucauge guests were present and thus gained more weight. In contrast, Argyrodes guests exerted a fitness cost on their Cyrtophora host, but only when Leucauge guests were absent. A comparison of the prey consumed by Cyrtophora hosts and Argyrodes guests revealed that their diets (reflected in the size of prey) overlapped less in the presence of Leucauge web‐building guests.Our novel experimental study highlights the importance of exploring synergistic effects in multi‐species symbioses. Read the free Plain Language Summary for this article on the Journal blog. [ABSTRACT FROM AUTHOR]

Conservation successes in Europe have sparked the recovery of apex predators, which may affect the populations of mesopredators. The mesopredator release hypothesis (MRH) predicts that a decline in apex predators triggers a ‘release’ of mesopredators from suppression. We expanded the MRH to include predictions of inverse responses following increases in apex predator abundance or distribution. We examined European mesopredator responses to changes in apex predator populations and evaluated the extended MRH's explanatory power. We examined the results of 47 studies on European predators for supporting evidence, mixed evidence, no evidence, or contrasting evidence for the extended MRH. Out of 38 apex predator – mesopredator pairings, 10 predominantly supported the extended MRH, while others provided limited or no support. In 23 instances across 17 pairings, mesopredator responses contradicted predictions. Initial findings suggest the extended MRH better predicts mesopredator responses in pairings with intermediate to large body size differences and in pairings where mesopredators primarily hunt. Our results reveal non‐uniform mesopredator responses to changing apex predator populations. This emphasises the complexity of predator interactions, which extends beyond suppression. We suggest the MRH's scope is more restricted than previously thought, cautioning against overreliance on the MRH as a default expectation for European mesopredator responses to apex predator population changes. [ABSTRACT FROM AUTHOR]

1. Ecosystem engineering freshwater bivalves, burrowing in the substratum and accumulating shell deposits, transform bottom habitats. Especially the invasive Asian bivalve Sinanodonta woodiana (SW), due to its rapid growth, large size, and high fecundity, can affect benthic communities. Here, we determined its effect on habitat selection and behaviour of endangered native bivalves, Anodonta cygnea and Unio tumidus. 2. We conducted laboratory preference assays (Experiment 1: choice between two substrata) exposing the native bivalves to pure sand (control), shells (several densities on the sand surface or burrowed), or living SW. Then, we tested their locomotion and burrowing (Experiment 2) on pure sand and substrata contaminated with shells or living SW. 3. In Experiment 1, native bivalves avoided shells, but not living SW. Burrowed and larger shells were avoided compared with those on the surface and smaller ones, respectively. 4. In Experiment 2, U. tumidus exposed to SW delayed activity initiation (in response to living bivalves), increased locomotion (living bivalves, surface shells), and reduced burrowing depth (living bivalves, all shells). Anodonta cygnea exposed to SW reduced locomotion speed (living bivalves, shells), and reduced burrowing duration (burrowed shells) and depth (living bivalves, burrowed shells). 5. SW (especially shell beds) constitutes another emerging threat to native bivalves, impairing their burrowing and inducting active avoidance. As SW expands its distribution with climate warming, the range and strength of its impact is likely to increase, reducing the area available to native bivalves, exposing them to environmental dangers (due to burrowing limitation) and deteriorating physical condition (energetic resources used for excessive locomotion). [ABSTRACT FROM AUTHOR]

Birds and ants co‐occur in most terrestrial ecosystems and engage in a range of interactions. Competition, mutualism and predation are prominent examples of these interactions, but there are possibly many others that remain to be identified and characterized. This study provides quantitative estimates of the frequency of toe amputations resulting from ant bites in a population of migratory red‐necked nightjars (Caprimulgus ruficollis) monitored for 15 years (2009–2023) in S Spain, and identifies the attacker(s) based on taxonomic analyses of ant‐mandible remains found on injured toes. Less than 1% of examined adults (N = 369) missed one or more toes. The analysis of ant remains identified African army ants (Dorylus sp.) as the primary cause of toe amputations in nightjars and revealed that body parts of the attacker may remain attached to the birds even after intercontinental migration. No cases of severe damage were observed in juveniles (N = 269), apart from the mandible of a Messor barbarus – a local ant species – attached to one of the teeth of the characteristic comb of the medial toe of nightjars. The incidence of ant‐bite damage may appear unimportant for nightjar populations, but this might not be true if only birds that manage to survive their injuries and potential complications (e.g. severe bleeding and sepsis from opportunistic infections) return from the tropics. More field studies, ideally in tropical areas, that incorporate routine examination of ant‐induced injuries into their protocols are needed to understand the true incidence and eco‐evolutionary implications of antagonistic ant‐bird interactions. [ABSTRACT FROM AUTHOR]

Behavioural interactions between alien invasive fishes and native fishes is considered one of the drivers of native fish decline. However, there are few experimental studies on their behavioural interactions at the individual level. In this study, we investigated the behavioural interactions between the threatened native killifish Valencia letourneuxi, and the alien invasive Eastern mosquitofish Gambusia holbrooki, thought to induce the killifish's rapid population decline. The aim was to assess aggressive behaviours, disruption in activity, stress levels, boldness, forging efficiency and shelter use by the native fish in the presence of the mosquitofish. Interspecies interactions were assessed in a three-tiered experimental setup, i.e. in an empty arena, in the presence of an artificial cover, and during feeding, using two opponents at each trial. The behaviours recorded and assessed were nips, following, approach, moving/immobile, top/bottom, erratic movement, cover use, feeding and latency to exit. The results showed that the mosquitofish was bolder, followed the native species, spent significantly less time under the cover and consumed food, as opposed to no following by the native species, significantly higher cover use and time immobile, as avoidance behaviours, and zero feeding in the presence of the mosquitofish. More significantly, the native species received direct aggression by the mosquitofish, as opposed to no aggression at all exhibited by it. Future research needs, as well as the conservation implications of our findings are briefly discussed. [ABSTRACT FROM AUTHOR]

Secondary forests are increasingly important for biodiversity conservation and ecosystem functioning. Yet, we know little on how species interactions shift across the wide range of life history strategies in the context of forest succession, especially for non‐trophic animal social systems.Using data from mixed‐species flocks (hereafter MSFs) and life history and morphological traits from the 'fast‐slow' continuum, we utilized a novel combination of network theory and trait‐based ecology to examine the assembly of associations of MSFs among species with different fast‐slow strategies across stages of forest succession that exhibit different degrees of forest complexity.MSFs formed the most connected and cohesive network in the intermediate successional stage. In contrast, we observed the least connected and cohesive network in the early stage, and a strongly connected but intermediately cohesive network in the late stage. Fast species with smaller body size and mass, and larger clutch size, were gradually replaced by slow species during succession. Interspecific associations generally shifted from those among similarly fast species (early stage) to associations between fast and slow species (intermediate stage), and finally to those among similarly slow species (late stage).We suggest that vegetation complexity (e.g. tree size, height, diversity and canopy cover), related to the availability of resources and number of niches, shaped the network structure and functional composition of MSFs. Although the late successional forests play an irreplaceable role in protecting forest specialists (i.e. slow species), intermediate stage forests should be also protected, because the large‐sized networks formed by MSFs at intermediate stages can simultaneously conserve more species with varying ecological strategies. Read the free Plain Language Summary for this article on the Journal blog. [ABSTRACT FROM AUTHOR]

Species interactions such as facilitation and competition play a crucial role in driving species range shifts. However, density dependence as a key feature of these processes has received little attention in both empirical and modelling studies. Herein, we used a novel, individual‐based treeline model informed by rich in situ observations to quantify the contribution of density‐dependent species interactions to alpine treeline dynamics, an iconic biome boundary recognized as an indicator of global warming. We found that competition and facilitation dominate in dense versus sparse vegetation scenarios respectively. The optimal balance between these two effects was identified at an intermediate vegetation thickness where the treeline elevation was the highest. Furthermore, treeline shift rates decreased sharply with vegetation thickness and the associated transition from positive to negative species interactions. We thus postulate that vegetation density must be considered when modelling species range dynamics to avoid inadequate predictions of its responses to climate warming. [ABSTRACT FROM AUTHOR]

Interspecific interactions can influence species' activity and movement patterns. In particular, species may avoid or attract each other through reactive responses in space and/or time. However, data and methods to study such reactive interactions have remained scarce and were generally limited to two interacting species. At this time, the deployment of camera traps opens new opportunities but adapted statistical techniques are still required to analyze interaction patterns with such data. We present the multivariate Hawkes process (MHP) and show how it can be used to analyze interactions between several species using camera trap data. Hawkes processes use flexible pairwise interaction functions, allowing us to consider asymmetries and variations over time when depicting reactive temporal interactions. After describing the theoretical foundations of the MHP, we outline how its framework can be used to study interspecific interactions with camera trap data. We design a simulation study to evaluate the performance of the MHP and of another existing method to infer interactions from camera trap‐like data. We also use the MHP to infer reactive interactions from real camera trap data for five species from South African savannas (impala Aepyceros melampus, greater kudu Tragelaphus strepsiceros, lion Panthera leo, blue wildebeest Connochaetes taurinus and Burchell's zebra Equus quagga burchelli). The simulation study shows that the MHP can be used as a tool to benchmark other methods of interspecific interaction inference and that this model can reliably infer interactions when enough data are considered. The analysis of real data highlights evidence of predator avoidance by prey and herbivore–herbivore attraction. Lastly, we present the advantages and limits of the MHP and discuss how it can be improved to infer attraction/avoidance patterns more reliably. As camera traps are increasingly used, the multivariate Hawkes process provides a promising framework to decipher the complexity of interactions structuring ecological communities. [ABSTRACT FROM AUTHOR]

Metacommunity theory seeks to explain how local and regional processes contribute to the organisation of biological communities. Recent conceptual frameworks of this theory indicate that the dynamics of populations and communities are jointly established by dispersal, species responses to environmental conditions and biotic interactions dependent on species density. Here, we use hierarchical joint species distribution modelling to verify the effects of environmental factors (at multiple spatial scales), drainage network configuration, spatial autocorrelation and interspecific interactions on the structure of fish assemblages in terra‐firme streams in the Eastern Brazilian Amazon. Thirty streams were sampled in two field surveys, and 89 species were collected in total. Our results confirm the effects of limited dispersal, environmental conditions (at multiple scales) and the configuration of the drainage network on the dynamics of these assemblages. Furthermore, our results suggest that interspecific interactions are less relevant for the structuring of fish metacommunities in small Amazonian headwater streams. Abiotic factors like drainage networks and environmental heterogeneity were better predictors of species distributions than co‐occurrence patterns with potential competitors or predators. [ABSTRACT FROM AUTHOR]

We observed this behaviour, previously studied only in North America and as a rare occurrence, on each of the three visits, one per year, we made to the same site, in Italy. Honey bees Apis mellifera L. preferred collecting pollen from red-tailed bumble bees Bombus lapidarius L. than directly from flowers of the woolly thistle Cirsium eriophorum (L.). In another site, which equally had this thistle species as the only plant in bloom, but fewer bumble bees, honey and bumble bees foraged concomitantly on the same flowers avoiding interspecific contacts. In both sites, the honey bees showed easier foraging in the presence of male, than of less tolerant worker, bumble bees. In a third site, the honey bees preferred foraging independently on the smaller flowers of the Tyrol thistle Centaurea nigrescens Willd., while the bumble bees preferred the woolly thistle. Therefore, when plants offer few foraging choices, honey bees may visit less preferred large composite flowers where a crowd of bumble bees hampers their usual foraging mode, but little-reactive males offer pollen collection from their furry bodies, to which honey bees specialize. [ABSTRACT FROM AUTHOR]

Research Highlight: Jachowski, D. S., Marneweck, C. J., Olfenbuttel, C., & Harris, S. N. (2024). Support for the size‐mediated sensitivity hypothesis within a diverse carnivore community. Journal of Animal Ecology, https://doi.org/10.1111/1365‐2656.13916. A current paradigm in ecological research suggests that top predators are suitable sentinel species to identify ecosystem dysfunctions and monitor the effects of climate change. However, the adequacy of top predators to systematically take this function may be mistakenly inferred or unintentionally conflated from the fact that these species are regarded as biodiversity indicators or keystone, umbrella and flagship species in most ecosystems. Regarding terrestrial mammalian carnivores (order Carnivora), some researchers recently suggested that the smaller species likely possess a higher sensitivity to environmental changes than large carnivores because of their biological attributes and their intermediate position in food webs. To test this hypothesis, Jachowski et al. (2024) used camera trapping followed by occupancy and structural equation modelling to explore the dynamics of a diverse carnivore community and the factors that influence them. Their results confirmed that small carnivores are more sensitive to habitat changes and are interconnected by a greater number of significant pathways compared with larger carnivores. This support for the size‐mediated sensitivity hypothesis strengthens the proposition that small carnivores (and other mid‐rank predators) are ideal sentinel species for monitoring the effects of the wide range of contemporary and future environmental changes. Time will tell whether this new 'middle‐out ecology' paradigm will be considered in future global change studies. [ABSTRACT FROM AUTHOR]

Competition over resources often leads to intra‐ and interspecific interactions, which can be detrimental to the individuals involved. Thus, natural selection should favor communication systems that reliably convey information regarding the relative competitive abilities of an individual, reducing the need for physically damaging confrontation. Body size, sex, age, relatedness, and ornamentation are important factors determining dominance across diverse taxa in intraspecific interactions. These traits, when perceptible, may serve as signals across species in guilds that have frequent interspecific interactions. Hummingbirds provide a tractable system to study such community dynamics due to their high frequency of interactions, variable ornamentation, diverse body sizes, fast metabolism, and large overlap in resource utilization. Even in this system, potential interactions between morphology and coloration are rarely accounted for together when analyzing dominance between species. We take a novel approach to understanding interspecific dominance by assessing behavior, morphology, and coloration across different types of behavioral interactions. Across 11 tropical montane hummingbird species, we find that dominance is predicted by wing size and some metrics of plumage coloration. However, the biological significance of these factors varies between the different dominance behaviors performed. These results inform our understanding of interspecific signaling and its role in the evolution of intraguild communication and resource competition. [ABSTRACT FROM AUTHOR]

Palaeomycological material has rarely been reported in Mexican localities, especially parasitic fungi. In this paper, we present the first formal report of an interaction between an entomopathogenic fungus and an insect trapped in the Miocene amber from Chiapas, Mexico. The described syninclusion corresponds to two well-developed fungal fruiting bodies and a third one in development, assigned to the order Hypocreales (Ascomycota: Sordariomycetes), emerging from the thorax and abdomen of a termite (Blattodea: Mastotermitidae). This syninclusion represents a remarkable example of biological interactions in ancient tropical environments reflected in the fossil record. [ABSTRACT FROM AUTHOR]

Although the advent of high‐resolution GPS tracking technology has helped increase our understanding of individual and multispecies behavior in wildlife systems, detecting and recording direct interactions between free‐ranging animals remains difficult. In 2023, we deployed GPS collars equipped with proximity sensors (GPS proximity collars) on brown bears (Ursus arctos) and moose (Alces alces) as part of a multispecies interaction study in central Sweden. On 6 June, 2023, a collar on an adult female moose and a collar on an adult male bear triggered each other's UHF signal and started collecting fine‐scale GPS positioning data. The moose collar collected positions every 2 min for 89 min, and the bear collar collected positions every 1 min for 41 min. On 8 June, field personnel visited the site and found a female neonate moose carcass with clear indications of bear bite marks on the head and neck. During the predation event, the bear remained at the carcass while the moose moved back and forth, moving toward the carcass site about five times. The moose was observed via drone with two calves on 24 May and with only one remaining calf on 9 June. This case study describes, to the best of our knowledge, the first instance of a predation event between two free ranging, wild species recorded by GPS proximity collars. Both collars successfully triggered and switched to finer‐scaled GPS fix rates when the individuals were in close proximity, producing detailed movement data for both predator and prey during and after a predation event. We suggest that, combined with standard field methodology, GPS proximity collars placed on free‐ranging animals offer the ability for researchers to observe direct interactions between multiple individuals and species in the wild without the need for direct visual observation. [ABSTRACT FROM AUTHOR]

Prey adjust their antipredator behavioral tactics to minimize the risk of an encounter with predators. Spatiotemporal responses of prey to predators have been reported, but the nature of antipredator response is not ubiquitous and it is the object of increasing interest, especially considering the recent recovery of large carnivores in Europe, and the potential for behavioral antipredator responses to elicit consequences at the ecosystem level. We have tested multiple antipredator responses by fallow deer Dama dama to wolf Canis lupus in a Mediterranean protected area recently recolonized by this apex predator. Through intensive camera trapping, we tested for temporal and spatial association between predator and prey, and we have also studied deer vigilance in forest habitats where focal observations are usually impossible. Wolf detection rates were spatially associated with those of fallow deer. Accordingly, no evidence was found for fallow deer avoiding sites with higher predator detection rates. Temporal activity patterns were significantly different between the 2 species, with the wolf being mainly nocturnal whereas fallow deer was active especially during daylight. A comparison with a preliminary study strongly suggests an increase in the diurnal activity of fallow deer along with the stabilization of wolf presence in the area. Both the rate and the duration of vigilance of female fallow deer increased with the local frequency of wolf activity. We suggest an antipredator response based on temporal—rather than spatial—avoidance, as well as increased vigilance. [ABSTRACT FROM AUTHOR]

Host–parasite dynamics involve coevolutionary arms races, which may lead to host specialization and ensuing diversification. Our general understanding of the evolution of host specialization in brood parasites is compromised by a restricted focus on bird and insect lineages. The cuckoo catfish (Synodontis multipunctatus) is an obligate parasite of parental care of mouthbrooding cichlids in Lake Tanganyika. Given the ecological and taxonomic diversity of mouthbrooding cichlids in the lake, we hypothesized the existence of sympatric host‐specific lineages in the cuckoo catfish. In a sample of 779 broods from 20 cichlid species, we found four species parasitized by cuckoo catfish (with prevalence of parasitism of 2%–18%). All parasitized cichlids were from the tribe Tropheini, maternal mouthbrooders that spawn over a substrate (rather than in open water). Phylogenetic analysis based on genomic (ddRAD sequencing) and mitochondrial (Dloop) data from cuckoo catfish embryos showed an absence of host‐specific lineages. This was corroborated by analyses of genetic structure and co‐ancestry matrix. Within host species, parasitism was not associated with any individual characteristic we recorded (parent size, water depth), but was costly as parasitized parents carried smaller clutches of their own offspring. We conclude that the cuckoo catfish is an intermediate generalist and discuss costs, benefits and constraints of host specialization in this species and brood parasites in general. [ABSTRACT FROM AUTHOR]

Invasive species and chemical pollution both threaten biodiversity. Here, we discuss how pollution, through its impacts on wildlife behaviour, shapes invasion dynamics by altering species interactions. Addressing knowledge gaps will have implications for the management of invasive species and conservation of native ecosystems in an increasingly toxic world. [ABSTRACT FROM AUTHOR]

Aim: Occurring in five distinct global regions, Mediterranean‐type ecosystems (MTEs) include both centres of agricultural production and hotspots of extratropical biodiversity – particularly for plants and bees. Considerable research has addressed the persistence of highly diverse biological communities within MTEs, despite their typically long histories of anthropogenic and natural disturbance. However, important questions remain, especially regarding the limits of ecological resilience in the face of accelerating environmental change. Here, we explore current knowledge regarding the effects of disturbance on MTE plant–pollinator communities. Location: Mediterranean Basin, California, Cape Province in South Africa, Central Chile and Southern South‐Western Australia. Taxa Studied: Flowering plants and pollinators (insects, birds and mammals). Methods: We reviewed the available literature about MTE plant–pollinator communities via a systematic search that yielded 234 case studies. We analysed this dataset to quantify research efforts across regions and taxonomic groups, the proportion of surveys addressing ecological interactions (i.e. rather than only taxonomic diversity) and the availability of work addressing community responses to specific stressors (viz. climate change, landscape alteration, fire, farming, grazing, urbanization and species introductions). Results: Current knowledge on MTE plant–pollinator communities is dominated by work from the northern Mediterranean Basin, while the Southern Hemisphere and California are markedly understudied by comparison. Taxonomic coverage is similarly uneven, with 58% of studies focusing only on a single pollinator group. Furthermore, less than half of the surveys address ecological networks. Finally, despite some pioneering work addressing fire, climate and species introductions, only 13% focus on the impact of stressors on interaction networks. Outlook: Based on our findings, we identify a need for coordinated international research efforts focusing on (i) community‐level studies, observational and experimental, (ii) ecological networks, (iii) functional traits mediating post‐disturbance recovery and (iv) impacts of combined/synergistic stressors. Progress in these areas will facilitate predictions about the long‐term impacts of global change on MTE plant–pollinator communities. [ABSTRACT FROM AUTHOR]

Shelter building caterpillars act as ecosystem engineers by creating and maintaining leaf shelters, which are then colonized by other arthropods. Foliage quality has been shown to influence initial colonization by shelter-building caterpillars. However, the effects of plant quality on the interactions between ecosystem engineers and their communities have yet to be studied at the whole plant level. We examined how leaf tying caterpillars, as ecosystem engineers, impact arthropod communities on Quercus alba (white oak), and the modifying effect of foliage quality on these interactions. We removed all leaf tying caterpillars and leaf ties on 35 Q. alba saplings during the season when leaf tying caterpillars were active (June–September), and compared these leaf tie removal trees to 35 control trees whose leaf ties were left intact. Removal of these ecosystem engineers had no impact on overall arthropod species richness, but reduced species diversity, and overall arthropod abundance and that of most guilds, and changed the structure of the arthropod community as the season progressed. There was an increase in plant-level species richness with increasing number of leaf ties, consistent with Habitat Diversity Hypothesis. In turn, total arthropod density, and that of both leaf tying caterpillars and free-feeding caterpillars were affected by foliar tannin and nitrogen concentrations, and leaf water content. The engineering effect was greatest on low quality plants, consistent with the Stress-Gradient Hypothesis. Our results demonstrate that interactions between ecosystem engineering and plant quality together determine community structure of arthropods on Q. alba in Missouri. [ABSTRACT FROM AUTHOR]

We analyzed the influences of interspecific interactions and environmental factors on rodent community assembly in Mojave Desert wetlands that support the endangered Amargosa vole (Microtus californicus scirpensis). A total of 4927 rodents in six species were captured from 2010 to 2021 within 15 marshes, most frequently including Amargosa voles, harvest mice (Reithrodontomys megalotis), and house mice (Mus musculus), an invasive species. The structure of the community varied considerably over time and by marsh, driven mainly by reductions in harvest mice and increases in Amargosa voles and house mice between 2014 and 2017, and then reductions in Amargosa voles between 2018 and 2021. Northern marshes were dominated by voles, and southern marshes by house mice. Primary determinants of rodent capture rates were interspecific interactions, human proximity, and season. There was a significant inverse relationship between vole and house mouse captures per session, suggesting competitive exclusion. Distance to the nearest town was positively associated with the numbers of voles and negatively associated with the numbers of harvest mice, suggesting that voles may be more sensitive to human disturbance than other rodents. Amargosa voles and harvest mice had annual population cycles with peaks between July and September occurring 6–7 months after rainfall. Our results allow for valuable insight into the influences on community dynamics in desert rodents and highlight that conservation efforts that support Amargosa voles may simultaneously help control house mouse abundance and expansion. [ABSTRACT FROM AUTHOR]

The Florida Scrub-Jay (Aphelocoma coerulescens) and the Southeastern American Kestrel (Falco sparverius paulus) are imperiled species of conservation concern that occur sympatrically in Florida scrub habitat. Despite their overlap in scrub habitat, little information is available about agonistic encounters between these species. During concurrent bird research projects in Ocala National Forest, we opportunistically noted 18 interactions where the two species came within 10 m of each other. These primarily consisted of one species simply displacing the other from a perch without pursuit, and both species initiated these interactions. We found no evidence that Southeastern American Kestrels pose a threat to Florida Scrub-Jays, especially given their small size relative to the scrub-jay and their predominantly invertebrate diet. More fine-scale observations are needed to understand potential benefits that the species might accrue through their coexistence. [ABSTRACT FROM AUTHOR]

Simple Summary: Negative interactions between humans and wildlife pose a significant challenge to their coexistence. Although dog walking brings millions of people to public open spaces, roaming unleashed dogs threaten urban birds. Leashes for dogs in public parks remain controversial, with low compliance rates. As a practical solution, leashes could reduce fear among urban birds and enhance their coexistence with humans and dogs. Park leashing laws would be more likely to be enforced if there was a better understanding of how leashing laws benefit birds and wildlife. There is, however, no evidence that birds are less fearful of dogs because they understand the function of a dog's leash. Using a common urban bird in public parks in a major Australian city, we standardized human and dog approaches, both leashed and unleashed. The birds demonstrated an increased intensity of escape responses (for example, flight) when dogs were unleashed compared to leashed. By leashing dogs in parks, coexistence between people and birds would be enhanced. Controversy exists around owned dogs' impacts in public open spaces, with concerns about dogs' impact on wildlife, including birds. Leashing dogs in public open spaces offers a tractable way of reducing dogs' deleterious impacts on birds. Although dogs in public spaces are often unleashed, some dogs roam freely, whilst other unleashed dogs remain close to their owners. It is currently unknown whether birds can perceive and incorporate subtle differences in the leash status of approaching, but non-roaming, dogs into their escape decisions. We compare escape responses of a common urban bird, the magpie-lark Grallina cyanoleuca, in parks in Melbourne, Australia, to standardized approaches by a walker and a dog, which was either leashed or not leashed (but with the dog at the same distance from the walker). Flight-initiation distances, the distance between the lark and dog when escape commenced, did not vary between treatments. However, the unleashed dog evoked more intense responses (mostly flying away) than the leashed dog (mostly walking away). Thus, this species appears to perceive unleashed dogs as especially threatening, independent of their roaming behavior. Our findings suggest that leashing may be an effective way to reduce dog disturbance to wildlife, even for non-roaming dogs. [ABSTRACT FROM AUTHOR]

Phoretic mites attach to different body parts of the red palm weevil (RPW), Rhynchophorus ferrugineus (Olivier, 1790), to disperse. However, the question of how the patterns of attachment sites are formed remains intriguing. Here, we examined RPW‐associated phoretic mites in four districts in Northern Portugal (macrohabitat), and investigated the patterns of mite distribution on six body parts of RPW (microhabitat). At the macrohabitat level, we detected seven phoretic mite taxa using the RPW host in each of the four studied districts, all documented for the first time in association with this invasive exotic species in Portugal. However, their relative abundance (species evenness) varied between districts, as did species diversity. All examined weevils carried mites, and the prevalence of the different taxa did not differ between districts or sex of weevils. Measured by mean abundance and degree of aggregation, Centrouropoda sp. proved to be the dominant taxon, while Acarus sp. and Curculanoetus rhynchophorus were considered common subordinate taxa and Uroovobella sp., Mesostigmata, Nenteria extremica and Dendrolaelaps sp. sparse taxa. At the microhabitat level, all taxa were present on all body parts of the RPW; the highest abundance was in a region encompassing the inner surface of the elytra and the membranous hind wings (subelytral space). Analysis of niche overlap revealed that the distribution patterns of phoretic mite taxa on the RPW were not randomly structured. In the subelytral space, interspecific coexistence of mites increased as a function of body size difference with the dominant Centrouropoda sp. We found that in the subelytral space the large dominant species Centrouropoda sp. displaced the larger species Uroobovella sp. and the similarly sized species Nenteria extremica, but coexisted with smaller taxa. [ABSTRACT FROM AUTHOR]

The introduction of species is a leading cause of biodiversity loss and habitat alteration. Several species have invaded Mexican freshwater ecosystems, adversely affecting native fishes. Specifically, in the Amacuzac River of the Balsas Basin (Central Mexico), at least four non-native cichlids have been recorded: tilapia Oreochromis sp., convict cichlid Amatitlania nigrofasciata, spotcheek cichlid Thorichthys maculipinnis, and green terror Andinoacara rivulatus. These species co-occur with the Mexican mojarra Amphilophus istlanus, the only native cichlid in the Basin. Invasive cichlids compete for resources such as shelter and food, and prey on offspring of the Mexican mojarra. In the presence of invasive cichlids, the costs and risks of foraging and finding available shelter increase for the native cichlid. Predation pressure from invasive cichlid fishes on the Mexican mojarra increases the time invested by parents in caring for offspring and their stress levels, potentially contributing to Mexican mojarra population declines. Here, we gathered the best evidence available to discuss some mechanisms and consequences of such co-occurrences in relation to reproductive behaviors, parental care, competition for resources, and dominance hierarchy, and how the four invasive cichlids have negatively affected the Mexican mojarra. [ABSTRACT FROM AUTHOR]

Interspecific adoption is an intriguing topic in behavioral and evolutionary ecology. As it is a rare phenomenon, seldom documented in the literature, reports of interspecific adoption based on solid data are particularly valuable. A long‐term and extensive monitoring programme involving a local population of European blackbirds (Turdus merula, hereafter blackbird) has yielded, among other things, observations of alloparental behavior exhibited by blackbirds toward fieldfare (Turdus pilaris) nestlings (a single nest, the first‐ever record) and fledglings (12 cases in all). We discuss the observations in the context of the available literature. [ABSTRACT FROM AUTHOR]

Background and aims: Cereal-legume intercropping has significant advantages over the corresponding sole cropping patterns regarding efficient nitrogen utilization. However, a systematic theoretical and practical basis for improving the nitrogen use efficiency (NUE) in intercropping systems by optimizing nitrogen management is still lacking. Methods: The postponing N fertilizer topdressing on nitrogen interspecific competition and complementary in pea/maize intercropping was investigated. At the jointing stage and 15-d post-silking stage of maize (N3), 108 and 36 kg N ha− 1 were topdressing, respectively. During the jointing stage of N3, 72 kg N ha− 1 and 36 kg N ha− 1 were transferred to the 15-d post-silking stage, thus resulting in the N1 and N2 treatments. Results: The postponed N fertilizer topdressing enhanced the N accumulation of crops. Compared with N3, N1 treatment increased the N accumulation of pea/maize intercropping and monoculture maize by 19.3% and 18.5%, respectively. The N1 improved the nitrogen interspecific competition of intercropped pea and nitrogen recovery growth of intercropped maize. The N accumulation in the intercropping system is a quadratic relationship with the nitrogen interspecific competition and a positive linear relationship with nitrogen recovery growth. Consequently, the grain yield and NUE of pea/maize intercropping with N1 increased by 27.3% and 78.8% compared to N3. Conclusion: The postponed N fertilizer topdressing, especially 72 kg N ha− 1 from the jointing stage to 15-d post-silking stage, can synergistically regulate the nitrogen interspecific competition of pea and the nitrogen recovery growth of maize. [ABSTRACT FROM AUTHOR]

Simple Summary: Satyrization, a form of sexual interaction between males of one species with females of another species, has attracted renewed interest in pest management strategies. By inducing fitness costs in one or both interacting species, satyrization may indeed dramatically affect population dynamics, being a valuable tool to be used alone, or in conjunction with other area-wide control approaches. Here, we aimed to investigate the potential use of satyrization to control the invasive pest Drosophila suzukii by using D. melanogaster males. By realizing courtship tests, spermathecae analysis, and multiple-choice experiments, we showed that D. melanogaster males were able to successfully court, mate and reduce the offspring of D. suzukii females. These results, overall, showed that the use of D. melanogaster males can be an effective tool to control D. suzukii and lay promising foundations for testing the application of this approach in field conditions. Drosophila suzukii represents one of the major agricultural pests worldwide. The identification of safety and long-lasting tools to suppress its populations is therefore crucial to mitigate the environmental and economic damages due to its occurrence. Here, we explore the possibility of using satyrization as a tool to control the abundance of D. suzukii. By using males of D. melanogaster, we realized courtship tests, spermathecae analysis, and multiple-choice experiments to assess the occurrence and extent of pre- and post-zygotic isolation between the two species, as well as the occurrence of fitness costs in D. suzukii females due to satyrization. Our results showed that: (i) D. melanogaster males successfully courted D. suzukii females; (ii) D. melanogaster males significantly affected the total courtship time of D. suzukii males, which reduced from 22.6% to 6.4%; (iii) D. melanogaster males were able to inseminate D. suzukii and reduce their offspring, inducing a high fitness cost. Reproductive interference occurs at different steps between D. melanogaster and D. suzukii, both alone and in combination with other area-wide control approaches. [ABSTRACT FROM AUTHOR]

The presence of other animals, both conspecifics and heterospecifics, is a major driving force for how animals organize themselves in space and time. Although theoretical models are available to explain the role of each in animal movement, fine-scale assessments of daily movement are scarce, particularly for primates. Hence, our goal was to assess whether and how the presence of conspecifics and heterospecifics influence spatiotemporal landscape use in two, wild, howler monkey (Alouatta guariba) groups. We followed the groups for 14 months in a large, continuous forest, during which we recorded their daily path length (DPL), home range, activity budget, feeding, and the presence of other groups (conspecifics) and other species (heterospecifics). The two groups differed in DPL, home range, proportion of fruits ingested, and time devoted to moving and resting. Partial least squares path modelling showed that variation in DPL was explained by the percentage of leaves or fruits ingested and by the presence of conspecifics, but not of heterospecifics. Group differences in several ecological variables emphasise the need to conduct further studies of space use with more groups in the same area to understand the underlying mechanisms of these differences. Moreover, our analysis shows that within-species interactions may be a stronger force in spatiotemporal organisation than interspecies interactions, at least in this folivorous primate. This is relevant from both a theoretical standpoint, and also when considering the consequences of habitat fragmentation and reduction. Deforestation leads to decreased resource availability and increased likelihood of encounters with conspecifics, which ultimately alters the proportion of food items ingested and increases the DPL, disrupting energy balance. [ABSTRACT FROM AUTHOR]

Background: There is need of information on ecological interactions that keystone species such as apex predators establish in ecosystems recently recolonised. Interactions among carnivore species have the potential to influence community-level processes, with consequences for ecosystem dynamics. Although avoidance of apex predators by smaller carnivores has been reported, there is increasing evidence that the potential for competitive-to-facilitative interactions is context-dependent. In a protected area recently recolonised by the wolf Canis lupus and hosting abundant wild prey (3 ungulate species, 20–30 individuals/km2, together), we used 5-year food habit analyses and 3-year camera trapping to (i) investigate the role of mesocarnivores (4 species) in the wolf diet; (ii) test for temporal, spatial, and fine-scale spatiotemporal association between mesocarnivores and the wolf. Results: Wolf diet was dominated by large herbivores (86% occurrences, N = 2201 scats), with mesocarnivores occurring in 2% scats. We collected 12,808 carnivore detections over > 19,000 camera trapping days. We found substantial (i.e., generally ≥ 0.75, 0–1 scale) temporal overlap between mesocarnivores—in particular red fox—and the wolf, with no support for negative temporal or spatial associations between mesocarnivore and wolf detection rates. All the species were nocturnal/crepuscular and results suggested a minor role of human activity in modifying interspecific spatiotemporal partitioning. Conclusions: Results suggest that the local great availability of large prey to wolves limited negative interactions towards smaller carnivores, thus reducing the potential for spatiotemporal avoidance. Our study emphasises that avoidance patterns leading to substantial spatiotemporal partitioning are not ubiquitous in carnivore guilds. [ABSTRACT FROM AUTHOR]

Developing approaches to simultaneously maximize short‐rotation woody crop (SRWC) productivity while minimizing footprints associated with intensive management is imperative to profitable and sustainable bioenergy production systems. Intercropping nitrogen (N)‐fixing cover crops in SRWC systems is an overlooked approach to sustainably intensify SRWC production by increasing N availability using less environmentally costly inputs. Here, we discuss how functional traits (e.g., seasonal activity, lifespan, leaf habit, soil exploration) of cover crops and SRWCs may interact through space and time influencing access to light, water, and nutrients to provide a framework for successful integration of cover crops into SRWCs. Next, we summarize the literature on intercropping forest plantations with N‐fixing cover crops to identity research gaps and outline future research needs and opportunities. And then, using empirical N demand and productivity data from SRWCs and cover crop N inputs from the literature, we illustrate how SRWC leaf habit (conifer evergreens and deciduous hardwoods) would influence successful integration of cover crops and potential N fixation. We estimate that integrating cover crops into SRWCs could supply 27% and 72% of the N demand across a 10‐year rotation for an evergreen and a deciduous hardwood, respectively. These figures suggest these integrated SRWC systems may approach a virtual minimal external N input when other biogeochemical cycles are considered. The guiding principles presented here are grounded in ecological theory and provide a framework for sustainable intensification of forest production. Our study discussed the potential of integrating nitrogen (N)‐fixing cover crops into short‐rotation woody crop (SRWC) systems as an alternative for ecological intensification of bioenergy production systems. Using ecological theory and numerical simulations, we explored how functional traits (e.g., seasonal activity, lifespan, leaf habit, soil exploration) of cover crops and SRWCs can influence competition for resources in space and time to provide a framework for successful integration of cover crops into SRWCs. Our simulations suggest integrated SRWC systems increase whole‐system N cycling potential and reduce external N demand, ultimately maximizing SRWC productivity while reducing greenhouse gas emissions and N pollution. [ABSTRACT FROM AUTHOR]

Birds' nests hold rich and diverse communities of invertebrates with complex interspecific interactions whose study could improve our understanding of food webs and resource dynamics. To reach this goal, identification of the participants of such interactions is basic but current knowledge on some key groups such as hymenopteran parasitoids is admittedly poor and unreliable. Here we describe the invertebrate fauna in nests of the Eurasian wryneck Jynx torquilla Linnaeus, 1758 (Piciformes: Picidae) and the relative importance of various trophic guilds. We found a rich community where ectoparasitic Diptera of birds, parasitoid wasps and scavenger Diptera had a prominent representation. We specifically studied the natural enemies of the most abundant bird ectoparasite Carnus hemapterus Nitzsch, 1818 (Diptera: Carnidae), which revealed that Kleidotoma caledonica Cameron, 1888 (Hymenoptera: Figitidae) is a specialized and frequent parasitoid of the ectoparasite. Information on the association between other parasitoid wasps, parasitoid flies and their hosts is also off ered. Such associations could result in trophic cascades with remarkable consequences for the avian host. [ABSTRACT FROM AUTHOR]

Long recognized as a threat to wildlife, particularly for large carnivores, livestock grazing in protected areas can potentially undermine conservation objectives. The interspecific interactions among livestock, snow leopards (Panthera uncia), and their wild prey in fragile Asian highland ecosystems have been a subject of debate. We strategically deployed 164 camera traps in the Wolong National Nature Reserve to systematically investigate the activities of snow leopards, their primary wild ungulate prey species, and free‐ranging livestock. We found that snow leopard habitat use was influenced by both wild prey and livestock. Blue sheep served as the main wild prey that spatially attracted snow leopards and coexisted with yaks while free‐ranging yaks significantly restricted snow leopard habitat use both temporally and spatially. This study challenges the conventional understanding that livestock indirectly impacts large carnivores by competing with and displacing wild prey. Our findings highlight that free‐ranging yaks within the alpine canyon terrain could directly limit snow leopard habitat use, suggesting a potential risk of grazing in reducing apex predator distribution and jeopardizing their populations. Consequently, managing their coexistence in shared habitats requires a more nuanced approach. Furthermore, our research underscores the importance of further research efforts aimed at enhancing our comprehension of the complex interplay within animal communities and ecosystems. This knowledge will contribute to the development of informed, evidence‐based conservation strategies and policies. [ABSTRACT FROM AUTHOR]

Simple Summary: This article studies the interaction between two parasites, a parasitoid (Sclerodermus guani) and an entomopathogenic fungus (Beauveria bassiana) on the same host, a longicorn beetle Monochamus alternatus. We focused on the survival and reproduction of the parasitoid's parent and its offspring fitness under different concentrations of B. bassiana suspension in the laboratory. The results show that S. guani parent females carrying higher concentrations of the pathogen shorten the pre-reproductive time and regulate their own fertility and their offspring's survival and development. Under the stress of the entomopathogenic fungus B. bassiana, the mortality effect of the parasitoid S. guani to its host M. alternatus was also assessed by the interspecific relationship model, which contained three dimensionless parameters: the ratio vulnerability, dilution ratio, and PR (the ratio of the total number of parasitoids successfully controlling host larvae M. alternatus to the total number of parasite events during parasitism). These findings shed light on the potential interspecific interactions between the two parasites which were able to coexist and communicate with their hosts in ecological contexts (with a high overlap in time and space) and cause interspecific competition and intraguild predation. Complex interspecific relationships between parasites and their insect hosts involve multiple factors and are affected by their ecological and evolutionary context. A parasitoid Sclerodermus guani (Hymenoptera: Bethylidae) and an entomopathogenic fungus Beauveria bassiana (Hypocreales: Cordycipitaceae) shared the same host in nature, Monochamus alternatus (Coleoptera: Cerambycidae). They often encountered the semi-enclosed microhabitat of the host larvae or pupae. We tested the survival and reproduction of the parasitoid's parent and its offspring fitness under different concentrations of B. bassiana suspension. The results show that S. guani parent females carrying higher concentrations of the pathogen shorten the pre-reproductive time and regulate their own fertility and their offspring's survival and development. This minimal model of the interspecific interactions contains three dimensionless parameters, vulnerability (θ), dilution ratio (δ), and PR, which were used to evaluate the mortality effect of the parasitoid S. guani on its host M. alternatus under the stress of the entomopathogenic fungus B. bassiana. We compared the infection and lethal effect of the fungus B. bassiana with different concentrations to the parasitoid S. guani and the host larvae M. alternatus. At higher concentrations of the pathogen, the parasitoid parent females shorten the pre-reproductive time and regulate their own fertility and their offspring's survival and development. At moderate concentrations of the pathogen, however, the ability of the parasitoid to exploit the host is more flexible and efficient, possibly reflecting the potential interspecific interactions between the two parasites which were able to coexist and communicate with their hosts in ecological contexts (with a high overlap in time and space) and cause interspecific competition and intraguild predation. [ABSTRACT FROM AUTHOR]

Interspecific interactions are major drivers shaping ecological communities. Nevertheless, understanding how and to what extent they affect ecosystem functioning remains a key challenge for both fundamental and applied ecology. In the context of agricultural biodiversity loss, sustaining populations of organisms that provide essential ecosystem services is crucial but remains challenging. Interactions among beneficial organisms may explain such results, as they impact organisms' fitness. These effects could accumulate when scaled up to the population level, modifying community structure and functioning. Interactions could also affect organisms' foraging behaviour and consequently their efficiency. Here, we review and synthesize the knowledge of the effect of interactions within and between two groups of ecosystem services providers: natural enemies and pollinators, respectively providing biological control of pests and crop pollination services. We show that intra-guild predation, competition and resource partitioning are common interactions structuring natural enemy communities, and may affect their effectiveness to control pests. Nevertheless, actual evidence in complex systems and long-term studies are still missing, and application in agricultural settings is only at its beginning. Similarly, competition and resource partitioning among pollinators is a recent focus of ecological research. Studying facilitative interactions is clearly missing. Finally, while we show that interactions between natural enemies and pollinators can theoretically happen in natura due to the use of similar resources and habitats, this question remains poorly addressed. We discuss future research perspectives to better capture the complexity of biodiversity effects on ecosystem functioning, and propose guidelines to the implementation of more efficient multi-service schemes in agroecological landscapes. [ABSTRACT FROM AUTHOR]

Since the fall armyworm (FAW) Spodoptera frugiperda invaded China, it has coexisted in maize fields with the native cotton bollworm (CBW) Helicoverpa armigera, but the population dynamics and competitive mechanisms between the two pests are not well understood. We evaluated interspecific competition between FAW and CBW by analyzing their bidirectional predation in the laboratory, survival rates when their larvae co-infested the same maize plant, and the population dynamics of both in the same maize field. In the predation tests, FAW and CBW larvae preyed on each other. However, the theoretical maximum predation of sixth-instar FAW larvae preying on first–second-instar CBW larvae was 71.4 and 32.3 individuals, respectively, while that of CBW was 38.5 and 28.6 individuals. The field co-infestation trials showed that the older larvae had a higher survival rate when the two pests co-infested the same maize plants, but young larval survival was higher for FAW than CBW. In the maize field from 2019 to 2021 in southern Yunnan, FAW populations were significantly higher than those of CBW. Our findings suggested that FAW larvae had a predation advantage over CBW, which might be an important reason for its dominance in Chinese maize fields. This result provides a scientific basis for developing a monitoring technology and for the integrated management of pests in invaded habitats of FAW. [ABSTRACT FROM AUTHOR]

Interspecific interactions can mediate site occupancy of sympatric species and can be a key factor in habitat use patterns. American martens (Martes americana) and Fishers (Pekania pennanti) are two sympatric mesocarnivores in eastern North American forests. Due to their larger size, fishers have a competitive advantage over martens. We investigated site occupancy of martens and fishers in temperate deciduous forests of Québec, an environment modified by forest management and climate change. We formulated hypotheses on the spatial distribution of the studied species based on the knowledge of local trappers and on the scientific literature regarding forest cover composition, habitat fragmentation, and competitive relationships. We used a network of 49 camera traps monitored over two fall seasons to document site occupancy by both species. We used two-species site occupancy models to assess habitat use and the influence of fishers on martens at spatial grains of different sizes. None of the habitat variables that we considered explained site occupancy by fishers. Availability of dense old coniferous stands explained the spatial distribution of martens both at the home range grain size and at the landscape grain size. We identified the characteristics of habitat hotspots based on the knowledge of trappers, which highlighted the importance of stand composition, height, age, and canopy closure. The characteristics of habitat hotspots for martens in temperate deciduous forests refine the habitat suitability model for American martens that was originally developed for boreal forests of Québec. [ABSTRACT FROM AUTHOR]

A novel interaction between a long‐tailed weasel (Mustela frenata) and a plains spotted skunk (Spilogale interrupta) carcass is detailed. In November 2020, a farmer in Edmunds County in north‐central South Dakota sent in a video recording of a long‐tailed weasel with a spotted skunk carcass. Location of the event, carcass condition, and recorded behavior of the long‐tailed weasel offer probable, but unconfirmed, evidence that the spotted skunk was killed by the long‐tailed weasel. [ABSTRACT FROM AUTHOR]