Basic and Applied Ecology

Numerous studies on plant-plant interactions aim to distinguish positive from negative effects, especially among related individuals. Most studies interpret a reduction in biomass when grown with related individuals as kin recognition. However, these interactions can shift from positive to negative depending on environmental or biotic factors. We investigated these interactions in Black poplar (Populus nigra L.), a riparian tree species growing in high densities and stressful habitats, by examining the effects of relatedness and water deficit during early developmental stages. We set up two experiments where seedlings from four kin groups were competing with related or unrelated individuals, in well-watered versus water deficit environment, and studied their response through growth, root nitrogen uptake and mycorrhizal diversity. The four kin groups exhibit similar intrinsic growth capacities. However, for two kin groups, we found differences in competitive ability. Thus, we found that individuals responded differently depending on whether they were grown with related or unrelated individuals. Water deficit did not change the outcomes of interactions. Differences in competitive ability between kin groups was the most parsimonious interpretation, thus eliminating kin recognition as an explanation. Our study suggests that results obtained in general in kin studies must be carefully analyzed and that alternative interpretations, such as differences in competitive ability, must be tested before conclude wrongly to kin recognition. Our study also suggests that mycorrhizal communities develop differently according to the kin groups considered and can potentially have impacts on the growth of individuals.

Polycultures have long been practiced in traditional agriculture, yet their ecology-based benefits have remained underexplored. Here, under realistic conditions, we experimentally evaluated the productivity and ecological interactions in cultivated milpa, a traditional Mesoamerican polyculture of maize, squash and beans, using a substitutive design in which total plant density was held constant while varying species composition. Specifically, we asked whether productivity gains arose through complementary or selection effects, and whether these gains were associated with changes in arthropod communities and herbivory. We additionally evaluated whether prior cultivation influenced maize performance in the following season. Milpa plots produced significantly higher total yields, more than 2.6 times those of monocultures, despite poor bean performance. In particular, squash and maize equivalent yields increased approximately threefold. We found that these improvements were mainly explained by complementary effects rather than selection effects. Arthropod communities responded in species-specific ways to crop diversity, with predator abundance tracking herbivore presence. However, no consistent patterns emerged between herbivore load, predator abundance and plant damage, suggesting that belowground plant interactions may play a more important role than top-down herbivore control in explaining complementarity effects. In the following season, maize yield increased by [~]30% in plots previously planted with squash or beans, with milpa plots showing intermediate responses. These findings demonstrate that milpa can substantially enhance productivity while generating benefits that extend into the advantages and soil into the following growing season. Overall, our results suggest that complementarity among crops is the primary driver of productivity in milpa under low-input conditions.

Repeated grazing and trampling can reduce forb populations in South African mesic grasslands by limiting photosynthesis and depleting carbohydrate reserves stored in underground organs. We examined the effects of repeated defoliation on growth, bulb starch reserves and water status in the geophyte Eucomis autumnalis over 468 days. Four intense summer and autumn defoliations reduced above-ground production, bulb mass, starch reserves and bulb water pools, with the strongest impacts occurring in late summer and autumn when plants normally replenish reserves. Repeated defoliation disrupted seasonal source sink dynamics, forcing resources into regrowth and driving bulbs towards energetic bankruptcy. These results highlight the importance of avoiding heavy autumn grazing and providing periodic full-year rests to conserve geophytic forbs in mesic grasslands.

O_LIFloral nectar plays a critical role in shaping the ecology and evolution of plant-pollinator interactions. Effective and efficient methods that allow for broad-scale sampling of nectar volume and sugar concentration across a diversity of taxa are needed to improve our understanding of many dimensions of mutualistic plant-pollinator interactions--including their basic ecology and evolution, their responses to environmental change, and their conservation and restoration. C_LIO_LIDespite the key importance of nectar for mediating plant-pollinator interactions, quantifying floral nectar in the field from many different plant species is challenging because there is often no one-size-fits-all sampling method that is effective across a diversity of floral structures and nectar traits. Different methods require different preparation, and sampling from many species involves a variety of logistical challenges. C_LIO_LIHere we provide a methodological roadmap for sampling floral nectar in the field from many different plant species. We describe our nectar collection methods in detail, including necessary equipment, calculations, and approaches appropriate for different floral morphologies. We also provide a troubleshooting guide for common problems encountered while collecting nectar in the field. To demonstrate the utility and effectiveness of our methods for collecting nectar from many different species, we present results on nectar trait variation from 53 species in an ecosystem. C_LIO_LIOur method illustrates that nectar traits vary considerably within and among plant species, indicating that large-scale nectar sampling projects are an important consideration for many basic and applied questions in pollination ecology and evolution. We hope that across many plant communities and ecosystems, our paper provides a practical roadmap for how to navigate the complexities of quantifying floral nectar traits. C_LI

Artificial light at night (ALAN) can alter the movement of nocturnal pollinators such as moths, with potential consequences for pollination services. However, most studies have focused on the presence or properties of lights, while the role of spatial lighting configuration remains poorly understood. We conducted a small-scale field experiment to test how different lighting configurations affect pollination success in moth-pollinated plants, using low-intensity LED garden lights. Potted phytometer plants of three moth-pollinated species were exposed to one of three treatments: no-light control, isolated LED point lights, or 25 m linear arrays of multiple LED lights. We quantified pollination success as both the probability of seed set and reproductive output through seed and capsule production. Experimental lighting affected plant reproductive success, with light arrays increasing seed-set probability, seed and seed capsule number relative to unlit controls, whereas point lights showed no clear effect. These results provide preliminary evidence that the spatial configuration of artificial lights may influence nocturnal pollination outcomes. Future work combining phytometer assays with direct tracking of moth movement is needed to assess whether light arrays facilitate or redirect the dispersal of nocturnal pollinators.

Global climate change has increased the frequency and intensity of drought events, making it urgent to understand how native species respond to water deficit (WD). In biodiverse environments such as tropical forests, simple methods are needed to study multiple species simultaneously. This can help predict how natural environments will respond to climate change and guide the strategic selection of drought-resistant species for reforestation. This study aimed to: (1) adapt an existing simple and inexpensive method to apply a controlled WD on tree seedlings from tropical species commonly produced in nurseries for restoration projects, suitable for greenhouse experiments; and (2) evaluate the effectiveness of this method in generating ecophysiological responses to WD that allow the estimation of species' drought resistance. Ten native tree species from the Semideciduous Seasonal Forest (SSF), a phytophysiognomy of the Atlantic Forest, were selected. An existing method was adapted to implement capillary irrigation, in which the bases of the seedling tubes were placed in floral foam blocks positioned inside 15 L plastic containers filled with water. A gradual and severe WD was applied to five seedlings of each species by removing all water from the containers, leaving only the water retained in the saturated floral foam available for plant uptake. The remaining seedlings were maintained well-watered (containers full and foam saturated) as the control group. Stomatal conductance (gs) was measured daily for all seedlings until they reached 50% or less of their initial gs (igs); at this point, stem water potential ({Psi}w) was measured. Both gs and {Psi}w differed significantly among treatments and species (p < 0.01). Ficus guaranitica and Heliocarpus popayanensis were the only species that did not show significant {Psi}w differences between treatments, indicating higher drought resistance. In contrast, Campomanesia xanthocarpa and Eugenia uniflora had the lowest {Psi}w values under WD, suggesting lower drought resistance. The remaining species were distributed along a gradient of responses to WD. Additionally, no correlation was found between {Psi}w and gs at 50% igs in the WD group (rho = 0.16, p = 0.26). The method proved effective in inducing controlled WD and generating measurable ecophysiological responses, offering a useful tool for screening native species for drought resistance.

Urban green spaces are increasingly recognised as important refuges for biodiversity, yet their ecological value depends strongly on design and management. Here, we investigate how fine-scale structural and microhabitat components shape urban ant assemblages, using ants as indicators of broader arthropod responses to urbanisation. Ant communities were sampled in twelve urban green spaces in Cordoba (southern Spain) over a ten-year period (2004 to 2013) using pitfall traps, alongside detailed characterisation of vegetation structure and ground-layer microhabitats. In total, 38 species and 25,578 individuals were recorded. Microhabitat variables explained 58% of the variation in species occurrence. Community differences among microhabitats were driven primarily by nestedness, with dense herbaceous cover acting as a core habitat and edge-related components contributing disproportionately to beta diversity. Tree abundance showed a unimodal relationship with species richness, with maximum diversity at intermediate densities, while shrub and lawn cover had weak or inconsistent effects. Fine-scale elements such as leaf litter, stones, woody debris, and small bare-ground patches strongly influenced species occurrence by providing thermal refugia, nesting substrates, and foraging opportunities. The invasive Argentine ant (Linepithema humile) exhibited strong but spatially restricted dominance and species-specific negative effects on native ants, emphasising the role of habitat context in mediating invasion impacts. Our results demonstrate that urban biodiversity is maximised by enhancing fine-scale habitat heterogeneity rather than increasing green cover alone. We highlight practical design principles for urban green infrastructure that prioritise structural diversity and ground-layer complexity to support resilient arthropod communities.

Yeasts thriving in floral nectar have a proven ecological engineering capacity, as they modify the internal environment and the rewards of individual flowers in ways that influence how plants and pollinators interact. This floricentric perpective, however, produces only a partial view of the potential role of yeasts in plant-pollinator interactions, and little is known on their possible engineering effects on whole inflorescences. This study assessed yeast ability to shape features of the vertical inflorescences of Gladiolus illyricus (Iridaceae), a Darwins syndrome plant (acropetalous protandrous flowers pollinated by insects foraging from bottom to top). When yeasts were excluded from inflorescences a declining gradient in nectar sugar concentration built up from the oldest, female-stage flowers at bottom up to the youngest, male-stage ones at top. This plant-intrinsic gradient was reversed in inflorescences with yeasts, where sugar concentration increased from the female-stage flowers harboring dense yeasts population to male-stage ones with few yeasts. The two species of yeasts involved (Metschnikowi reukaufii and M. gruessii) differed in their effects. Results add support to the growing consensus that specialized nectar yeasts can obfuscate intrinsic patterns of intra and interspecific variation in flowering features of plants at the level of individual flower, inflorescence, population and plant community.

Pollination is of key importance for tropical agriculture, yet a bee-centred perspective often overlooks the critical role of nocturnal insects in pollination services. We evaluated the relative contributions of diurnal and nocturnal pollinators to papaya yields on subsistence farms in the Taita Hills, Kenya, a globally important biodiversity hotspot. We combined flower visitor observations with five experimental treatments: open pollination, wind-only (closed), hand pollination, and temporal exclusions for day-only and night-only services. Our results reveal complete temporal niche partitioning between diurnal bees and nocturnal hawkmoths (Sphingidae). We found that diurnal and nocturnal pollinators provide additive, rather than redundant, services, contributing to papaya fruit set and weight to a similar extent. Despite these contributions, supplementary hand-pollination experiments indicated a significant yield gap (36.9% lower fruit set), suggesting substantial pollinator limitation. While landscape-scale factors had no significant effects, nocturnal pollinators responded positively to organic management, whereas diurnal visitors did not. This indicates that local habitat quality and ecological intensification are more critical for sustaining specialised pollinators than landscape composition. Our study highlights the vital role of nocturnal insects as an ecological safety net and emphasises that their conservation through local organic practices is essential for securing yield quantity and quality in tropical papaya farming systems.

Cropland abandonment is a widespread socio-ecological transition that can generate heterogeneous ecological outcomes, including opportunities for vegetation recovery as well as the accumulation of invasive alien plants (IAPs). Understanding broad-scale correlates of IAP richness in abandoned croplands is challenging because published studies differ in sampling design, spatial extent, and reporting detail. To provide an exploratory national-scale synthesis, we compiled literature-derived occurrence records of 57 IAP species reported from abandoned croplands across China and examined study-level recorded richness using generalized linear mixed models (GLMMs) with province as a random effect. Fourteen socio-economic and environmental predictors were screened for multicollinearity and standardized, and the number of Higher Education Institutions (HEIs) was included as a proxy for potential sampling-effort variation. Asteraceae accounted for 43.9% of recorded species, and more than 70% of taxa were classified as high-risk invaders (Levels 1-2). Recorded richness exhibited a pronounced southeast-northwest gradient, with higher values in economically developed coastal provinces. In the exploratory GLMM, regional GDP (IRR = 1.67, p < 0.05) and mean annual temperature (IRR = 1.49, p < 0.05) were positively associated with recorded richness, whereas other environmental, accessibility, soil, and sampling-effort variables showed no detectable associations. Model diagnostics indicated no evidence of overdispersion, zero inflation, or residual spatial autocorrelation. Given the heterogeneous nature of literature-derived data and the small number of study units, these results should be interpreted as broad-scale correlational patterns rather than causal drivers. The findings highlight regional socio-economic context and climatic conditions as key correlates of recorded IAP richness in abandoned croplands and provide an initial baseline for understanding invasion patterns in post-agricultural landscapes undergoing rapid land-use transitions..

Elevational gradients provide a framework for understanding how environmental filtering reorganises communities and interactions, but plant-pollinator interactions along temperate forest elevational gradients remain overlooked. We studied early-spring understorey communities at four forest sites spanning the foothills towards the timberline (450-1,000 m a.s.l.) in the Krkono[s]e Mountains, Czechia. Across six transects per elevation, we quantified flowering plant species richness, floral resources and traits, and video-recorded flowers, yielding 4,003 pollinator visits. We analysed elevational patterns in species richness, community composition, floral traits, and quantitative network characteristics. Visitation frequency and flowering plant and pollinator species richness peaked at intermediate elevations. The contribution of dipteran relative to hymenopteran pollinators increased towards higher elevations, principally because of non-hoverfly flies, whereas individual bee groups showed no uniform response. Floral resources and traits showed no uniform elevational responses, although total nectar sugar availability peaked at the highest site because of the dominant Vaccinium myrtillus. Most notably, both network-level specialisation and mean species-level specialisation were generally greater at the two higher elevations, whereas nestedness was lower and other network characteristics showed no consistent patterns. These findings suggest that shifts in pollinator composition and dominant floral resources potentially shaped interactions along the gradient. The increasing specialisation with elevation contrasts with the generalisation often expected under reduced partner availability and indicates that forest networks may follow elevational patterns not predicted from open habitats. Despite limited site-level replication, this study provides, to our knowledge, the first community-wide characterisation of plant-pollinator interactions along a temperate forest elevational gradient and identifies patterns requiring evaluation across replicated gradients.

While mutualistic symbioses with nitrogen-fixing bacteria enable plants to access fixed nitrogen, they also require substantial carbon investment. Under carbon limitation, such as shading, shifts in biomass allocation can decouple symbiotic investment from leaf and root growth, potentially compromising plant nitrogen status. Because shading shifts biomass allocation toward light acquisition, it could influence nitrogen fixing symbiosis in two opposing ways. If nodulation remains coupled to leaves rather than roots, nitrogen status should be maintained despite reduced root growth. Alternatively, if root growth constrains nodulation, nitrogen status should decline. We tested these hypotheses by manipulating light availability (full sunlight vs. 50% shade) and quantifying biomass allocation and symbiotic nodulation. Under shading, plants allocated proportionally more biomass to shoots than to roots and invested less biomass in root nodules. Relationships between nodulation and leaf or root biomass differed between treatments but converged with increasing plant size, although shaded plants never attained the root biomass observed in full sunlight. Leaf nitrogen concentration was maintained under shading because nodulation remained coupled to leaf investment despite reduced root allocation. These findings highlight that, under carbon limitation, maintaining leaf and nodule coupling enables plants to reduce nodule investment without compromising the nitrogen benefits of symbiosis.

Over recent decades, numerous studies have compared agricultural productivity across different management systems and environments, with increasing attention to the stability of crop yields. Yield stability is a key component of agroecosystem resilience under global change, yet it remains unclear whether some cropping systems are more stable than others. The debate over organic farming is particularly heated, as some evidence indicates that organic systems are less stable, while other evidence suggests the opposite. Here, we develop a conceptual and statistical framework for comparing crop yield stability across agricultural systems that explicitly accounts for a parametric function relating inter-annual yield standard deviation to mean yield value. Using a new global dataset of long-term field experiments spanning multiple crop species and environments, we show that the fitted functions relating yield standard deviation and mean yield value obtained for organic and conventional cropping systems share several important similarities. For both systems, the yield coefficient of variation (CV) significantly decreases with mean yield, and most of the difference in yield stability between conventional and organic systems is explained by differences in mean productivity. As a consequence, the CV of the two systems becomes similar as the difference in average efficiency narrows. Our framework reconciles apparently conflicting results in the literature and provides a more robust basis for comparing stability across cropping systems.

AimsHistorical land use has shaped plant diversity in Central Europe for centuries, and many plant communities of high conservation value have been maintained by long-term traditional management. This study assesses how changes in land use over the past century have affected plant community composition and vegetation-based ecological indicator values in the management-dependent mire community Primulo-Schoenetum ferruginei. LocationSouth-western Germany. MethodsWe conducted repeated vegetation surveys at multiple sites, comparing historical records with recent surveys spanning up to 97 years. Changes in species composition were analysed using multivariate approaches, and shifts in habitat conditions were assessed using indicator values for nutrients, temperature, light and mowing frequency. Information on historical management was compiled from original vegetation sources, while current management data were obtained from responsible conservation authorities and regional administration. ResultsFen communities showed pronounced temporal changes in species composition. Community turnover was significantly associated with shrub encroachment, mowing frequency, hay transfer and early mowing. In addition, species-based indicator values suggested increasing nutrient availability and temperature affinity of the vegetation, alongside decreasing light availability. Disturbance indicators pointed towards less frequent but more severe disturbance regimes in contemporary compared to historical vegetation. ConclusionsOur results demonstrate that management-dependent fen communities are highly sensitive to changes in land-use regimes, i.e. disturbance frequency and severity that is indicated to have significantly changed in the protected areas in this study. These findings highlight the importance of maintaining traditional land management practices when aiming to maintain biodiversity in calcareous fens.

This report presents a field assessment of wild Coffea eugenioides, the diploid maternal progenitor of cultivated Arabica coffee, in Nyungwe Forest National Park and the adjoining, isolated Cyamudongo forest fragment in south-western Rwanda. The assessment targeted trees identified as candidate mother trees (individuals bearing fruit and therefore potential seed sources): 59 such trees were georeferenced and measured for structural, phenological and reproductive traits using a structured KoBoToolbox questionnaire (reproduced in Annex 1). The work was undertaken to inform the establishment of a seed orchard for this species under the RTRP-Seed (IKI) and TREPA (GCF) projects implemented by Landscape Alliance (CIFOR & ICRAF in action). On C. eugenioides, the cherry is the fleshy fruit that contains the seed, so cherry load is a direct measure of fruit and seed output. Reproductive output across the assessed trees is low, highly variable and weakly related to tree size. The median tree carried an estimated 29 cherries in the whole canopy, 31% of trees carried 15 cherries or fewer, and the coefficient of variation in cherry load exceeded 110%. Tree size explained little of this variation (stem diameter, the single significant structural predictor, accounted for under 10% of the variance; r = 0.31). Trees in the isolated Cyamudongo fragment carried significantly fewer cherries than those in the main Nyungwe block (medians 15 vs 32 cherries; Mann-Whitney p = 0.021), and every observation of sub-optimal on-tree seed quality occurred in the fragment. Low and asynchronous fruiting, together with the reduced fruit and seed set typical of small, isolated populations, makes large-scale seed collection an unreliable basis for an orchard. The original plan was to collect seed from wild trees and raise a Breeding Seed Orchard (BSO). On the evidence presented here, that plan should be redirected toward a Clonal Seed Orchard (CSO): rather than collecting seed, scions (budwood) are taken from selected wild trees and grafted onto vigorous local Rwandan Coffea arabica rootstock. This captures the full genotype of each selected tree, shortens the time to flowering, secures the germplasm of a threatened wild relative ex situ, and aligns with Rwandas restoration and climate commitments.

Surges in food availability create localized but intense foraging opportunities, often attracting multi-species consumer groups. Agricultural practices can trigger these surges, prompting bird associations. However, the strength and duration of the association, as well as its drivers, remain unclear. This study examines waterbird association with harvesting and ploughing events in rice fields. The duration and magnitude of these associations were determined and three hypotheses addressed to explain them: (1) increased food availability, (2) enhanced foraging success and (3) reduced time allocated to vigilance. Waterbird counts and GPS tracking revealed strong associations with management events. Bird numbers spiked during events but declined within one to two days. Food availability (and soil penetrability) increased significantly during events - crayfish and rice during harvesting, worms and soil penetrability during ploughing - supporting Hypothesis 1. However, this did not improve foraging performance (intake rate, foraging success), rejecting Hypothesis 2. Higher competition, interference or kleptoparasitism in these large mixed-species flocks may offset increased food availability benefits. Alternatively, functional responses of target species may limit prey intake due to physiological or behavioural constraints. Hypothesis 3 was also unsupported, as birds did not reduce vigilance. It is plausible that birds may be drawn to events by the perception of a feast, not actual benefits. Gregariousness and foraging behaviour by local enhancement may explain such associations. Results highlight the complexity of bird responses to food surges while suggesting waterbirds in rice fields maintain stable foraging performance during agricultural management events and otherwise, indicating resilience to agricultural timing shifts.

Devils gardens are among the most striking ant-plant mutualisms in Amazonian forests. In this system, the tree Duroia hirsuta is associated with the ant Myrmelachista schumanni, which actively removes neighboring vegetation and maintains nearly monodominant patches of the host plant. Despite the apparent efficiency of this system, repeated field observations at the Tiputini Biodiversity Station, Yasuni Biosphere Reserve, revealed that individuals of Palicourea alba recurrently occur within active devils gardens. Palicourea alba closely resembles dead plant material, exhibiting leaf morphology and coloration that strongly mimic the surrounding litter layer, and appears to be uncommon outside these gardens. To our knowledge, this "dead-leaf" masquerade has not been previously documented in this intensively studied system, making it a particularly striking and unexpected observation. To evaluate whether this masquerade facilitates persistence within devils gardens, we surveyed 35 gardens and recorded P. alba in 19 (52.8%). When present, P. alba covered on average 27% of plot area, while mean herbivory across sampled leaves remained low (8.6%). Generalized linear mixed models showed that P. alba cover decreased significantly with increasing herbivory (F = 8.09, p = 0.0159), whereas herbivory increased with leaf-litter cover (F = 8.73, p = 0.0120). Field observations further revealed that many individuals are nearly indistinguishable from dry leaf litter, suggesting a role for visual crypsis or masquerade. Together, these results indicate initially, that the persistence of P. alba within devils gardens is mediated by a multi-layered ecological filtering process. First, masquerade likely reduces detection by M. schumanni, allowing seedlings to escape ant-mediated removal. Second, low herbivory suggests either enemy avoidance or reduced apparency to herbivores within the simplified understory. Third, spatial heterogeneity in leaf-litter cover may create microhabitats where both ant activity and herbivore pressure are modulated, reinforcing establishment success. This system thus represents a previously undocumented mechanism in which plant-litter resemblance enables persistence within a highly structured, biotically filtered habitat, highlighting how subtle trait-mediated interactions may modulate outcomes in otherwise strongly deterministic mutualisms.

Grasslands are vulnerable to increasing drought with global warming, but process-based models lack the mechanistic knowledge required to predict the magnitude of drought impacts. While a plant hydraulics framework has been successful in advancing process understanding of drought responses in trees, and how drought responses vary across rainfall gradients, similar approaches have rarely been applied to grasses. Here, we quantified the progression of key drought response processes in sixteen dominant perennial grasses (seven C3 and nine C4) with differing climatic origins across eastern Australia. We found that stomatal closure, hydraulic impairment and leaf browning occurred concurrently, in contrast to the progressive sequence typically observed in trees. We also found that drought response traits were not correlated with species climate of origin. The early impairment of leaf hydraulic conductance and leaf browning along with the lack of correlation with climate of origin suggest that grasses may employ fundamentally different strategies to adapt to low water availability than trees. These results highlight the need for grass-specific parameterization of drought responses in process-based models.

Understanding the relationships between soil macrofauna and decomposition is crucial for predicting how land-use change impacts ecosystem function in fragmented systems. This is because soil macrofauna affect decomposition and also respond to the changes in abiotic conditions across habitat gradients. This study investigates edge effects on the macrofauna contributions to decomposition across forest-field ecotones. We used bait lamina assay to quantify aboveground and belowground feeding activity of soil macrofauna in Autumn 2025 in three deciduous forest-old field ecotones and one coniferous forest-old field ecotone, in Southwestern Ontario, Canada. Vegetation diversity and composition, LAI and soil characteristics (i.e., soil organic matter, pH, temperature and moisture) were measured at each plot along the ecotone. Pitfall trap data collected in Summer 2025 at the same sites were used to characterize macrofauna communities. We used generalized linear mixed effects models to estimate the effect of distance to edge, site, and depth into the soil on bait lamina consumption and soil macrofauna, with transect nested within site as random effects. Consumption activity increased with distance into the forest from the field, with the edge representing an intermediate; and, decreased with increasing depth into the soil. In contrast, soil macrofauna abundance, especially isopods, decrease with distance into the forest from the field. These trends varied significantly across sites, so that consumption activity and abundance sometimes remained constant across the ecotone (i.e., site x distance interaction). The results demonstrate that macrofaunal contributions to bait consumption varied along the ecotone, shaped by interacting environmental gradients and shifts in community composition unique to each site.

1. Ruby-throated hummingbirds (Archilochus colubris) exhibit flower preferences and readily visit human subsidies like feeders. However, foraging behavior and plant-animal interactions may vary across spatial, temporal, and landscape gradients. Despite the popularity and ubiquity of Ruby-throated Hummingbirds in the eastern U.S., there has never been a quantitative assessment of their flower preferences or feeder use across broad scales. 2. We investigated how feeder visitation, flower visitation, and flower trait preferences vary by latitude, season, and land use in the northeastern United States using over 6 million occurrence records of Ruby-throated Hummingbirds and flowering plants, >2,100 annotated hummingbird-flower interactions, and >2,700 feeder visit occurrences. 3. We found that hummingbird feeder use declined over the year, increased with latitude, and was higher in developed landscapes. Flower visitation increased over the year across all latitudes, with higher visitation in developed landscapes. Finally, we found that native plant use diverged between landscapes, such that the probability of visiting a native flower increased over time in non-developed land uses but declined over time in developed ones, demonstrating that hummingbirds track the advancement of native floral phenology and use non-native, cultivated flowers as a human subsidy due to either availability or preferences. 4. Our preference and network models revealed that while hummingbird-plant network structure was similar across landscapes, the composition of important taxa shifted from native, wild species like Monarda and Impatiens to non-native, cultivated species like Salvia. 5. Using trait-based models of flower visitation, we found that hummingbirds preferred native, tubular, and red/orange flowers fitting the hummingbird pollination syndrome despite visiting >260 different plant species. Red and orange flowers were preferred across all seasons, suggesting color may be a reliable signal of nectar availability across species and contexts. Native and tubular flowers were strongly preferred during the breeding season; however, preferences relaxed during spring and fall migration. 6. These findings reveal the consistent preferences of Ruby-throated Hummingbirds for native, tubular, and red/orange flowers, and underscore how spatial and temporal factors reshape foraging behavior and trait preferences. Our results also highlight the value of community-collected data in characterizing plant-pollinator interactions across broad spatial and temporal scales.