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The consequences of plant–animal interactions often transcend the mere encounter stage, as those encounters are followed by a chain of subsequent stages on the plant's reproductive cycle that ultimately determine fitness. Yet, the dissemination and recruitment stages of animal-mediated seed dispersal are seldom analysed jointly, hindering a full understanding of the ecology of seed dispersal. We analyse the dispersal and recruitment of a fleshy-fruited plant (Pistacia lentiscus), from fruit production to seedling survival up to their second year. We link early reproductive investment of individual plants to seedling recruitment and explore the role played by seed viability, the coterie of frugivores and microhabitat seed deposition. The proportion of viable seeds was generally low (mean = 34%) but highly variable among individual plants (range: 0%–95%). Seed viability did not seem to have a direct effect on individual plant's recruitment. We recorded 28 bird species feeding on P. lentiscus fruits or seeds. Their contribution to plant recruitment was mainly determined by their intensity of fruit consumption and probability to disperse viable seeds. Most frugivores presented non-random microhabitat preferences, delivering uneven seed contributions to different sites. Post-dispersal seed predation by rodents was the most limiting phase in P. lentiscus recruitment. Yet, microhabitats showing the lowest predation rates received the lowest seed rain. Hence, we found a decoupling of the dissemination and recruitment stages: most seeds do not arrive at the most suitable microhabitats. We estimate P. lentiscus plants need to produce c. 5 × 105 fruits to recruit a single seedling that survives to its second summer in our study site. Its success as a prevalent species in Mediterranean lowland landscapes relies on its high fecundity and thorough fruit removal and dispersal by a diversified frugivore assemblage, which compensates for the high seed unviability characteristic of t

[EN] Studying interactions among species and their multiple forms and outcomes has become a central question of ecological research. Mutualisms have changed the way ecologists understand the functioning of ecosystems. Generalised mutualistic networks, especially among free-living species, have been observed to include highly heterogeneous assemblages, in which most species establish few interactions while a minority of species establish a wide range of interactions. These highly connected species are referred to as super-generalists. They are characterised for connecting otherwise isolated groups of interacting species or modules and for providing stronger cohesion to ecological networks. Their characteristics make them fundamental for local biodiversity and the structure and stability of interactions. In this PhD thesis we aim to better comprehend the super-generalist strategy and the mutualistic interactions at the individual level. For this purpose, we use as a model organism Pistacia lentiscus L. (Anacardiaceae), a woody shrub species abundant in the Mediterranean Basin, together with the coterie of frugivorous animals that consume its fruits and disperse its seeds. In Chapter 1 we review sampling methods used to record frugivory interactions, assessing their strengths, caveats, and convenience in different contexts. We discuss different approaches for combining data gathered using different methodologies. In Chapter 2, we explore the effectiveness of the frugivory/seed-dispersal mutualism between individual plants of P. lentiscus and its avian frugivore assemblage, assessing the level of reciprocity in reward exchange and dependence asymmetry among partners. In Chapter 3 we investigate the delayed outcomes of animals’ fruit consumption in early seedling recruitment of P. lentiscus plants. Lastly, in Chapter 4 we analyse individual-based networks of different plant species and regions of the world, we compare their topology and structure with that of species-bas, [ES] Estudiar las interacciones entre especies junto a sus múltiples formas y resultados se ha convertido en una cuestión central de la investigación en ecología. Los mutualismos han cambiado la forma en que los ecólogos entienden el funcionamiento de los ecosistemas. Se ha observado que las redes mutualistas generalizadas, especialmente entre especies de vida libre, incluyen conjuntos muy heterogéneos, en los que la mayoría de las especies establecen pocas interacciones, mientras que una minoría de especies establece una amplia variedad de interacciones. Estas especies altamente conectadas se denominan super-generalistas. Se caracterizan por conectar grupos de especies o módulos que de otro modo estarían aislados, y por proporcionar una mayor cohesión a las redes ecológicas. Sus características las convierten en especies fundamentales para la biodiversidad local así como para la estructura y estabilidad de las interacciones. En esta tesis doctoral pretendemos comprender mejor la estrategia supergeneralista y las interacciones mutualistas a nivel individual. Para ello, utilizamos como organismo modelo Pistacia lentiscus L. (Anacardiaceae), una especie arbustiva leñosa abundantemente distribuida por la cuenca mediterránea, junto a los animales frugívoros que consumen sus frutos y dispersan sus semillas. En el Capítulo 1 se revisan los métodos de muestreo utilizados para registrar las interacciones de frugivoría, evaluando sus ventajas, inconvenientes y conveniencia en diferentes contextos; y se discuten diferentes enfoques para combinar los datos recogidos utilizando diferentes metodologías. En el Capítulo 2, exploramos la eficacia en el mutualismo frugivoría/semilla-dispersión entre plantas individuales de P. lentiscus y las aves frugívoras que consumen sus frutos, evaluando el nivel de reciprocidad en el intercambio de recompensas y la asimetría de dependencia entre los socios. En el Capítulo 3, investigamos los resultados aplazados del consumo de frutos por animal

The goal of this repository is to contain and facilitate access to the data associated to the datapaper FRUGIVORY CAMTRAPS: A dataset of plant-animal interactions recorded with camera traps, Ecological interactions are a key component of biodiversity, essential for understanding ecosystem services and functioning. Recording and quantifying ecological interactions is challenging, frequently requiring complex logistics and substantial effort in the field. Camera traps are routinely used in ecology for various applications and have proven to be an excellent method for passive and non-invasive sampling of plant-animal interactions. We implemented a standardized camera trap protocol to monitor frugivory interactions between fleshy-fruited plant species and vertebrate frugivores in Doñana National Park, SW Spain. The central objective was to inventory the diversity of plant-animal ecological interactions providing seed dispersal services. We recorded pairwise interactions between plant individuals and vertebrate frugivore species from 2018 to 2023, reporting both qualitative information (presence-absence of the interaction) and quantitative data (frequency of visits). Each record in the dataset contains information of a visit by an individual animal to an individual plant, resulting in any form of fleshy-fruit use and provides information on visitation phenology, visit length and feeding behavior. The dataset presented here includes 10,659 frugivory interactions for 59 vertebrate species (46 birds, 13 mammals) recorded on 339 plant individuals from 13 different plant species which dominate the fleshy-fruited plant assemblage in the Doñana National Park. The most recorded animal species consuming fruits and playing a legitimate seed dispersal role was Curruca melanocephala (1678 records) among birds and Vulpes vulpes among mammals (751 records). On the other hand, Cervus elaphus was the most recorded mammal species (1508 records), but it is a fruit consumer with a marginal role as legitimate seed disperser. Avian frugivores, particularly those from the Sylviidae and Turdidae families, are widespread in the region, and play a crucial role in maintaining the dis

Protocol and tools for processing large numbers of video-recorded files generated during camera trap surveys for behavioral monitoring (i.e. plant-animal interactions, visits of animal frugivores to fruiting plants).

Mutualistic interactions among free-living species generally involve low-frequency interactions and highly asymmetric dependence among partners, yet our understanding of factors behind their emergence is still limited. Using individual-based interactions of a super-generalist fleshy-fruited plant with its frugivore assemblage, we estimated the Resource Provisioning Effectiveness (RPE) and Seed Dispersal Effectiveness (SDE) to assess the balance in the exchange of resources. Plants were highly dependent on a few frugivore species, while frugivores interacted with most individual plants, resulting in strong asymmetries of mutual dependence. Interaction effectiveness was mainly driven by interaction frequency. Despite highly asymmetric dependences, the strong reliance on quantity of fruit consumed determined high reciprocity in rewards between partners (i.e. higher energy provided by the plant, more seedlings recruited), which was not obscured by minor variations in the quality of animal or plant service. We anticipate reciprocity will emerge in low-intimacy mutualisms where the mutualistic outcome largely relies upon interaction frequency.

Seed dispersal by frugivorous bird species involves a fine temporal tuning between fruiting plants and birds. However, this interaction may be severely threatened by anthropogenic climate and land-use change, which may result in phenological mismatches and pervasive ecological consequences for avian communities. In this study, we evaluate changes at long (~40 years) and short-time (seasonal) spans in an avian frugivore community using a snapshot resampling. Particularly, we focus on changes in composition, abundance, migratory timing (i.e., phenology), and physical condition in relation to variations in fruit supply. We used bird and fruit data collected during 1981-1983 and 2019-2021 in a Mediterranean scrubland site in Doñana Natural Area, SW Spain. Our findings indicate a profound transformation of species composition, bird phenology, and body condition: in ~40 years, the avian community showed a 66% and 13% decrease of the wintering and seed-disperser species, respectively. Seasonal abundance peaks were advanced for at least one month in 9 out of 11 frugivorous bird species included in the analyses. Avian body condition during the migratory passage has worsened, with fewer individuals showing a high-fat percentage now than in the past. Finally, we report a fruit production decrease of almost half in 2019-2021 compared to 1981-1983, probably linked to habitat encroachment by pine trees and replacement of fleshy-fruited shrubs. Vegetation encroachment and climate change are the most plausible explanations for the observed changes in the avian community, but the relative importance of these factors is yet unknown. Our results at a local scale mirror the dramatic consequences of global change affecting the diversity, phenology, and physical condition of frugivorous bird species reported in multiple studies across the globe. The loss of frugivores may trigger feedback mechanisms in which seed dispersal is disrupted, leading to impaired recruitment of fruiting plants

Recording species interactions is one of the main challenges in ecological studies. Frugivory has received much attention for decades as a model for mutualisms among free-living species, and a variety of methods have been designed and developed for sampling and monitoring plant–frugivore interactions. The diversity of techniques poses an important challenge when comparing, combining or replicating results from different sources with different methodologies. With the emergence of modern techniques, such as molecular analysis or multimedia remote recorders, issues when combining data from different sources have become especially relevant. We provide an overview of all the techniques used for monitoring endozoochorous primary seed dispersal, focusing on a critical appraisal of the advantages and limitations, as well as the context-dependency nature, of the different methods. We propose five data merging approaches potentially useful to combine frugivory interactions data from different methodologies. Additionally, we provide two case studies where we combine empirical data from plant–animal interactions in Mediterranean shrublands using different methodologies. Data merging resulted in a net increase in the number of distinct pairwise interactions recorded and compensated biases inherent to different methods, resulting in a more robust estimation of network topological descriptors. These case studies clarify the context-dependent character of the merging approaches, highlighting the value of collecting detailed information on the sampling effort in terms of reliable results and reproducibility. Finally, we discuss the trends with different methodological approaches used in the last decades and future perspectives in this field.

Ecological interactions are one of the main forces that sustain Earth’s biodiversity. A major challenge for studies of ecology and evolution is to determine how these interactions affect the fitness of species when we expand from studying isolated, pairwise interactions to include networks of interacting species1,2,3,4. In networks, chains of effects caused by a range of species have an indirect effect on other species they do not interact with directly, potentially affecting the fitness outcomes of a variety of ecological interactions (such as mutualism)5,6,7. Here we apply analytical techniques and numerical simulations to 186 empirical mutualistic networks and show how both direct and indirect effects alter the fitness of species coevolving in these networks. Although the fitness of species usually increased with the number of mutualistic partners, most of the fitness variation across species was driven by indirect effects. We found that these indirect effects prevent coevolving species from adapting to their mutualistic partners and to other sources of selection pressure in the environment, thereby decreasing their fitness. Such decreases are distributed in a predictable way within networks: peripheral species receive more indirect effects and experience higher reductions in fitness than central species. This topological effect was also evident when we analysed an empirical study of an invasion of pollination networks by honeybees. As honeybees became integrated as a central species within networks, they increased the contribution of indirect effects on several other species, reducing their fitness. Our study shows how and why indirect effects can govern the adaptive landscape of species-rich mutualistic assemblages.