Find research datasets worth reusing

Search datasets from major research repositories and use ShareScore to quickly assess how well each record supports discovery, access, and reuse.

datasets available to search

ShareScore release 0.9.0

Dataset results

56 results for “Seed disperser effectiveness”

Learn how ShareScore rates datasets ↗

dryad32/100

Data from: Pre-dispersal seed predators and fungi differ in their effect on Luehea seemannii capsule development, seed germination and dormancy across two Panamanian forests

Pre-dispersal seed predation can greatly reduce crop size affecting recruitment success. Additionally, non-fatal damage by seed predators may allow infection by fungi responsible for post-dispersal seed losses. The objectives of this study were (1) to quantify pre-dispersal seed predation and fungal infection in a Neotropical tree species, Luehea seemannii, that produces dehiscent fruits and wind-dispersed seeds, and (2) to link pre-dispersal effects on seed quality to seed survival in the soil. To examine how seed predators and fungi influence seed losses, mesh exclosures, fungicide and the combination of both treatments were applied to separate branches in the canopy of trees in Gamboa and Parque Natural Metropolitano (PNM), Panama. To determine if treatments affect seed viability and survival in the soil, half of the seeds collected from each treatment were buried for four weeks in forest soils and subsequently allowed to germinate before and after the breaking of dormancy. Overall, 24 percent of developing fruit were lost to insect attack. In contrast, fungi infected only 3 percent of seeds at the pre-dispersal stage. For seeds germinated directly after collection, fungicide significantly increased germination in the wetter site (Gamboa) but decreased germination in the drier site (PNM). The pre-dispersal insect exclosure treatment increased the fraction of seeds that remained dormant after burial in the soil. This result suggests that exposure to insect predators may cause physical damage to seeds that results in the loss of physical dormancy but does not necessarily increase the susceptibility of seeds to pathogen attack in the soil.

opencc-zeroDec 2016View details →

dryad32/100

Data from: Divergent effects of forest edges on host distribution and seed disperser activity influence mistletoe distribution and recruitment

1. Species interactions define functional diversity and community stability across ecosystems, and depend on the spatial distribution, the habitat requirements, and the sensitivity to disturbances of all interacting partners. Hence, assessing the effects of such anthropogenic disturbances on multi-species interactions may be essential to improve adaptation and mitigation measures for biodiversity conservation. 2. We determined the importance of edge effects on the interaction and distribution of three keystone species in South American temperate rainforests: the hemiparasitic mistletoe Tristerix corymbosus, its main host (the liana Campsidium valdivianum) and its only seed disperser (the marsupial Dromiciops gliroides). 3. The discordant impacts of forest edges on host (positive) and seed disperser (negative) affected mistletoe distribution at large spatial scales, owing to the combined effects of increased dispersal limitation and decreased host availability. More importantly, marsupial abundance had contrasting effects on mistletoe abundance at small and large spatial scales – suggesting a potential trade-off between local and long-distance dispersal. 4. We found the number of adult mistletoes per host increased with host size, which likely indicates that mistletoe colonization accumulated over the host's life-span. However, the number of juveniles found per host peaked at medium-sized hosts, increased with marsupial abundance and host availability and showed a negligible response to edges. 5. Synthesis: The lack of spatial congruence between host and seed disperser probably explains the scarcity of mistletoes in the study area, although the discordant drivers of juvenile and adult distributions suggest that there is a trade-off between recruitment patterns but also potential dispersal limitation at small scales. In essence, the interdependence among species linked by (mutualistic and antagonistic) interactions makes them more sensitive to anthropogenic disturbance, exacerbating its impact on the diversity and functioning of forest ecosystems.

opencc-zeroDec 2014View details →

dryad32/100

Data from: Large frugivores matter: insights from network and seed dispersal effectiveness approaches

1.While large avian frugivores are known to be key dispersers for large‐seeded tree species, their role in community‐wide plant‐disperser networks is still poorly known. Large avian frugivores are also among the most threatened due to anthropogenic impacts. 2.We evaluated the role of large avian frugivores in a plant‐disperser community by a) determining whether the plant‐disperser community was modular, with a distinct community of large frugivores (thereby highlighting their importance), b) determining relative qualitative and quantitative roles played by large‐bodied frugivores vis‐à‐vis other frugivores and c) determining impacts of large‐bodied frugivore loss on the plant‐disperser community. 3.The study was carried at a tropical forest site in north‐east India which is part of the Eastern Himalaya Biodiversity Hotspot. We collected tree watch data (2055 h) from 46 tree species, which represented 85% of tree species that are predominantly bird‐dispersed in the area. 4.We found that the plant‐disperser community was modular, with a distinct module of large‐seeded tree species and large frugivores. Intermediate‐sized frugivores such as barbets and bulbuls were the most connected, while large‐sized frugivores, such as hornbills and imperial‐pigeons were moderately well‐connected. Qualitative and quantitative roles played by different dispersers varied across the gradient of frugivore body size. Hornbills, the largest avian frugivores, consumed a significantly greater number of fruits and swallowed larger proportions of fruits compared to other avian groups. In comparison to similar‐sized frugivores, imperial‐pigeons fed on larger‐sized fruits, highlighting their importance for dispersal of large‐seeded plants. Under simulated extinction scenarios, larger extinction cascades weren't necessarily caused by larger frugivores, however, extinctions of certain large‐bodied frugivores (hornbills, imperial‐pigeons) caused extinction cascades. 5.Integrating information from networks and seed dispersal effectiveness approaches enabled a better understanding of large frugivore role in a plant‐disperser community. While large‐bodied frugivores may not be playing a central role in plant‐disperser communities, they are crucial as seed dispersal service providers for large‐seeded plants. In conjunction with the reported local extinctions of large frugivores like hornbills from the south Asian region, this study's findings highlight the irreplaceable quantitative and qualitative impacts that tropical plant communities are likely to experience in the future.

opencc-zeroDec 2018View details →

dryad32/100

Persistence of seed dispersal in agroecosystems: effects of landscape modification and intensive soil management practices in avian frugivores, frugivory and seed deposition in olive croplands

Farming impacts on animal-mediated seed dispersal through mechanisms operating at least at two spatial scales: first, at the landscape scale, through habitat loss and land conversion to agriculture/livestock grazing, and second, by local intensification (farm scale) of the agricultural practices. Nonetheless, these two scales of farming impact on the seed dispersal function have been rarely integrated. In particular, studies evaluating the effect of agriculture in the seed dispersal function of frugivorous birds in Mediterranean ecosystems are lacking. We evaluate the role of the landscape transformation, from fruit-rich woodland habitats to olive grove landscapes, together with the local intensive practices of soil management on the persistence of the seed dispersal function for Mediterranean fleshy-fruited plants in olive landscapes of south Spain. We used bird censuses, mist-nets and seed traps to characterize avian frugivore assemblages, frugivory, and seed deposition in seminatural woodland habitat (SNWH) patches and olive fields of 40 olives farms of 20 localities distributed across the whole range of olive cultivation in Andalusia (southern Spain). We found that despite of a still remarkable dispersal function in olive grove landscapes, avian frugivore abundance and diversity, frugivory, and seed arrival decreased in olive fields compared to SNWH patches. Likewise, SNWH cover loss and/or olive growing expansion decreased avian frugivory and seed arrival. Interestingly, habitat effects in the olive farms often depended on the landscape context. In particular, less diverse fruit-eating bird assemblages pooled in SNWH patches as olive grove cover increased or SNWH decreased in the landscape, while remained relatively invariant in the olive fields. Finally, compared to conventional intensive agriculture, low-intensity management increased frugivory and seed deposition. We conclude that olive fields are less permeable to frugivores than expected by its agroforest-like nature, and that presence of SNWH patches is crucial for the maintenance of frugivory and seed dispersal in agricultural landscapes. Results evidence that woodland habitat loss by olive expansion and the intensive practices seriously threaten the dispersal service in olive-dominated landscapes. Maintenance, restoration and promotion of woodland patches should be prioritized for the conservation of the seed dispersal service and for enhancing the functional connectivity in human-shaped olive landscapes.

opencc-zeroNov 2021View details →

dryad32/100

Ecology of fear and its effect on seed dispersal by a neotropical rodent by Dumas Gálvez and Marisol Hernández

Predators exert negative effects on prey, besides the act of killing, generating behavioral and physiological costs, a concept known as the ecology of fear. Studies in scatterhoarding rodents in temperate zones suggests that prey use habitat structure to perceive predation risk. Less is known about how tropical forest rodents perceive predation risk. Here, we investigated whether the Central American agouti perceive predation risk by ocelots through olfactory cues and whether it influences the foraging behavior for Attalea butyracea seeds, one of its main food sources. By monitoring tagged seeds, we found that seed dispersal and pilferage was lower in sites with high density of ocelots, in line with the predictions of ecology of fear proposing that scared animals eat less. We also found that pilferage rates in high ocelot density sites seem to be lower during the rainy - transition period but not during dry season when food availability is generally low. However, we did not find evidence that agoutis adjust their cache spacing behavior in response to ocelot density. In an additional experiment to corroborate that agoutis' responses were caused by ocelots' cues, we found lower dispersal rates for seeds placed next to samples of urine and feces of ocelots as compared to controls, during the first seven days. Moreover, agoutis spent less time handling the seeds with ocelots' cues. Here, we discuss potential cascading effects linked to the behavior of agoutis towards predation risk.

opencc-zeroJan 2022View details →

zenodo32/100

Fig. 3 in Seed dispersal effectiveness: A comparison of four bird species feeding on seeds of invasive Acacia cyclops in South Africa

Fig. 3. Geographic distribution (i.e. green colour) of the studied bird species in Southern Africa, namely, the frugivorous (a) Knysna turaco Tauraco corythaix, and (b) the red-winged starling Onychognathus morio, (c) the granivorous red-eyed dove Streptopelia semitorquata, and (d) the laughing dove S.senegalensis (SABAP 2 http://www.adu.org.za/ accessed 23 June 2015).

opennotspecifiedJul 2016View details →

zenodo32/100

Fig. 2 in Seed dispersal effectiveness: A comparison of four bird species feeding on seeds of invasive Acacia cyclops in South Africa

Fig. 2. Seed dispersal effectiveness (i.e. a product of germination rates (quality) and average adult body mass as proxy for seed load (quantity) for different bird species that ingested seeds of Acacia cyclops: the frugivorous Knysna turaco Tauraco corythaix, and the red-winged starling Onychognathus morio, the granivorous red-eyed dove Streptopelia semitorquata, and the laughing dove S. senegalensis. Different letters above the bars show statistically significant difference. Error bars show standard error of mean.

opennotspecifiedJul 2016View details →

zenodo32/100

Fig. 1 in Seed dispersal effectiveness: A comparison of four bird species feeding on seeds of invasive Acacia cyclops in South Africa

Fig. 1. Seed dispersal quality (i.e. mean germination rates % ± SE) for untreated (experimental control) and gut-passed Acacia cyclops seeds through different bird species:the frugivorous Knysna turaco Tauraco corythaix, and the red-winged starling Onychognathus morio, the granivorous red-eyed dove Streptopelia semitorquata, and the laughing dove S. senegalensis. Different letters above the bars show statistically significant difference. Error bars show standard error of mean.

opennotspecifiedJul 2016View details →

zenodo32/100

Species and plot characteristics for River restoration effects on dispersal and the development of riparian seed bank: Do poor seed banks limit restoration of boreal riparian zones?

Vegetation composition in boreal streams in the standing vegetation and the seed bank,

opencc-by-4.0Nov 2024View details →

dryad32/100

Frugivory and seed dispersal in the Cerrado: Network structure and defaunation effects

Seed dispersal is a fundamental process that is highly threatened by the rapid decline of large-bodied frugivores worldwide. The Brazilian Cerrado, the largest savanna in the world, represents an ideal site for investigating seed dispersal because of its biodiversity, environmental challenges, and knowledge shortfalls. We performed a Systematic Literature Review to analyze the seed dispersal network in the Cerrado and the potential impacts of the defaunation of large-bodied frugivores on it. We considered network metrics, calculated the defaunation index of the frugivore assemblage, and compared traits among different fruit-sized plants and their respective dispersers in the network. We retrieved 1,565 interactions involving 193 plant species and 270 animal species. Results show that the Cerrado seed dispersal network is slightly nested and considerably modular, dominated by small to medium-sized generalist species, such as passerines, marsupials, and mesocarnivores. Nonetheless, large-bodied frugivores like the lowland tapir have a key role in the network due to their great foraging and network integration capacity. The Cerrado frugivore assemblage is moderately defaunated, with possible effects in its interactions with large-fruited plants. The Cerrado's defaunation and functional loss of large vertebrates deserve urgent attention to further understand the impacts on seed dispersal mechanisms and ecosystem functioning.

opencc-zeroMay 2023View details →

dryad32/100