Frugivorous animals play crucial roles dispersing seeds away from parental plants and influencing... more Frugivorous animals play crucial roles dispersing seeds away from parental plants and influencing plant recruitment. Most studies focus on comparisons of seed dispersal services provided by distinct species of animals, but neglect how within‐species variation may affect dispersal. Individual traits, such as body mass and sex, are related to metabolic rates, gut load capacity, and transit times that potentially influence dispersal quantity and quality. Here, we aim at answering if individual traits (body mass and sex) of Pale‐breasted Thrushes (Turdus leucomelas) affect seed dispersal quality by testing the following hypotheses (a) individual traits influence seed retention time and germination, (b) seed retention time affects seed germination, and (c) seed passage through the gut enhances germination. We found that females retained seeds in the gut for longer periods than males. Gut passed and manually depulped seeds had similar germination success. However, heavier birds, irrespect...
Results obtained from other classifications of bird sensitivity to human disturbances, based on S... more Results obtained from other classifications of bird sensitivity to human disturbances, based on Stotz et al. 1996.
# MS_Carbon<br> Supplemental information, code, and data for the MS: <br> Carolina Be... more # MS_Carbon<br> Supplemental information, code, and data for the MS: <br> Carolina Bello, Mauro Galetti, Marco A. Pizo, Luiz Fernando S. Magnago, Mariana Ferreira Rocha, Renato A. F. Lima, Carlos A. Peres, Otso Ovaskainen, and Pedro Jordano (2015). Defaunation impacts carbon storage in tropical forests. *Summary*:<br> Carbon storage is widely acknowledged as one of the most valuable forest ecosystem services. Deforestation, logging, fragmentation and climate change have significant impacts on tropical carbon stocks, however an elusive and yet undetected decrease in carbon storage may be due to defaunation of large seed dispersers. Many large tropical trees with sizeable contributions to carbon stock rely on large vertebrates for seed dispersal and regeneration, yet many of these frugivores are threatened by hunting, illegal trade and habitat loss. We used a large dataset on tree species composition and abundance, seed, fruit and carbon related traits, and plant-animal interactions to estimate the loss of carbon storage capacity of tropical forests in defaunated scenarios. By simulating the local extinction of trees that depend on large frugivores at 31 Atlantic Forest communities, we found that defaunation has the potential to significantly erode carbon storage even when only a small proportion (10%) of large-seeded trees are extirpated.
This chapter investigates which birds eat fruits and disperse seeds in degraded areas of two Braz... more This chapter investigates which birds eat fruits and disperse seeds in degraded areas of two Brazilian global biodiversity hotspots that have suffered intense and ongoing degradation (Atlantic Forest and the Cerrado). Focus is given on quantitative assessment of two aspects of avian frugivory, i.e. number of visits and fruits removed from fruiting plants. Aside from the taxonomic composition of this particular group of birds, some of the morphological (body mass, gape width) and behavioural traits (migratory status) that may influence their role as seed dispersers are reported. The idiosyncrasies of avian frugivory and seed dispersal in Brazilian degraded lands that are, in many aspects, likely to be similar to other disturbed areas around the world are emphasized based on comparisons with well-preserved areas.
The intensification of land‐use changes in tropical forests during the 20th century, mainly cause... more The intensification of land‐use changes in tropical forests during the 20th century, mainly caused by deforestation for agricultural uses, had an overwhelming influence on bird assemblages. However, how these historical anthropogenic changes have impacted the habitat use and diet of tropical birds is poorly known. Stable isotope analysis (δ13C and δ15N) can be useful in this regard since it provides information not only on the habitat and food resource use but also insights on the dietary niche of species. Here, we aimed to evaluate whether centenary anthropogenic impacts, mainly caused by changes in landscape composition, have affected the resource and habitat use and isotopic niche width of Neotropical birds in a region that comprises two biodiversity hotspots – the Atlantic Forest and Cerrado in southeastern Brazil. We found that the niche width of all bird guilds (frugivore, granivore, insectivore, nectarivore and omnivore) was largely reduced (28–70%) from the 20th century until recently. This niche width reduction was likely associated with historical anthropogenic impacts (e.g. fragmentation, forest loss and change in agricultural practices), which are responsible for the decrease in the availability of habitat and food resources. Moreover, the mean values of δ15N decreased over the years in all bird guilds, which might be attributed to the expansion of agricultural areas and the increase in the use of synthetic nitrogen‐based fertilizers. All the analyzed species, even though some of them are diet and habitat generalists, were strongly influenced by centenary anthropogenic actions. Our results show the consequences of human‐induced changes in land use on the diet and habitat use of tropical birds that persist in fragmented landscapes, which might compromise their long‐term survival and provide useful information to the conservation strategies of bird assemblages in modern landscapes.
Seed dispersal by vertebrates is fundamental for the persistence of plant species, forming networ... more Seed dispersal by vertebrates is fundamental for the persistence of plant species, forming networks of interactions that are often nested and modular. Networks involving angiosperms and frugivorous birds are relatively well‐studied in the Neotropical region, but there are no previous studies of networks involving waterbirds. Here, we describe the structure of a Neotropical waterfowl seed‐dispersal network and identify the species that have an important role for the network structure. We used information on 40 plant taxa found in fecal samples of five common waterfowl species to calculate the nestedness (NODF), weighted nestedness (WNODF), modularity, and weighted modularity of the network. We found that the network was nested, with yellow‐billed teal showing the highest contribution both to nestedness and weighted nestedness. Twenty‐four plant species contributed positively to weighted nestedness, with Salzmann's mille graines presenting the highest influence both to nestedness and weighted nestedness. The network was modular, but the weighted modularity was not significant. These results need to be considered with caution due to incomplete interaction sampling for two species. Ringed teal, Brazilian teal, and yellow‐billed teal were considered hub modular species. Among plants, beak sedges and water snowflake were considered modular hub species, while Salzmann's mille graines and spikerush were network connectors. The structure of this Neotropical waterbird seed‐dispersal network differed from the only previous waterfowl network study, from Europe, which found similar level of nestedness but no significant modularity. We include several possible explanations for this discrepancy and identified priorities for future research into waterbird–plant interaction networks.Abstract in Portuguese is available with online material.
The Atlantic Forest is the second largest tropical moist forest domain in South America after the... more The Atlantic Forest is the second largest tropical moist forest domain in South America after the Amazon, home to over 800 bird species (223 endemics or 27% of the avifauna). With only 28% of the original vegetation left, mostly fragmented and altered, the Atlantic Forest is a hotspot for bird conservation. We first introduce the extent, vegetation types, and exploitation history of the domain, and the composition and biogeographic affinities of its birds. We then provide an overview of the knowledge gathered so far on the ways Atlantic Forest birds thrive in the often-fragmented landscape, highlighting the landscape features that influence their occurrence and movement behavior. We end with the conservation issues affecting the Atlantic Forest birds and the actions hitherto taken to address them, including the establishment of conservation units, forest restoration, and rewilding.
Frugivorous animals play crucial roles dispersing seeds away from parental plants and influencing... more Frugivorous animals play crucial roles dispersing seeds away from parental plants and influencing plant recruitment. Most studies focus on comparisons of seed dispersal services provided by distinct species of animals, but neglect how within‐species variation may affect dispersal. Individual traits, such as body mass and sex, are related to metabolic rates, gut load capacity, and transit times that potentially influence dispersal quantity and quality. Here, we aim at answering if individual traits (body mass and sex) of Pale‐breasted Thrushes (Turdus leucomelas) affect seed dispersal quality by testing the following hypotheses (a) individual traits influence seed retention time and germination, (b) seed retention time affects seed germination, and (c) seed passage through the gut enhances germination. We found that females retained seeds in the gut for longer periods than males. Gut passed and manually depulped seeds had similar germination success. However, heavier birds, irrespect...
Results obtained from other classifications of bird sensitivity to human disturbances, based on S... more Results obtained from other classifications of bird sensitivity to human disturbances, based on Stotz et al. 1996.
# MS_Carbon<br> Supplemental information, code, and data for the MS: <br> Carolina Be... more # MS_Carbon<br> Supplemental information, code, and data for the MS: <br> Carolina Bello, Mauro Galetti, Marco A. Pizo, Luiz Fernando S. Magnago, Mariana Ferreira Rocha, Renato A. F. Lima, Carlos A. Peres, Otso Ovaskainen, and Pedro Jordano (2015). Defaunation impacts carbon storage in tropical forests. *Summary*:<br> Carbon storage is widely acknowledged as one of the most valuable forest ecosystem services. Deforestation, logging, fragmentation and climate change have significant impacts on tropical carbon stocks, however an elusive and yet undetected decrease in carbon storage may be due to defaunation of large seed dispersers. Many large tropical trees with sizeable contributions to carbon stock rely on large vertebrates for seed dispersal and regeneration, yet many of these frugivores are threatened by hunting, illegal trade and habitat loss. We used a large dataset on tree species composition and abundance, seed, fruit and carbon related traits, and plant-animal interactions to estimate the loss of carbon storage capacity of tropical forests in defaunated scenarios. By simulating the local extinction of trees that depend on large frugivores at 31 Atlantic Forest communities, we found that defaunation has the potential to significantly erode carbon storage even when only a small proportion (10%) of large-seeded trees are extirpated.
This chapter investigates which birds eat fruits and disperse seeds in degraded areas of two Braz... more This chapter investigates which birds eat fruits and disperse seeds in degraded areas of two Brazilian global biodiversity hotspots that have suffered intense and ongoing degradation (Atlantic Forest and the Cerrado). Focus is given on quantitative assessment of two aspects of avian frugivory, i.e. number of visits and fruits removed from fruiting plants. Aside from the taxonomic composition of this particular group of birds, some of the morphological (body mass, gape width) and behavioural traits (migratory status) that may influence their role as seed dispersers are reported. The idiosyncrasies of avian frugivory and seed dispersal in Brazilian degraded lands that are, in many aspects, likely to be similar to other disturbed areas around the world are emphasized based on comparisons with well-preserved areas.
The intensification of land‐use changes in tropical forests during the 20th century, mainly cause... more The intensification of land‐use changes in tropical forests during the 20th century, mainly caused by deforestation for agricultural uses, had an overwhelming influence on bird assemblages. However, how these historical anthropogenic changes have impacted the habitat use and diet of tropical birds is poorly known. Stable isotope analysis (δ13C and δ15N) can be useful in this regard since it provides information not only on the habitat and food resource use but also insights on the dietary niche of species. Here, we aimed to evaluate whether centenary anthropogenic impacts, mainly caused by changes in landscape composition, have affected the resource and habitat use and isotopic niche width of Neotropical birds in a region that comprises two biodiversity hotspots – the Atlantic Forest and Cerrado in southeastern Brazil. We found that the niche width of all bird guilds (frugivore, granivore, insectivore, nectarivore and omnivore) was largely reduced (28–70%) from the 20th century until recently. This niche width reduction was likely associated with historical anthropogenic impacts (e.g. fragmentation, forest loss and change in agricultural practices), which are responsible for the decrease in the availability of habitat and food resources. Moreover, the mean values of δ15N decreased over the years in all bird guilds, which might be attributed to the expansion of agricultural areas and the increase in the use of synthetic nitrogen‐based fertilizers. All the analyzed species, even though some of them are diet and habitat generalists, were strongly influenced by centenary anthropogenic actions. Our results show the consequences of human‐induced changes in land use on the diet and habitat use of tropical birds that persist in fragmented landscapes, which might compromise their long‐term survival and provide useful information to the conservation strategies of bird assemblages in modern landscapes.
Seed dispersal by vertebrates is fundamental for the persistence of plant species, forming networ... more Seed dispersal by vertebrates is fundamental for the persistence of plant species, forming networks of interactions that are often nested and modular. Networks involving angiosperms and frugivorous birds are relatively well‐studied in the Neotropical region, but there are no previous studies of networks involving waterbirds. Here, we describe the structure of a Neotropical waterfowl seed‐dispersal network and identify the species that have an important role for the network structure. We used information on 40 plant taxa found in fecal samples of five common waterfowl species to calculate the nestedness (NODF), weighted nestedness (WNODF), modularity, and weighted modularity of the network. We found that the network was nested, with yellow‐billed teal showing the highest contribution both to nestedness and weighted nestedness. Twenty‐four plant species contributed positively to weighted nestedness, with Salzmann's mille graines presenting the highest influence both to nestedness and weighted nestedness. The network was modular, but the weighted modularity was not significant. These results need to be considered with caution due to incomplete interaction sampling for two species. Ringed teal, Brazilian teal, and yellow‐billed teal were considered hub modular species. Among plants, beak sedges and water snowflake were considered modular hub species, while Salzmann's mille graines and spikerush were network connectors. The structure of this Neotropical waterbird seed‐dispersal network differed from the only previous waterfowl network study, from Europe, which found similar level of nestedness but no significant modularity. We include several possible explanations for this discrepancy and identified priorities for future research into waterbird–plant interaction networks.Abstract in Portuguese is available with online material.
The Atlantic Forest is the second largest tropical moist forest domain in South America after the... more The Atlantic Forest is the second largest tropical moist forest domain in South America after the Amazon, home to over 800 bird species (223 endemics or 27% of the avifauna). With only 28% of the original vegetation left, mostly fragmented and altered, the Atlantic Forest is a hotspot for bird conservation. We first introduce the extent, vegetation types, and exploitation history of the domain, and the composition and biogeographic affinities of its birds. We then provide an overview of the knowledge gathered so far on the ways Atlantic Forest birds thrive in the often-fragmented landscape, highlighting the landscape features that influence their occurrence and movement behavior. We end with the conservation issues affecting the Atlantic Forest birds and the actions hitherto taken to address them, including the establishment of conservation units, forest restoration, and rewilding.
Uploads