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Classification of frugivore species based on Bray-Curtis similarity in patterns of consumption of native plant species. Seed dispersal potential groups: 1 = High, 2 = Medium, 3 = Low; Frugivory levels: Major (open circle), Mixed (closed square), Minor (open triangle); D = seed disperser, C = seed crusher; S = small gape ( o 10 mm), M = medium gape (10-15 mm), L = large gape ( 4 15 mm).
Source publication
Habitat loss and fragmentation alter the composition of bird assemblages in rainforest. Because birds are major seed dispersers in rainforests, fragmentation-induced changes to frugivorous bird assemblages are also likely to alter the ecological processes of seed dispersal and forest regeneration, but the specific nature of these changes is poorly...
Contexts in source publication
Context 1
... UPGMA classification based on plant species consumption assembled frugivore species into five groups that broadly corresponded with frugivory level. Most major frugivores were classified together in Group 2, most mixed-diet frugivores were in Group 3 and most minor frugivores were in Group 4 (Fig. 2). Group 5 comprised species from all three frugivory levels; both major frugivore species in Group 5 were small-gaped, and the three mixed-diet species were either small-gaped or seed crushers. Group 1 contained two major frugivore species Ptilinopus superbus (a seed disperser) and Columba leucomela (a seed crusher), which had diets ...
Context 2
... to disperse plants with larger diaspores (N = 12; average diaspore size 7.7 mm) than birds in either the medium (N = 6; 4.9 mm) or low (N = 20; 1.4 mm) classes (F = 28.1, P o 0.0001). ANOSIM showed no statistical difference among the three seed dispersal potential classes in terms of their overall dietary composition (Global R = 0.05, P = 0.20; Fig. 2). However, birds in the low seed dispersal potential class were only likely to disperse relatively low numbers of plant species from all families tested (Table S3). Birds in the high seed dispersal potential class were likely to disperse the highest numbers of plant species from the families Arecaceae, Lauraceae, and Sapotaceae. Birds ...
Similar publications
Abstract
Context. Dry forests usually have a marked seasonality in resource availability; as a consequence wildlife is subjected to drastic changes in food availability during the year. The presence of high quality sites which provide food during lean periods is crucial in these habitats, especially in human-modified landscapes where resources are...
Citations
... Being connected to larger, contiguous old-growth forest has been found to be critical for the reassembly of diverse disperser communities (Barlow et al., 2007;Dent & Joseph Wright, 2009; M. E. Jones & Davidson, 2016;Luck & Daily, 2003;Moran & Catterall, 2014), including in our study area (Mayhew et al., 2019) and this, in turn, is thought to affect the dispersal of propagules across the landscape (Bello et al., 2024;Link & Fiore, 2006;Moran et al., 2004;Stevenson, 2011;Wright et al., 2000). The low degree of species overlap between recruitment and potential seed trees in the adjoining 150m long segment of the stream-side forest fragments indicates that many seed sources were from further away along the streamside forest fragment. ...
Large scale reforestation is promoted as an important strategy to mitigate climate change and biodiversity loss. A persistent challenge for efforts to restore ecosystems at scale is how to accelerate ecological processes, particularly natural regeneration. Yet, despite being recognized as an important barrier to the recovery of diverse plant communities in agricultural landscapes, the impacts of dispersal limitation on natural regeneration in secondary forests – and especially how this changes as these forests grow older – is still poorly studied at local and landscape scales. Here, we evaluate the multi-scale impacts of proximity to a connected network of forest fragments on recruitment in 1–40-year-old secondary forest. We used eight years of annual census data from 45 sites with paired plots, one directly adjoining a streamside forest fragment and the other further uphill, and a null model approach to test the effects of basal area and proximity to streamside forest fragments. In general, we found that proximity to streamside forest fragments enhanced multiple aspects of recruitment across spatial scales, including species diversity and the proportion of rarer and less-widely distributed species among the recruits. Unexpectedly, this effect did not weaken over time, despite a fast increase in stand basal area, canopy complexity and diversity. This suggests that successional changes in forest structure may not be sufficient to attract the animals that disperse rarer tree species. Our results provide empirical evidence to guide restoration initiatives in agricultural landscapes in tropical regions, principally prioritizing the restoration of forest corridor networks along streams, while also highlighting the knowledge gap about restoring animal dispersers in secondary forests.
... In particular, habitat loss has affected tropical forests, threatening their rich associated biota (Arroyo-Rodríguez et al., 2020;Morante-Filho et al., 2015;Rocha-Santos et al., 2016). Several studies have reported that this disturbance in tropical forests cause the loss of species (Lima & Mariano-Neto, 2014), ecological processes (Moran & Catterall, 2014) and genetic variability (González et al., 2020). ...
Human activity has diminished forests in different terrestrial ecosystems. This is well illustrated in the Brazilian Atlantic Forest, which still hosts high levels of species richness and endemism, even with only 28% of its original extent remaining. The consequences of such forest loss in remaining populations can be investigated with several approaches, including the genomic perspective, which allows a broader understanding of how human disturbance influences the genetic variability in natural populations. In this context, our study investigated the genomic responses of Euterpe edulis Martius, an endangered palm tree, in forest remnants located in landscapes presenting different forest cover amount and composed by distinct bird assemblage that disperse its seeds. We sampled 22 areas of the Brazilian Atlantic Forest in four regions using SNP markers inserted into transcribed regions of the genome of E. edulis, distinguishing neutral loci from those putatively under natural selection (outlier). We demonstrate that populations show patterns of structure and genetic variability that differ between regions, as a possible reflection of deforestation and biogeographic histories. Deforested landscapes still maintain high neutral genetic diversity due to gene flow over short distances. Overall, we not only support previous evidence with microsatellite markers, but also show that deforestation can influence the genetic variability outlier, in the scenario of selective pressures imposed by these stressful environments. Based on our findings, we suggest that, to protect genetic diversity in the long term, it is necessary to reforest and enrich deforested areas, using seeds from populations in the same management target region.
... pollination: Bennett et al., 2020; seed dispersal: Rogers et al., 2021), or examined only one group of mutualistic partners, rather than the actual interactions (e.g. plants: Franklin et al., 2016;pollinators: Millard et al., 2021; seed dispersers: Moran and Catterall, 2014), or one factor broadly included within global changes (e.g. fragmentation: Magrach et al., 2014;Fontúrbel et al., 2015a). ...
Global anthropogenic changes cause major impacts on species interactions, with
cascading effects on ecosystem functioning. Animal-mediated pollination and seed
dispersal are major mutualisms associated with distinct stages of plant reproduction.
Nevertheless, we lack an integrated assessment on how multiple anthropogenic
impacts affect these interrelated mutualisms. Here, we systematically reviewed the
effect of the most important global anthropogenic factors (agrochemicals, climate
change, fire, fragmentation, hunting, non-native species and urbanization) on
pollination and seed dispersal. We evaluated which anthropogenic factors, mutualisms
and their combinations have been more frequently investigated, the biogeographic and
taxonomic tendencies and the most frequently recorded effects of anthropogenic
factors. We show that pollination has been more broadly investigated, that the impacts
of the anthropogenic factors on pollination and seed dispersal are biased towards the
temperate region and forest biomes and lack representation from some relevant
groups, such as mutualistic bats. Moreover, some anthropogenic factors have been
more studied for one mutualism type in relation to the other, for instance,
agrochemicals and urbanization on plant-pollinator interactions, even though these
impacts could also generate direct and cascading effects on frugivores and seed
dispersal. The predominance of negative effects observed, especially of climate
change on plant-pollinator and non-native species on plant-frugivore interactions
deserve special attention. Finally, we identify a gap in empirical studies that
simultaneously consider pollination and seed dispersal as integrated components of
plant reproduction, and combined anthropogenic factors in the same ecosystem,
which are needed to better understand the vulnerability of plant-animal mutualisms in a
changing world.
... This pattern should be particularly the case of mature-forest, shade tolerant species, many of which are especially vulnerable to changes in abiotic factors (e.g., water stress, soil or air humidity or wind damage: Turner 1996, Scariot 1999, Benítez-Malvido & Martínez-Ramos 2003, Lasky et al. 2013, Jin et al. 2020 and biotic factors such as pollinators and dispersers (e.g., Cordeiro & Howe 2001, Osuri et al. 2017. This latter expectation is consistent with documentation of the negative impact of fragmentation on animals that play such roles (e.g., Aguilar et al. 2006, 2008, Cramer et al. 2007, Moran & Catterall 2014. In contrast, light-demanding species are less likely to be affected by the abiotic changes associated with fragmentation. ...
Background:
Tropical rain forests have been impacted by land use change, leading to major deforestation and fragmentation. Understanding how fragmentation impacts plant communities is central for tropical conservation.
Questions:
i) How does species richness vary across a range of fragment sizes, and does it vary with plant size-structure? ii) how are species composition and floristic similarity affected by forest fragmentation? iii) does habitat fragmentation affect the representation of species with different life-history and regeneration patterns?
Studied species:
We sampled overall plant communities and calculated diversity metrics of mature-forest and light-demanding species, considering plants of different size-categories (defined by diameter at breast height, DBH).
Study site:
This study was carried out at Los Tuxtlas, Veracruz, Mexico, an area originally dominated by extensive evergreen tropical forest, but currently highly fragmented
Methods:
We sampled plants in five forest fragments representing (2 - 36 ha), a large patch of continuous forest (700 ha). Within each site we established ten-50 × 2 m transects and registered all woody plants with DBH > 1 cm.
Results:
Species richness declined as fragment size became. Such decline was significant considering all plants (DBH > 1.0 cm) but became non-significant as plant size-category increased (DBH > 2.5, or > 10 cm.). Small fragments had distinguishable assemblages compared to continuous forest and also a reduction in the representation of mature-forest species, compared to light-demanding species.
Conclusions:
Our findings confirm that fragmentation affects tropical plant species diversity, but the effect is differential, depending on plant size-category and life history.
... However, the proneness of extinction can vary even among sensitive species. In particular, frugivorous birds show a greater vagility and ability to use complementary habitats to obtain food (Moran and Catterall, 2014) compared to insectivorous species, which require specific local characteristics in forest patches (Stouffer and Bierregaard, 1995). ...
Biodiversity-friendly agricultural systems allow the maintenance of native species even in highly fragmented landscapes by providing corridors to species dispersion and offering supplementary resources for animal populations. In the tropical region, cocoa agroforestry systems are of great importance for biodiversity conservation as they maintain part of the native vegetation, and therefore can be used by the local fauna. In this system, understory of native forests is replaced by cocoa trees, which are shaded by large old-growth trees. However, the persistence of native species in cocoa agroforests depends on local vegetation characteristics but also the landscape structure in which these systems are located. Here, we investigated the influence of landscape composition (i.e. amount of forest cover, cocoa agroforestry and cattle pasture) and local vegetation structure (i.e. number of native and cocoa trees, basal area of native trees and canopy closure) on understory birds in 18 cocoa agroforestry systems located in three regions in the Brazilian Atlantic forest, presenting distinct land use contexts. Specifically, we assessed the effects of these landscape and local features in predicting richness and abundance patterns of the entire community, and also in distinct ecological groups, such as forest-dependent and non-forest-dependent birds, and insectivores, frugivores, and omnivores. Using generalized linear models and Akaike information criterion, we observed lower species richness of complete community, non-forest and omnivorous birds in the most deforested region. Also, our findings demonstrated that cocoa agroforests integrated in more forested landscapes harbor greater richness and abundance of frugivorous birds. Conversely, the increase in cattle pasture amount at the landscape had a harsh effect on all bird groups evaluated. Regarding local vegetation, we observed that the increase of canopy closure leads to greater abundance of insectivorous birds in cocoa agroforestry systems. Similarly, abundance of non-forest species increased in agroforests with higher number of cocoa trees. Our study demonstrated that cocoa agroforestry systems can provide complementary habitats for many species, including forest birds, and therefore can mitigate the effects of habitat loss. However, this key benefit for bird conservation will be more effective when these agroforestry systems are located in more forested landscapes, with low amount of cattle pastures. Our findings therefore reinforce the alarming need to maintain and recover landscape-scale forest amount to ensure species persistence of birds in anthropogenic landscapes, even in those comprising biodiversity-friendly land uses such as cocoa agroforestry systems.
... Do mesmo modo, a presença de espécies endêmicas da Mata Atlântica também está diretamente atrelada aos remanescentes de floresta ombrófila densa adjacentes. Grande parte dessas espécies são aves frugívoras (39%), que necessitam ser bastante móveis devido à efemeridade da oferta de recursos alimentares (Moran & Catterall 2014, Rother et al. 2016, Rumeu et al. 2019, Gonçalves da Silva et al. 2020. Enquadram-se aqui táxons ameaçados como Xipholena atropurpurea, C. melanocephala e C. maculata, considerados importantes dispersores de sementes (Kirwan & Green 2011, Morante-Filho et al. 2015, os quais, embora florestais, eventualmente foram observados se alimentando de frutos como os de Simarouba amara e Byrsonima sericea nas muçunungas gramíneo-lenhosas (Godoy 2018). ...
AVIFAUNA ASSOCIATED WITH MUÇUNUNGAS: COMPOSITION AND USE OF THE
HABITAT: Muçunungas are vegetation formations in sandy soils, similar to restingas in
structure and composition, ranging from grassy woody (GL) to low-density trees or muçununga forests (FM). Although some birds are known for this phytophysiognomy, few data are availableon the structure of their communities, and on the ecological resources' use. This research aims topresent the first commented list on the birdlife of muçunungas, and to describe how they share the ecological resources in different formations. Five areas of muçunungas having different vegetation structures were sampled in southern Bahia, Brazil, between 2011 and 2019. We recorded 216 species; 32 endemics to the Atlantic Forest and 14 threatened with extinction. The most abundant feeding guilds were insectivores (77 species), omnivores (53), and frugivores (32).A total of 109 species were recorded in FM and 183 in GL. Strictly forest birds prevailed in FM (66 %), and forest, semi-forest, and open-area species were detected in similar amounts in GL. Generalist birds have prevailed in muçunungas, sharing many species with the surrounding environments, as in restingas. Due to the paucity of specific public policies, and similarities of muçunungas and restingas, we suggest that similar conservationist strategies could be applied to birds in these two environments of the Atlantic Forest.
Keywords: Atlantic forest; endemism; grasslands; restingas.o
... Most rainforest trees and shrubs bear fleshy fruits whose seeds are dispersed by mobile vertebrates, especially birds (McConkey et al., 2012;Moran and Catterall, 2014). Areas of pasture, however, are infrequently visited by most seed-dispersing birds because they typically lack suitable habitat attributes such as above-ground woody vegetation with adequate perch sites (Willson and Crome, 1989;Holl, 1998) and a supply of fleshy fruits (Wunderle, 1997). ...
... Even when areas of young regeneration are visited by seed-dispersing birds, these may not include large frugivores (Vogel et al., 2018), capable of dispersing large-seeded rainforest trees (McConkey et al., 2012;Moran and Catterall, 2014;Freeman et al., 2015). Large-seeded trees are then under-represented in regenerating forest even though they comprise a large proportion of tree species in old-growth rainforest (Saavedra et al., 2015;Shoo et al., 2016). ...
... The avian seed-disperser community in the old-growth rainforest adjacent to our experimental plots was abundant, diverse, and dominated by individuals and species capable of ingesting and dispersing large seeds. Many of these birds are specialists of intact rainforest and their abundance is reduced in rainforest fragments and advanced regrowth (Moran et al., 2004;Dennis and Westcott, 2006;Catterall et al., 2008;Moran and Catterall, 2014;Freeman, 2015). Despite the plentiful supply of seed dispersers close to our regeneration plots, almost all avoided both the scattered pasture trees and semi-natural perches within tens of metres of the rainforest edge. ...
Providing water near perches, and suppressing pasture growth, may enhance bird-mediated rainforest seed dispersal into disused pasture.
... Considering foraging guilds, we expect insectivores to be more vulnerable than other guilds due to their dependence on insects, which in turn, require specific regimes of micro-climate and specific sets of vegetation structural attributes (Thiollay, 1997;Sekercioğlu et al., 2002;Silveira et al., 2010). Frugivores on the other hand are expected to be less affected by local forest structure since they are more wide-ranging, having the ability to locate resource-rich patches in a heterogeneous landscape (Canaday, 1996;Moran and Catterall, 2014;Morante-Filho et al., 2015). Granivores and omnivores may not be affected significantly by anthropogenic disturbance as they adapt well to resources present around cultivation and human settlements (Thiollay, 1992;Watson et al., 2004;Schulze and Riedl, 2008). ...
... In many studies, frugivores do not appear to be as vulnerable to forest extraction as insectivores, a pattern borne out by our study (Thiollay, 1992;Canaday, 1996;Gomes et al., 2008). This can be attributed to their wide-ranging behaviour which allows them to locate widely-dispersed fruiting trees (Thiollay, 1997;Moran and Catterall, 2014). Further, there were no large frugivores such as hornbills in our study area, which tend to be far more specialised in their nesting and feeding requirements and hence more vulnerable to habitat degradation (Gomes et al., 2008;Velho et al., 2012). ...
... With the global demand for increased food production, agriculture is in increasing world expansion [1,2], mainly in tropical countries [3]. This is one of the main activities causing reduction and fragmentation of natural forests worldwide [4] and occupies almost 40% of the soil throughout the planet [5]. Thus, agricultural landscapes are today seen as areas of extreme importance for studying and developing strategies that integrate biodiversity conservation and ecosystem services with food production [2,6]. ...
... Thus, it is possible to observe that the pioneer or secondary heliophilous species may be benefiting in the fragments within an intensive agriculture environment, where the effects of nutrient drift are greater. When analyzing the two functional groups (heliophilous and sciophilous), it is possible to observe that fast growing pioneer species generally present higher rates of primary production in response to nutrient increase [4,70,71]. ...
... However, despite the influence of changes in soil fertility demonstrated in the results of our study, this variable does not solely explain the composition of the functional diversity in the fragments. The environment can affect the composition of the species in two ways: firstly by edge effects, which are more intense when the environmental matrix is agricultural, changing the chemical characteristics of the soil and creating direct impacts on the microclimate; and second, by factors that hinder the recruitment of late successional species by reducing propagule flow [4,14,[72][73][74]. ...
Agricultural landscapes are seen as areas of extreme importance for studying and developing strategies which integrate biodiversity conservation and ecosystem services with food production. The main strategies for intensifying agriculture are based on conventional agricultural practices of frequently using inputs for fertilization and correcting soil pH. Some studies show that these practices generate impacts on nearby forest fragments through soil contamination and increasing nutrient content. The objective of this study was to identify the impacts on the functional groups of sciophilous (late successional/shade-tolerant species) and heliophilous (pioneer/sun-loving) species of a tree community of 14 forest fragments near pasture areas and agricultural areas under conventional practices, raising the hypothesis that higher-fertility forest fragments adjacent to intensive agriculture modify the floristic composition of the tree community. Consequently, this study is based on the following questions: i) Do forest fragments within intensive farming environments present differences in floristic composition of species?; ii) Does the soil fertility influence the tree species composition?; iii) Which variables influence species abundance and richness in the forest fragments with different types of use around their environment? The floristic composition of fragments close to agricultural areas are more similar to each other than the composition of fragments close to pasture areas. Furthermore, the General Linear Model (GLM) results show a clear influence of the intensive farming environment on the richness and abundance of the two functional groups in the forest fragments, directly benefiting the abundance of heliophilous species, which are also benefited by the greater declivity and smaller fragment area, while the abundance of sciophytes is negatively correlated with these last two variables. The increase of calcium content is beneficial for the richness of heliophilous species, while the increase in phosphorus content influences a reduction in the richness of sciophyte species, which also strongly respond to the isolation between fragments. The results indicate a dominance trend of pioneer species in fragments with nutritionally enriched soils, providing evidence that the intense adoption of inputs in cultivated areas causes concrete impacts on the diversity of the tree community.
... Whereas it may be easier for highly mobile and generalist species to find new suitable habitat, specialists are thought to be more prone to extinction due to the loss of adequate environmental conditions (e.g. Brook et al., 2003;Ferraz et al., 2007;Moran & Catterall, 2014;Morante-Filho et al., 2015;Waltert et al., 2005). Understanding the response of the most vulnerable bird groups and species to habitat loss provides an insight into the minimum habitat requirements needed for their persistence in a given landscape. ...
Afrotropical ant-following birds are vulnerable to forest loss and disturbance, but critical habitat thresholds regarding their abundance and species richness in human-dominated landscapes, including industrial oil palm plantations, have never been assessed. We measured forest cover through Landsat imagery and recorded species richness and relative abundance of 20 ant-following birds in 48 plots of 1-km², covering three landscapes of Southwest Cameroon: Korup National Park, smallholder agroforestry areas (with farms embedded in forest), and an industrial oil palm plantation. We evaluated differences in encounter frequency and species richness among landscapes, and the presence of critical thresholds through enhanced adaptive regression through hinges. All species were detected in Korup National Park and the agroforestry landscape, which had similar forest cover (>85%). Only nine species were found in the oil palm plantation (forest cover = 10.3 ± 3.3%). At the 1-km² scale, the number of species and bird encounters were comparable in agroforests and the protected area: mean species richness ranged from 12.2 ± 0.6 in the park and 12.2 ± 0.6 in the agroforestry matrix to 1.0 ± 0.4 in the industrial oil palm plantation; whereas encounters decreased from 34.4 ± 3.2 to 26.1 ± 2.9 and 1.3 ± 0.4, respectively. Bird encounters decreased linearly with decreasing forest cover, down to an extinction threshold identified at 24% forest cover. Species richness declined linearly by ca. one species per 7.4% forest cover lost. We identified an extinction threshold at 52% forest cover for the most sensitive species (Criniger chloronotus, Dicrurus atripennis, and Neocossyphus poensis). Our results show that substantial proportions of forests are required to sustain complete ant-following bird assemblages in Afrotropical landscapes and confirm the high sensitivity of this bird guild to deforestation after industrial oil palm development. Securing both forest biodiversity and food production in an Afrotropical production landscape may be best attained through a combination of protected areas and wildlife-friendly agroforestry.
