The lab has been conducting a series of research projects in the region since 1998, and in addition to individual proposals - information can be requested directly to our members - here we present our main projects that often engage many students and researchers with a significant amount of funding.
The SISBIOTA research network brings a series of new information that enable a greater understanding of how deforestation and some underlying processes determine the biota inhabiting anthropogenic landscapes in southern Bahia, Brazil. Our research reveals that the loss of forest cover at the landscape scale leads to severe changes in local patterns and biodiversity. Landscape scale forest loss, regardless of the size a given fragment, triggers significant changes in local forest structure, including (i) an overall reduction in the number of remaining trees, size and reduced size, (ii) less above-ground biomass and (iii) a greater density in the lower layers (5 m long). Factors such as logging and mortality were not associated with the remaining coverage, suggesting that the reduction in local density of trees in landscapes with low coverage probably derives from underlying ecological processes, such as limiting recruitment or seed dispersal. All groups of animals and plants so far investigated were negatively affected by the reduction of forest cover, with the loss of forest species that is often not offset by the increase of generalists. For most biological groups assessed we reported that the relationship between loss coverage and biodiversity occurs in non-linear manner with the detection of specific thresholds of species decay. In general, when forest cover decreases to less than 40% (30-50%), a significant loss in the richness and abundance patterns is observed for many biological groups. Of particular importance, the aforementioned erosion on the number of species and changes in the composition affected the patterns of ecological processes such as dispersal and seed predation, recruitment, control populations of arthropods, herbivory, and in some cases, we also detected such effects on gene structure and gene flow between plant populations. This is the first study empirically showing, in a comprehensive and interconnected way, the relationship between loss of forest cover the landscape, changes in species composition of a series of biological groups and its connection with important processes in maintaining the functioning of these forests. Our results also indicate that, even in landscapes retaining large tracts of forests, some ongoing human activities such as hunting activity and the introduction of exotic species have also changed key ecological processes such as dispersal and possibly recruitment of native seeds. All these results strengthen the conservation of biodiversity in these forests, species and ecological processes, should be through actions to ensure the presence of intermediate amounts (30-50%) of forest cover in landscape scale.
The “Forest Remnants of Una Region Project - RestaUna“ was one of the first multi-taxonomic inventories specifically designed to address the comparative response of many biological groups facing habitat loss, fragmentation and habitat modification. The initiative was carried out from 1998 to 2002, by a team of Ph.D. and Master Students in Ecology that together sampled trees, ferns, trees, shrubs, litter invertebrates, butterflies, litter frogs and lizards, birds, bats, small mammals and terrestrial large mammals along 36 sampling sites in a range of habitats in the Una region, southern Bahia, including edge and interior sites of small and large forest remnant and the matrix habitats such as the traditional shade cacao plantations (cabruca) and early secondary forests (capoeiras). IIn these variegated landscapes, most forest specialist assemblages are not affected by area or edge formation in forest remnants, while most alterations are associated with the proliferation of generalist species at small remnant edges. Only ferns and bats showed significant losses on forest species on edges (species composition). However, a drastic effect of fragmentation has been found on tree assemblages, with shade tolerant species from all forest strata being under-represented in smaller fragments, while those shade intolerant, disturbed-adapted species increased, particularly in the forest understory. We hypothesized that this pattern is partially explained by the demise of large and medium-sized mammals in the sampling areas, as a result of the local heavy hunting pressure.
Ecology & Conservation of Endemic and Threatned Species
Mammalian species with arboreal habit and leaf-based diet are rare and account for less than 5% of mammalian genera in the world. Within this group, primates and marsupials are better studied. On the other hand, knowledge of ecology and conservation of folivore xenarthras and rodents is incipient, particularly in South America. Our research interest is to investigate aspects of ecology of the endemic and threatened arboreal folivore mammal species from central portion of the Atlantic forest, particularly: Chaetomys subspinosus, Coendou insidiosus, and Bradypus torquatus. The main research is focused on to investigate resource and conditions requirements of this species assessing aspects of their behavior, distribution and occupation in heterogeneous landscape. Our research has shown unprecedented results on the diet, chemical ecology, activity patterns, movements, habitat selection, niche differentiation, human-use and potential distribution. Further, our research aims to understand how these species respond to environmental changes. Results have showed that these species have particularities in their requirements and threaten factors, which are critical information for conservation strategies.
Ecology of Albatrosses & petrels in Brazilian waters
When we think about Brazilian birds, the first image that that comes to our minds is the one of colorful parrots and exquisite passerines from tropical forests. However, among our rich and diverse fauna are the seabirds, comprising odd species such as the magnificent albatrosses and petrels (Procellariiformes). In fact, these birds are amongst the most threatened species in the world, being particularly vulnerable to mortality caused by fishing. In this project we aimed to analyze the data available from a series of field inventories assessing the presence and abundance of Procellariiformes along the southern parts of Brazil to model species distribution, the probability spatiotemporal of incidental catches by fishing and the impact of fishing on these populations. The study is a collaborative effort including the university and some important conservation institutions such as the Albatroz Project [D1] , BirdLife International[D2] and the International Union for Conservation of Nature[D3] , and among the results we expect to 1. identify priority areas where monitoring efforts should be intensified, 2. Identify and implement better practices to reduce the incidental catch of seabirds. Giving the expected results and the enrolment of key conservation stakeholders, we hope that this research effectively contributes to support public policies designed for marine conservation and the development of responsible fishery practices in Brazil.
Ecology of Humpback whales
Humpback whales feed in the waters of Antarctica and the Southern Ocean during the Southern Hemisphere summer, migrating north in the winter to reach warmer and protected waters to breed. The state of Bahia concentrates most of the population that uses the Brazilian coast. During the breeding season, males emit a set of sounds called songs. However whales also use other social sounds to communicate, such as vocalizations and the sounds produced at the surface of the water, result of surface behaviors. These sounds can be linked to specific social and behavioral functions concerning the composition of the groups and mediation of interactions between the different individuals presents in the groups.
Our team is studying the association between visual monitoring, from a land-based observation point, and passive acoustic monitoring (PAM) of humpback whales. The aim of the project is to describe surface and acoustic behavior from the groups sighted. We are also interested in assessing behavioral changes and whale acoustic emissions, related to the presence of background noise (wind or anthropogenic sources). From this database we intend to develop new protocols to monitoring of humpback whales that will help to mitigate the impact of anthropogenic activities.
Shade plantations and regional biodiversity
The great species richness of some agroforestry systems has led to a discussion on possibilities of conciliating agriculture and conservation in tropical agroforestry landscapes. Past and current researches of our team have evaluated patterns of native species distribution and environmental services as a function of land-use intensification and forest loss at local and regional scales. Most of our studies were developed in Una and Ilhéus landscapes, the former encompassing a mosaic of large forest tracts and small agroforest areas, and the latter dominated by cacao agroforests, with only 5% of its original forest. Forest loss at a regional (landscape) scale was proven to reduce species richness of ferns, butterflies and small vertebrates in both forest remnants and cacao agroforests. In the highly forested landscape of Una, large mammals were negatively influenced by intensification of agroforestry management (i.e. land-use intensification) but not by the loss of forest cover around the agroforest. We have demonstrated the significant contribution that traditional agroforests to landscape C storage, indicating a threat to landscape C stocks from current land use trends. Through field experiments, we have shown the role of birds and bats on the control of arthropods and cacao leaf damage in both traditional and intensively managed agroforests. With a team of collaborators we look forward evaluating conservation-development trade-offs, with further investigation of spatial patterns of terrestrial biodiversity, above-ground carbon, and the economic and social benefits of agroforestry activities across landscapes that are characterized by different percentages of forest cover.