Avaliação da importância de vertebrados e invertebrados carniceiros na dinâmica local e global de remoção de carcaças de vertebrados

• Autor(a) principal: Rocha, Joedison dos Santos
• Data de Publicação: 2022
• Tipo de documento: Tese
• Idioma: por
• Título da fonte: Repositório Institucional da UFG
• Texto Completo: http://repositorio.bc.ufg.br/tede/handle/tede/12389
• topic: Cerrado; Disposição de carcaças; Fauna edáfica; Fósforo; Serrapilheira; Serviços ecossistêmicos; Urubus; Zoonoses; Carcass disposal; Cerrado; Ecosystem services; Litter; Phosphorus; Soil fauna; Vultures; Zoonoses; CIENCIAS BIOLOGICAS::ECOLOGIA

Vertebrate carcasses compose the pool of dead organic matter in the ecosystems, highlighting as a food resource for a plethora of living organisms, from microorganisms to large vertebrates. A decomposition island is established when a vertebrate dies, altering the nutrient inputs and diversity of microorganisms in the soil, as well as the composition of plant communities. Scavenger animals (invertebrates and vertebrates) are responsible for recycling nutrients from carcasses, thus preventing dead animals from accumulating in natural environments. Therefore, scavengers act both in the large-scale distribution of nutrients and in sanitation and ecosystem health. Despite this, there are several gaps regarding how these scavenger groups affect the dynamics of carcass removal and their effects on ecosystem functioning. Even basic information such as which species are involved in the removal process is scarce in the literature. The present thesis aimed to elucidate the local and global importance of vertebrate and invertebrate scavengers for: a) removal efficiency; b) nutrient cycling; and c) disease control in vertebrate carcasses, as well as d) interactions between both groups. First, an experiment using caged and uncaged carcasses (n=16) was conducted in a well-conserved Cerrado area to test the effect of loss of vertebrate actions on removal time and nutrient inputs to the soil. After 10 days, all carcasses were removed by vultures and invertebrates, without difference between treatments, suggesting that invertebrates can compensate for the absence of vertebrates. Also, the experiment showed that potassium and magnesium inputs increase in the soil around carcasses when vertebrates are absent. Besides the typical scavenger species (necrophagous flies and vultures), carcasses were largely visited by opportunistic or facultative species (e.g. wasps, butterflies, and mammals). From two global systematic reviews, we observed that the complementary activity of vertebrates and invertebrates ensures high removal efficiency compared to carcasses removed experimentally in the absence of vertebrates. Furthermore, vertebrate communities that are highly efficient in removing carcasses are typically composed of few species (<10 spp.) and higher proportion of birds. This result highlighted the functionally unique contribution provided by vultures and crows across the world. Finally, based on a model relating scavenger vertebrates to cases of zoonoses, a higher prevalence of anthrax was associated with a high diversity of facultative scavengers (e.g. eagles and mammalian carnivores), but not with the richness of vultures. Thus, the study demonstrated that vertebrate diversity represents an important factor in carcass removal efficiency. However, invertebrates can outperform vertebrate functions in certain contexts, as observed in the Cerrado. The actions of both groups affect the rates of nutrient inputs from carcasses to the soil, while partially affecting the spread of zoonoses around the world.