Potential geographic distribution and conservation of Audubon's Shearwater, Puffinus lherminieri in Brazil

A pardela-de-asa-larga (Puffinus lherminieri Lesson 1839) é uma ave marinha tropical que ocorre entre o sul do Canadá e a costa sudeste do Brasil. Puffinus lherminieri é considerado Criticamente Ameaçado na lista vermelha do Brasil principalmente porque ocorre somente em duas localidades, ambas contendo pequenas populações. Porém, muitas ilhas ao longo da costa Brasileira são pouco conhecidas e a descoberta de novas colônias pode ser significativa para a conservação desta espécie. O objetivo deste estudo foi estimar a distribuição geográfica potencial da pardela-de-asa-larga no Brasil, baseada em modelagem de nicho ecológico (MNE) usando o algorítimo Maxent com camadas obtidas do banco de dados ambientais AquaMaps. A MNE foi baseada em 37 registros de áreas de reprodução nas Américas do Norte e Sul. O modelo mostrou uma ampla distribuição potencial, cobrindo a maior parte da costa Atlântica do Brasil e EUA. Quando filtrada para as ilhas ao longo da costa Brasileira o modelo indicou altos níveis de adequação ambiental próximo aos estados de São Paulo, Rio de Janeiro, Espírito Santo e Bahia. Porém, P. lherminieri prefere ilhas em ambientes com água quente e salina. Então, baseado na influência das correntes que atuam na costa Brasileira nós podemos inferir que colônias são mais prováveis de ocorrer em ilhas da costa da Bahia, Espírito Santo e extremo norte do Rio de Janeiro. Estas devem ser intensamente pesquisadas enquanto as ilhas ao sul de Cabo Frio devem ser descartadas. A existência de novas populações pode ter profundos efeitos no estado de conservação desta ave marinha enigmática e raramente vista.Audubon's Shearwater (Puffinus lherminieri Lesson 1839) is a tropical seabird occurring mainly between southern Canada and the southeast coast of Brazil. Puffinus lherminieri is considered Critically Endangered on the Brazilian Red List because it only occurs in two known localities, both of which contain very small populations. However, many offshore islands along the Brazilian coast are poorly known and the discovery of new colonies would be of considerable significance for the conservation of this species. The aim of this study was to estimate the potential geographic distribution of Audubon's Shearwater in Brazil, based on ecological niche model (ENM) using Maxent algorithm with layers obtained from AquaMaps environmental dataset. The ENM was based on 37 records for reproduction areas in North and South America. The model yielded a very broad potential distribution, covering most of the Atlantic coast ranging from Brazil to the US. When filtered for islands along the Brazilian coast, the model indicates higher levels of environmental suitability near the states of São Paulo, Rio de Janeiro, Espírito Santo and Bahia. However, P. lherminieri prefers islands in environments with warm saline water. Thus, based on the influence of currents that act on the Brazilian coast we can infer undiscovered colonies are most likely to occur on islands on coast of Bahia, Espírito Santo and extreme north of the Rio de Janeiro. These should be intensively surveyed while the islands south of Cabo Frio should be discarded. The existence of new populations would have profound effects on the conservation status of this enigmatic and rarely seen seabird

Foraging habitat choice of White-tailed Tropicbirds revealed by fine-scale GPS tracking and remote sensing

Background The introduction of animal tracking technology has rapidly advanced our understanding of seabird foraging ecology. Tracking data is particularly powerful when combined with oceanographic information derived from satellite remote sensing, allowing insights into the functional mechanisms of marine ecosystems. While this framework has been used extensively over the last two decades, there are still vast ocean regions and many seabird species for which information is scarce, particularly in tropical oceans. Methods In this study we tracked the movement at high GPS recording frequency of 15 White-tailed Tropicbirds (Phaethon lepturus) during chick-rearing from a colony in Fernando de Noronha (offshore of Northeast Brazil). Flight behaviours of travelling and searching for food were derived from GPS data and examined in relation to satellite-sensed oceanographic variables (sea surface temperature, turbidity and chlorophyll-a concentration). Results White-tailed Tropicbirds showed marked preference for clear and warm sea surface waters, which are indicative of low primary productivity but are likely the best habitat for preying upon flying fish. Discussion These findings are consistent with previous studies showing that foraging habitat choices of tropical seabirds may not be driven by primary productivity, as has been widely shown for non-tropical species

The importance of isolated patches for maintaining local bird biodiversity and ecosystem function: a case study from the Pernambuco Center of Endemism, Northeast Brazil

ABSTRACT The Atlantic Forest has been highly fragmented, with the Pernambuco Center of Endemism (PCE) one of the priority areas for conservation. The Mata do Cedro forest, located in Alagoas state, northeastern Brazil, is a forest fragment within the PCE surrounded by a matrix of sugarcane that acts as a refuge for several threatened bird species, some of which are endemic to the region. Here, we characterize the bird community in Mata do Cedro using measures of species abundance, frequency of occurrence, habitat use and sensitivity to human disturbance. The functional role of species was investigated with a functional dendrogram. We registered 111 species, most resident and forest dependent. The most representative trophic categories were insectivores followed by frugivores. Of the species found, 11 are highly sensitive to human disturbances and 11 are endemic to the PCE. The bird community of the fragment is highly diversified, with endemic taxa and balanced trophic categories typical of preserved tropical forests. This community structure together with the occurrence of threatened species reinforces the importance of Mata do Cedro for the maintenance of local biodiversity and ecosystem functions

Potential geographic distribution and conservation of Audubon's Shearwater, Puffinus lherminieri in Brazil

Audubon's Shearwater (Puffinus lherminieri Lesson 1839) is a tropical seabird occurring mainly between southern Canada and the southeast coast of Brazil. Puffinus lherminieri is considered Critically Endangered on the Brazilian Red List because it only occurs in two known localities, both of which contain very small populations. However, many offshore islands along the Brazilian coast are poorly known and the discovery of new colonies would be of considerable significance for the conservation of this species. The aim of this study was to estimate the potential geographic distribution of Audubon's Shearwater in Brazil, based on ecological niche model (ENM) using Maxent algorithm with layers obtained from AquaMaps environmental dataset. The ENM was based on 37 records for reproduction areas in North and South America. The model yielded a very broad potential distribution, covering most of the Atlantic coast ranging from Brazil to the US. When filtered for islands along the Brazilian coast, the model indicates higher levels of environmental suitability near the states of São Paulo, Rio de Janeiro, Espírito Santo and Bahia. However, P. lherminieri prefers islands in environments with warm saline water. Thus, based on the influence of currents that act on the Brazilian coast we can infer undiscovered colonies are most likely to occur on islands on coast of Bahia, Espírito Santo and extreme north of the Rio de Janeiro. These should be intensively surveyed while the islands south of Cabo Frio should be discarded. The existence of new populations would have profound effects on the conservation status of this enigmatic and rarely seen seabird