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

Ana Cecília P.A Lopes,Márcio A Efe,Marcos Vinícius Carneiro Vital

doi:10.1590/0031-1049.2014.54.19

Abstract

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.

Highlights

Audubon’s Shearwater, Puffinus lherminieri Lesson, 1839 is a tropical seabird, mainly distributed across the Indian Ocean, throughout the northeast and central Pacific, including the Galapagos Islands (del Hoyo et al, 1992)
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
The ecological niche model generated by Maximum Entropy (Maxent) yielded a very broad potential distribution, covering the Atlantic coast ranging from Brazil to the Mexico, including Greater and Lesser Antilles (Fig. 2a, b)

Summary

Introduction

Audubon’s Shearwater, Puffinus lherminieri Lesson, 1839 is a tropical seabird, mainly distributed across the Indian Ocean, throughout the northeast and central Pacific, including the Galapagos Islands (del Hoyo et al, 1992). In western Atlantic, breeding in the island of the Caribbean Sea and Gulf of. A.C.P.A. et al.: Distribution and conservation of Audubon’s Shearwater in Brazil. Tobago was initially thought to be the breeding station closest to the South American continent (Murphy, 1936), and until 1970 no colonies were found in the South Atlantic (Bourne & Loveridge, 1978). In 1989 a breeding colony of a Little Shearwater was recorded on the archipelago of Fernando de Noronha (Antas, 1991), northeastern Brazil. Soto & Filippini (2003) and recently, Silva e Silva & Olmos (2010) confirmed that the shearwaters of Fernando de Noronha belonged to the small loyemilleri form of Audubon’s Shearwater. In 1993 another colony was recorded on the Itatiaia Archipelago, southeastern Brazil (Efe & Musso, 2001). The fact that both colonies went unrecorded until recently suggests that there may be other, unknown, colonies on some of the less well surveyed islands along the Brazilian coast (Efe, 2004)

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