Increase in Shearwater Nests Linked to Shrub Expansion
It is noteworthy that the number of nests has increased more rapidly in areas where there has been an expansion of shrub cover, under which the Cory’s shearwaters (Calonectris borealis) can nest. This expansion is a result of the recovery of vegetation on Selvagem Grande following the eradication of rabbits and mice in 2002, explains Paulo Catry.
Paulo Catry, a researcher at MARE – Center for Marine and Environmental Sciences, part of ISPA – Instituto Universitário, is one of the coordinators of the study, alongside José Pedro Granadeiro from the Center for Ecology, Evolution, and Environmental Changes (CE3C) at the Faculty of Sciences, University of Lisbon.
Growth of Shearwater Population
The study, published by the University of Cambridge in the UK on January 20, reveals that the population of Cory’s shearwaters in the Selvagens has grown at an annual rate of 1.45% since 2009. According to the researchers, shearwaters, like most pelagic birds, face various threats. These include accidental capture in fishing gear, collision with sources of light pollution, introduced predators on islands, marine pollution—especially from plastics—and declining ocean productivity related to climate change.
Conservation Efforts Yield Positive Results
Despite these threats, “the growth of this important population of shearwaters demonstrates that the conservation efforts undertaken, particularly the complete protection of the Selvagens and their management by the Institute of Forests and Nature Conservation of Madeira, have had very positive impacts,” emphasizes Paulo Catry.
About the Selvagens
The Selvagens, a subarchipelago of Madeira located about 300 kilometers south of Funchal, consists of two main islands and several islets. It represents the southernmost territory of Portugal and was classified as a natural reserve in 1971. In March 2022, the reserve was expanded from 92 to 2,677 square kilometers, covering a 12-nautical-mile area around the islands where fishing and any other extractive activities are prohibited. This makes it the largest fully protected marine area in the North Atlantic.
Temporary Authorization for Research
In July 2024, the Regional Secretariat for Agriculture, Fisheries, and Environment announced that it had temporarily authorized the capture of bait fish in the reserve for research and monitoring purposes.
Stay tuned for more updates on this ongoing conservation effort and its impact on the local ecosystem.
