After 130 years of mystery, a breeding colony of Mascarene Petrel has finally been discovered!

On November 15, 2016, at 11:36 AM, after more than 15 years of research carried out by an international group of ornithologists, the LIFE+Petrels project team in Reunion island successfully discovered the first breeding burrows of the Mascarene Petrel (Pseudobulweria aterrima), a species considered to be one of the 15th rarest and most threatened species in the world. This petrel, which is endemic to Reunion Island, is listed as Critically Endangered by the IUCN but the lack of knowledge on its breeding ecology has to date prevented the implementation of effective conservation actions. Thus, the discovery of this first breeding colony is a major step towards developing better conservation strategies for the protection of the species and for the preservation of the world’s natural heritage in general.

The discovery of breeding burrows will allow conservation scientists to develop a more detailed understanding of the ecology of the Mascarene Petrel, which in turn will enable the LIFE+Petrels project to implement appropriate conservative measures to stop its decline and prevent it from joining iconic species such as the Dodo on the ever-growing list of extinct species from the islands of the Indian Ocean.

Before this discovery, the Mascarene Petrel was known only from its very strange and frightening call, regularly heard in a few extremely remote areas of the island, and by a few young birds found grounded as a consequence of urban light attraction. However, without a clearly identified colony, it was previously impossible to implement targeted conservation actions.

With the LIFE+Petrels project, which has allowed for ahuge amount of fieldwork to be undertaken since January 2015 (including more than 15 000 hours of acoustic recording and thousands of hours of observational fieldwork in the most remote areas of the island), the Mascarene Petrel has been formally identified in an area of sheer cliffs located within the Saint-Joseph municipality, in the south of the island.

As the species is strictly nocturnal, Infra-red binoculars (®SAFRAN), an innovative tool acquired through a partnership with Mercantour National park, were used to track petrels in flight and allowed scientists to locate a probably breeding site location by observing where birds were landing. An abseiling expedition in this remote area on November the 15th 2016 confirmed for the first time the location ofa breeding colony.

The discovery of these active burrows gives conservationists on Reunion Island a real hope of finally being able to save this emblematic species,, whoses nocturnal calls have been feeding the Creole tales and legends of the island for many years and which is an integral part of its cultural heritage, from the cusp of extinction.

Background of this discovery

The Mascarene Petrel has been the object of occasional research by ornithologists and naturalists since the 1980s. In the past 15 years, targeted scientific research has been re-launched due to the increased extinction risk faced by the species. The population is currently estimated at approximately 50 breeding pairs. Nesting in burrows on sheer cliffs, it is the prey of introduced predators, especially cats and rats, and it also suffers from mortality induced by light pollution in urbanized areas.

The first description and representation of the Mascarene Petrel was made in 1771 by the famous artist Paul Jossigny, during the expeditions led by the naturalist Philibert de Commerson. In 1857, the ornithologist Charles Lucien Bonaparte formally described this species and named it Procellaria aterrima. A few specimens were collected in 1890, but as no further evidence of its existence was reported in subsequent decades, the Mascarene Petrel was considered extinct from the early 20th century until 1970. Two birds were found grounded in Reunion during the 1970’s, with no subsequent records for 21 years until the discovery of a dead specimen in January 1995 near Saint-Pierre city.

In 1996, a study highlighted the impact of light pollution on the survival of young petrels and shearwaters on Reunion island. In 1997, the first author of this study created the SEOR (Reunion Island ornithological NGO) and since then Mascarene Petrels have been regularly found attracted by lights and rescued, thanks to the rescue campaigns conducted each year at the scale of the entire island. The search for the Mascarene Petrel was revived.

In 2001, the first recordings of Mascarene Petrel calls were made in Grand Bassin village. Numerous campaigns were then conducted by enthusiastic local naturalists, with the support of the BNOI (environmental brigade of the Indian Ocean). This resulted in a partnership agreement between Reunion National Park and SEOR, leading to the establishment of a program to improve knowledge of this species at the end of 2008.

In 2012, a National Action Plan for Mascarene Petrel was completed in order to compile all existing knowledge on the species and to define a detailed conservation strategy for its protection. This action plan highlighted as a high priority the need to locate breeding burrows as a key early-stage objective towards the implementation of adapted conservation actions.

In 2014, in view of the urgency to save this species, local conservation scientists joined in a collaboration and obtained European Union LIFE + funding to develop an innovative conservation strategy to save the two endemic petrel species on Reunion Island from extinction. A multi-stakeholder team composed of agents from Reunion National Park, SEOR, Reunion University, the National Office for Hunting and Wildlife (ONCFS) and the BNOI, coordinated by Reunion National Park, was formed to conduct the LIFE + Petrels project. Co-financed by DEAL (Ministry of Ecology agency) and the Departmental Council of Reunion Island, this ambitious project aims at stimulating a dynamic of actions on Reunion Island and between its conservationists over a six-year period until 2020.