April 7th, 2025
The Manx shearwater (Puffinus puffinus canariensis) is one of the least-known seabirds in the Canary Islands. With just a few confirmed but aging breeding sites scattered across the archipelago, the Manx shearwater remains a rare sight. Locally, it is known as estapagao, a name inspired by the bird's haunting, wailing calls that echo through the night. Historical records suggest that the species once had a more widespread presence, but habitat loss, introduced predators, and human disturbance have driven populations to near invisibility. In La Palma, its status remains largely uncertain—suspected but unconfirmed for decades. Our last confirmed distribution data dates back to 1989! Until now, the only clues to its presence were occasional at-sea observations and sporadic calls detected at night in remote valleys. With this in mind, we embarked on our fieldwork in La Palma.
Previous Efforts
Aware of the critical status of the Manx shearwater population in the Canary Islands, our team has made two dedicated research trips to La Palma: the first in 2006 and the second two years ago. During the initial expedition, a single Manx shearwater was captured at sea, confirming the species’ presence in the area. However, no further clues about nesting locations could be identified. In the more recent expedition, we adopted a different approach—relying on expert climbers, thermal binoculars, and even a trained sniffer dog to search for potential nests in the rugged terrain surrounding Los Tilos.
Yet the island once again demonstrated how challenging it is to study this species, with nests largely remaining out of reach, hidden deep within steep ravines and dense vegetation. These difficulties emphasized the need for a new strategy, one that would combine cutting-edge tracking technology with traditional fieldwork to finally shed light on this elusive population.
Pictures of the 2006 expedition. Credit: Raül Ramos.
Pictures of the 2023 expedition.
Arrival to La isla bonita
Upon arrival in La Palma in mid-February, the first thing that struck us was the island’s rugged beauty—steep cliffs and ravines, lush forests and misty mountains. Our team in the island was led by research assistant Adrián Pina, with José Luis Correia, from Projecto Vitó, as the drone pilot; and Adrien Lambrechts and Jérome Cabelguen from the French Biodiversity Agency (OFB). The first few days were all about setting up the following fieldwork: checking equipment, identifying from the cliffs the best rafting areas where shearwaters congregated at sea, and scouting secluded valleys ideal for deploying sound recorders and conducting nocturnal observations.
Picture credit: Jérome Cabelguen, French Biodiversity Agency (OFB).
Into the field
Identifying shearwater rafts from land was a challenge. Their petite size and the vast distance made species-level identification difficult, requiring patience, keen observation, and favorable lighting conditions. Even with a potent telescope, distinguishing a Manx shearwater from the more numerous Cory’s shearwaters was no easy task.
A crucial part of our research was deploying sound recorders in the steep ravines and valleys where the Manx shearwaters breed. These areas, nestled among the laurisilva—relict forests that date back to the tertiary period—presented unique challenges. The terrain was treacherous, with dense underbrush and jagged rocks to navigate. Still, it is the perfect environment to monitor their nocturnal vocalizations. We positioned the recorders hoping to capture data on their calls and behaviour during the breeding season that might indicate possible nesting areas.
Our first close encounters with shearwaters were at sea. With the help of local boat operators (Miguel and Kevin Cabrilla), we approached the rafting flocks we had previously identified from land to confirm species presence. On the first day, there it was—amidst the hundreds of Cory’s shearwaters, a Manx shearwater, the focal species of our fieldwork. From then on, our pelagic expeditions began, all over the north-eastern part of La Palma, from Santa Cruz to Garafía—surveying Manx shearwaters, estimating their numbers, and testing how close we could get before they took flight.
With thermal binoculars and a drone, piloted by José Luis Correia, we also inspected the ravines at night. The drone provided a bird's-eye view of these inaccessible areas, and with thermal imaging, we were able to spot shearwaters flying in circles above certain patches of forest. It was a thrilling moment—the first clues of possible nests for this endangered species in more than 20 years!
Video and pictures credit: Adrián Pina
Following their flight
On the 20th of March, our full team was finally reunited, marking the beginning of our most intense fieldwork. Adrien and Jérome joined us to assist in capturing the Manx shearwaters at sea with their advanced equipment. Armed with a net gun, exceptional skill, and remarkable patience, we successfully captured our first Manx shearwater, despite the challenging sea conditions.
The Atlantic Ocean did not make things easy. Strong winds, sudden rain showers, and waves crashing against our boat, drenching us, a relentless reminder of how rough fieldwork conditions can be in nature.
After nine days of intense work—sometimes interrupted by harsh weather conditions—we successfully deployed six GPS-GSM devices from Ornitela on this little-known species. These devices provided us with the first-ever tracking data of its kind, offering invaluable insights into their movements. For the first time, we gathered crucial information about possible nesting areas, their ecology, and their behavior at sea, marking a significant step forward in understanding this endangered population.
Positions of the tagged shearwaters from March 20th to April 7th.
Maps credit: Diego Vicente
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Picture credit: José Luis Correia
Looking into the future
This fieldwork was carried out within the framework of AMPLIAMAR, a project led by the Professor Jacob González-Solís and coordinated by the early-stage researcher Diego Vicente, both from the Biodiversity Researsh Institute (IRBio) at the University of Barcelona. This project aims to expand Spain’s network of marine protected areas by identifying Key Biodiversity Areas (KBAs) for seabirds and other marine species. By deploying GPS-GSM trackers on Manx shearwaters, we contributed to one of AMPLIAMAR's core objectives: expand our knowledge about sensitive seabird species poorly studied. The movement data obtained over the following weeks will not only improve our understanding of this little-known population but also support the identification of Key Biodiversity Areas, which we hope will contribute to extend the current network of Marine Protected Areas in Spain (RAMPE) to safeguard their habitat. Additionally, our findings on potential nesting sites in La Palma align with AMPLIAMAR's efforts to integrate conservation science with policy, ensuring data-driven protection measures for the region’s marine biodiversity.
The data we collected during our fieldwork will play a crucial role in MAC Puffinus LIFE2030: Conservation of the Manx Shearwater in Macaronesia, a comprehensive initiative under the BESTLIFE2030 Programme aimed at safeguarding this species in Macaronesia, with the participation of the Seabird Ecology Lab at the Universitat de Barcelona.
Our tracking data and observations will help identify previously unknown breeding areas, a key objective of the project. By pinpointing nesting sites and understanding their habitat requirements, conservation efforts can be more effectively targeted. Additionally, our findings will support the long-term monitoring of these nests, providing insights into the species' breeding ecology. This knowledge is essential for mitigating terrestrial predators—particularly invasive rats—that threaten colonies. Beyond direct conservation actions, MAC Puffinus LIFE2030 also seeks to raise public awareness, fostering a shared responsibility for protecting the Manx shearwater across its range.
Both projects are supported by the Fundación Biodiversidad, under the Ministry for Ecological Transition and Demographic Challenge. AMPLIAMAR project is also funded through the Pleamar programme co-financed by the European Maritime, Fisheries, and Aquaculture Fund (FEMPA) of the European Union.
This is just the beginning. The data we have gathered will now be analyzed to refine our understanding of the species’ habitat use and threats, helping to inform conservation strategies. Future work will focus on confirming nesting sites, mitigating threats from invasive predators, and continuing collaborations with conservation programs and local stakeholders. With each new discovery, we move closer to securing a future for the Manx shearwater in La Palma and beyond.