Off the coast of Andalusia, particularly in Cádiz and Huelva , lives what is likely the last stable population in Europe of the giant guitarfish ( Glaucostegus cemiculus ). This species of cartilaginous ray, related to sharks, has disappeared from most of its original range, tenaciously resisting extinction in a small corner of southern Spain. It is currently listed as critically endangered by the International Union for Conservation of Nature (IUCN), meaning its future depends essentially on the conservation efforts underway there.
For decades, this peculiar animal, which can grow up to two and a half meters long and weigh over 30 kilos, was a relatively common sight along the Atlantic coast and in parts of the Mediterranean. Today, spotting a snipe is an extraordinary event ; bycatch, habitat loss and destruction, and human pressure have been key factors in its alarming decline. Its slow reproductive rate, with gestations lasting up to nine months, makes the species' recovery especially difficult, even if the threats disappear.
Glaucostegus Project: International Collaboration and Citizen Science
In response to this situation, the Glaucostegus Project has become a European benchmark for the study and protection of the giant guitarfish. A consortium of organizations, including the Oceanogràfic Foundation, the Blue Marine Foundation, the Seville Aquarium, and the LAMNA Association , along with universities and public bodies, have joined forces with scientists, institutions, and ordinary citizens to tackle this challenge.
Under the coordination of Dr. Jaime Penadés , the project has established the systematic collection of scientific data and citizen observations since 2018, the year in which Ángel Benítez encouraged the involvement of recreational fishermen and volunteers in the area. Through photos, videos, and data associated with bycatch (date, location, fishing method), more than 80 confirmed sightings have been compiled in recent years, which is fundamental to understanding and better protecting the species.
The application of simple and effective protocols has allowed, in addition to documenting the presence of the guitarfish, confirming its reproduction in Andalusian waters (including newborn specimens) and detecting pockets of poaching; from cases of specimens thrown in the trash on beaches like Valdelagrana, to stories of illegal sales in restaurants.
Scientific campaigns and the hope of the ex situ reproduction plan
Fieldwork is not limited to simply collecting testimonies. Scientific sampling campaigns have intensified our knowledge of the species' biology and status. A prime example was the operation at Valdelagrana Beach in late May 2025, where more than 40 researchers examined 33 guinea fowl, both juveniles and adults, following protocols that minimize stress and ensure animal welfare.
During these campaigns, DNA and blood samples are collected , and biometric measurements and studies are performed to assess the population's health status and detect potential health or genetic risks. The entire process is authorized by the relevant authorities (MITECO, the Regional Government of Andalusia, and the Doñana Biological Station), providing institutional support for the initiative.
One of the most promising avenues being explored is the ex situ breeding program . This involves genetically comparing specimens from the wild with those in the zoological collections of some of the most important aquariums on the Iberian Peninsula. The objective is twofold: to assess genetic diversity for potential captive breeding programs, and to prepare for the future reintroduction of the guitarfish to areas where it has now disappeared but which are considered safe.
An emblematic species of marine conservation in Europe
The guitarrón, besides being an icon of Andalusian biodiversity, is becoming an international symbol of the urgent need to protect threatened marine species . The collaborative work of researchers, NGOs, recreational fishermen, and government agencies demonstrates that, although the situation is complex, there are still ways to prevent the extinction of this unique animal.
The key lies in the collaboration between civil society and the scientific community . Thanks to this collective involvement, significant progress has been made in just a few years, opening the door to new conservation strategies and a shift in public opinion regarding the ecological and heritage value of a species that, until recently, went largely unnoticed.
Although the guitarrón remains in an extremely precarious situation and faces risks such as illegal fishing, habitat destruction, and pressure against its conservation, recent efforts offer reasons for optimism . The Andalusian experience demonstrates that it is still possible to reverse the fate of endangered species if swift action is taken, with collaboration and a commitment to biodiversity.
