After being rescued from the nest, Cinereous Vulture “Aquis” is back in the wild again

Cinereous Vulture Aquis was still too young to fly when the LIFE Aegypius Return team brought it down from the nest for tagging and checking its health condition. A strange lump was visible over the bird’s eye. Concerned about its cause and potential consequences, the team transferred Aquis to a wildlife rescue centre instead of returning the chick to the nest.

Following surgery and rehabilitation, Aquis was finally released this Tuesday. In the wild, for the first time as a flying juvenile, it has been exploring the southern area of the nature park.

©SPEA/Paulo Monteiro

Cinereous Vulture Aquis hatched in the Tejo International Nature Park.

During this breeding season, the LIFE Aegypius Return monitoring teams spread across the four Cinereous Vulture colonies attentively followed the pairs and their chicks’ development. Aquis was one of the hatchlings at the Tejo International Nature Park, hatched in a place called Águas de Verão (Castelo Branco, Central Portugal) from which it got its name: aquis means water (“Águas”) in Latin.

From a safe distance, with the use of telescopes, our vulture experts can determine the right moment to tag the hatchlings in the nest. It is a complex calculation, as the chick should be big enough to hold the GPS transmitter but still unable to fly to prevent it from falling off the nest. In July, the team concluded that Cinereous Vulture Aquis was ready to be tagged and prepared the operation to bring it down from the nest.

A strange lump on Cinereous Vulture Aquis

The tagging operation involves skilled technicians, from experienced climbers to veterinarians and conservation biologists. A health check-up is performed, and biological samples are collected, which allows us to find out the hatchlings’ sex and collect their genetic information, among other valuable information.

This year, 15 Cinereous Vulture hatchlings were tagged and returned to the nest, but that was not true for Aquis. When the bird was brought down from the nest, the monitoring team was surprised to find a large lump over its eye. Unable to determine the cause of the protuberance, the team transported it to CERAS, a wildlife rescue centre managed by Quercus Association, instead of returning the chick to the nest.

Rehabilitation at CERAS Wildlife Rescue Centre

As Aquis arrived at CERAS, it was submitted to surgery by the veterinary team. With the biological samples collected, a histopathology laboratory analysis (related to diseases in tissues) was run and tested for avian pox.

Aquis was lucky. The results indicated an extensive inflammatory process associated with bacterial colonies, but no viral infection was found. Although no inclusion bodies were retrieved during the surgery, the lump probably originated from a reaction to the penetration of a foreign body, with bacterial contamination.

Back in the wild: Aquis is free again.

To ensure the bird fully recovered before returning to the wild, Aquis was kept in captivity with minimum human contact to avoid imprinting it. Although some weeks after the surgery, the inflammation was healed, the team at CERAS decided to wait until the bird could fly independently.

On 19 September 2023, Cinereous Vulture Aquis was released in the Tejo International Nature Park in a closed event with the participation of SPEA (the partner responsible for monitoring the Tejo’s colony within LIFE AEgypius Return), Instituto da Conservação da Natureza e das Florestas (ICNF) and Quercus. Ahead of the release, Aquis was fitted with a GPS transmitter, which enables us to follow its movement on its adventures across the Iberian Peninsula. So far, it has been exploring the southern area of the nature park.

©SPEA/Paulo Monteiro

The importance of monitoring Cinereous Vulture colonies

This story has a happy ending thanks to the committed team and interdisciplinary approach of the LIFE Aegypius Return project. The monitoring teams have been in the field since early February, looking for new pairs and confirming breeding success in Portugal’s four Cinereous Vulture colonies.

Monitoring and tagging chicks in the nest provides an opportunity to check their health condition and act swiftly in case they need to be rescued or rehabilitated, just as it happened with Aquis. These interventions help us increasing the breeding success and nestling survival. In addition, thanks to the data collected, we are able to analyse population dynamics, map their expansion and foresee potential areas where nesting and habitat conditions can be improved. Soon, we will reveal an updated estimation of the breeding success in Portugal this season, stay tuned.

©SPEA/Paulo Monteiro

About the LIFE Aegypius Return  

The LIFE Aegypius Return project aims to consolidate and accelerate the return of the Cinereous Vulture in Portugal and western Spain by improving habitat and food availability and minimising the main threats with capacity-building actions for national entities and agents. A joint effort by the project’s nine partner organisations, collaborating with several key entities to implement specific conservation actions in ten Natura 2000 areas along almost the entire border between Portugal and Spain. The project aims to double the population of Cinereous Vultures in Portugal to 80 pairs in 5 colonies and thus lower the national conservation status of the species from “Critically Endangered” to “Endangered” by 2027.  

The LIFE Aegypius Return is a 3.7 million project, co-financed by the European Union’s LIFE Programme, whose success relies on the involvement of all relevant stakeholders and the extensive collaboration of the leading project partner, the Vulture Conservation Foundation (VCF), with all local partners: Palombar – Conservação da Natureza e do Património Rural, Herdade da Contenda, Sociedade Portuguesa para o Estudo das Aves (SPEA), Liga para a Protecção da Natureza (LPN), Associação Transumância e Natureza (ATN), Fundación Naturaleza y Hombre (FNHY), Guarda Nacional Republicana (GNR) and Associação Nacional de Proprietários Rurais Gestão Cinegética e Biodiversidade (APNC).