XJ Nikola: one of the first released griffon vultures from Eindhoven Zoo

Zivka and Stanislav are not the only griffon vultures released into the wild in Bulgaria. Seven years ago, XJ Nikola hatched and was raised by the successful pair at Eindhoven Zoo. Griffon vultures reach sexual maturity around the fifth year of life and then start looking for a mate for life.

Two years after Nikola hatched, the vulture moved to Bulgaria as part of a project by Green Balkans. Green Balkans is committed to several conservation projects, and one of them is to maintain and increase the population of vultures in Bulgaria. Green Balkans does this by releasing the vultures into the wild.

Once in Bulgaria, near the city of Sliven, Nikola was able to get used in a separate aviary. Not much later, he was released into the Sinite Kamani Nature Park.

Nikola received a tracker and because of this, Green Balkans knows where Nikola is located: dozens of kilometers north of the release point. Green Balkans' released vultures also receive a wing tag and are ringed. Partly because of this, it is easier for Green Balkans volunteers to observe the vultures, this is done, for example, at resting sites and nesting cliffs.

Thanks to the tracker and observations, Nikola is known to have found a female. The female vulture is not known to Green Balkans, so it probably forms a pair with griffon vulture born in the wild. In 2022, they successfully raised a chick together! The year 2023 was unfortunately less successful and that is probably due to the bad weather conditions this year.

Griffon vultures form a pair for life. Each year, the griffon vulture lays one egg and when it fails to hatch, a second laying occurs.

Want to know more about the project? Read more here!