05-09-2019
First nest with three Bonelli eagle young birds in ten years in Catalonia
The Conservation Biology Group of the Faculty of Biology and the Biodiversity Research Institute of the University of Barcelona (IRBio), in collaboration with the Mountain support group, detected a nest with three Bonelli’s eagle young birds (Aquila fasciata) in the Natural Park of Cap de Creus. This is an exceptional finding, since only three young birds had been detected in five occasions in birds around Catalonia, more than ten years ago. Since 2005, the reproduction of this endangered species has decreased, and the average per year is less than a bird per couple.
Bonelli’s eagle breeding is rare in Catalonia, where these birds use to lay two eggs or even one only. Factors affecting high egg laying are unknown, but they can be related to an important abundance of food in the environment, with the “reproductive pause” during some seasons and singular features of the animals. Food abundance in the environment during the previous period to the egg laying allows the female to reach a good body condition and lay more eggs, as well as breeding the young birds successfully.
The nest belongs to a Bonelli’s eagle couple present in this area for two years. Actually, in 2014 they breed for the first time, and in 2015, but it has been three years the couple did not have young birds. The birds weigh enough now to fly.
More information
Since 1980, the Conservation Biology Group at the University of Barcelona has been a benchmark for research into the ecology of Bonelli's eagle.
Bonelli’s eagle breeding is rare in Catalonia, where these birds use to lay two eggs or even one only. Factors affecting high egg laying are unknown, but they can be related to an important abundance of food in the environment, with the “reproductive pause” during some seasons and singular features of the animals. Food abundance in the environment during the previous period to the egg laying allows the female to reach a good body condition and lay more eggs, as well as breeding the young birds successfully.
The nest belongs to a Bonelli’s eagle couple present in this area for two years. Actually, in 2014 they breed for the first time, and in 2015, but it has been three years the couple did not have young birds. The birds weigh enough now to fly.
More information
Since 1980, the Conservation Biology Group at the University of Barcelona has been a benchmark for research into the ecology of Bonelli's eagle.