The video about the ringing in Uccle

The four falcon chicks of the Saint Job church in Uccle were ringed on May 4th.

Bird ringing is one of the best ways to observe, study, and monitor wild bird populations. The system was invented by a Danish teacher in 1899 and now used around the world and still efficient.

The principle is to position at the leg of a falcon, or any other bird, a metal ring engraved with a unique code and the address of the responsible scientific institution. In Belgium, it is the Royal Institute of Natural Sciences (link to which organizes the program in the country. A network of 350 volunteer and certified coworkers marks every day thousands of birds of all species to participate in the knowledge of migration, ecology and demography of wild birds. And since birds do not know borders, data are constantly shared at a European level between scientific institutions. In addition, everyone can view the migration maps based on bird ringing started in Belgium in 1927 by connecting to the BeBirds website (link to

A ringed bird is an individualised bird. If it is found back later, it will be possible to know its movements, its behavior, its life history, by comparing the data recorded at the time of the ringing with those transmitted by the person who has the bird spotted or found.

One objective is of particular interest when ringing Peregrine Falcons: the monitoring of their survival rate, in other words their mortality. Birds are dying, that's obvious. When a Peregrine Falcon is found dead, we find it sad with our human sensitivity. It's normal. But Peregrines are no exception; they are not immortal! The death of a peregrine is therefore a process that normally has nothing to worry about. But what does that mean “normal”? Therefore, bird ringing is important. By comparing, year after year, the number of ringed Peregrines, found dead or alive, we have demographic statistics that really monitor the evolution of the Peregrine population and sound the alarm if alert. Let's not forget that they disappeared from Belgium and almost from whole Europe in the 1960s and 1990s. On the other hand, when a ringed bird is found dead, we always ask the informant systematically for the causes of death. In the specific case of Peregrines, we also will try to recover the remains for the autopsy and therefore to know the cause of death more preciously. The ringing system thus makes it possible to monitor the mortality rate from year to year, to identify the causes of mortality and to observe their evolution over time. And because ringing is done permanently, in the long term and throughout Europe, the resulting results are particularly solid and complete.

The ringing operation of the 4 falcon chicks of Uccle lasted about fifteen minutes. Each falcon was marked with a metal ring on the right leg. A second ring was placed around the left leg. This second ring is made in coloured plastic and engraved with a unique code but has only 3 characters. In most cases, the latter ring will break and disappear after a few years. But for the time being, it will allow us to identify the Peregrine from a distance, decrypting the code using a telescope.

Each falcon is measured and weighted. These data will allow to evaluate its physical condition and to know if it is a male or a female Peregrine. Females are, at the same age, indeed much heavier than their brothers.

The Peregrine family of Uccle Saint Job counts this spring 2 males and 2 females. The two males weigh respectively 667g and 701g and are marked on the left leg with a white ring with the code K / 3 and K / Y. The two females 952g and 954g. Almost the weight of an adult female! The code of their ring is K / 4 and K / 7.

Do not miss the banding film in Uccle in illustration to this blog!

Photo 1: The female pilgrim from Uccle closely monitors the banding of her falcons! (DV photo)