The fledging of the 4 ULB juvenile falcons in 9 videos
They did it! The 4 juvenile falcons fledged this week.


The second falcon from Uccle fledged
We cannot deny that the fledging of the two juvenile Peregrine falcons of Uccle is fast this year! While in general, they spend hours, days, "wandering" around the clock dial, returning to the nest, balancing on the clock hands which obviously... move constantly, this spring: it was like one, two, three, fledge!
Fledging at Uccle and first flying exercises at the ULB.
It was planned or rather expected: one of the two male Peregrine falcons hatched on April 15, fledged this Tuesday, 28th of May! The second is, this 29th of May, still in the nest.
Fledging is imminent in Uccle
The juvenile Peregrines from the Saint Job church in Uccle hatched on the 14th and the 15th of April. So almost 6 weeks ago. And 6 weeks is just the time needed for a Peregrine chick, which weighs around thirty grams when hatched, and is then covered in fine white down, to transform into the fastest bird in the world! We will therefore shortly witness a particularly important and moving stage: fledging. And the least we can say is that this is not without any risk. The young Peregrines which, since hatching, have been careful not to fall, will, from one day to the next, throw themselves into the void several tens of meters high! It is unknown what triggers this mechanism. Is it a hormonal signal? It's possible.
Ringing in Saint Gilles and Woluwe Saint Pierre
Two new broods of Peregrine falcons have been ringed in recent days.
The ULB Peregrine falcons have been ringed
The ULB Peregrine brood was ringed this Wednesday. The falcons are 3 weeks old, the ideal age to carry out the process of ringing.
Two male juvenile falcons in Uccle
The Peregrine brood at Saint Job church in Uccle consists of 2 males this spring.
Update on the Peregrines nesting in Brussels
The surveys are not finished and a surprise is always possible but here is the state of knowledge about the pairs of Peregrine falcons that nest in Brussels.
There will be no falcon chick this spring at the cathedral
The first signals of hatching at the cathedral have not been materialized. It was 1 May, we could clearly hear the chick chirping in the egg and we could see the first crack in the eggshell.
Four sisters at Saint Antoine
The family Peregrine falcons at the Saint Antoine church in Etterbeek has a clutch of 4 female chicks this spring. A brood with only males or only females is not common, hence not really exceptional. The Peregrine Falcon is monogamous, so the theory is that the number of males and females should be equal in the population. Difficult to say if this is the case in the overall population because it is really difficult to remotely determine the sex of the non-breeding falcons that we occasionally see here and there. But not the Peregrine chicks!
The egg chirps at the cathedral!
This spring, like the previous one, the female Peregrine who arrived at the cathedral in 2019, laid a single egg. It’s exceptional, except that… it’s the second time she lays a single egg.


On the Peregrines menu!
Peregrines are apex predators, meaning they are at the top of their food pyramid. They therefore have no or almost no predators themselves. They also have the particularity of being able to feed on a wide diversity of prey. These prey have one thing in common: they fly! So they are birds, and, from time to time, a bat. Peregrines are therefore aerial hunters, capable of seizing a White-fronted Goose (not a Toulouse Goose!) as well as a Blue tit. Obviously there are exceptions like this Peregrine photographed in Germany on a Wild Boar carrion or, closer to home, in Zaventem, this young female falcon who was feeding on the remains of a Wood Pigeon. But we will come back on this later.
Hatching at the ULB (part 2)
Wednesday April 24. As a reminder, a falcon chick hatched the evening before while we could hear eggs chirping loudly when the female went to get her first meal this morning at 8:24 a.m. It is now 10:45 a.m. and the female returns. The male, who had taken over brooding in the meantime, gets up revealing a chick barely out of the egg. A second falcon is therefore hatched under the male, which is rare. The female quickly covers the two chicks and the two cracked eggs (video 7).
Broadcast failure of the ULB images… while hatching!
The transmission system of the camera of the ULB nest broke down on Monday, hence, the hatching was expected that day. The connection could only be reestablished today. But fortunately, the recording system continued to work and... here are some images of the last few days!
Peregrine chicks in Saint Gilles and Etterbeek!
At the ULB we expect them to hatch any day now, but in Saint Gilles and Etterbeek, two constituent municipalities of Brussels, the falcon chicks already hatched.
Soon the eggs at the ULB will hatch!
The Peregrine pair which nest on the Solbosch campus, at the top of the bell tower of the historic building of the University of Brussels (ULB), has been there since 2019.
Uccle’s two falcons have hatched!
The hatching of the 2 eggs of the Uccle Peregrine pair was expected last Wednesday after 32 days of incubation. The first chirps were heard on Thursday. Hatching was therefore imminent but... we had to wait until Sunday morning to see the first chicks emerge from the shell on its own! The second falcon chick broke free from its shell this morning, shortly before dawn.
See them in real life!!
This year we are once again offering you the possibility of observing by screen (GSM, tablet, PC, TV) 3 families of Peregrine falcons via camera/server/encoder/streamer, systems installed by real specialists, there in the tower of a cathedral, there behind the clock of a church, there at the top of the belfry of the historic building of a prestigious university! Each time it is a technical challenge and... a significant budget. Because obviously, the installations in question have nothing comparable to the webcam of a computer which allows you to chat with Aunt Christine seated in her armchair at the other end of the street! A huge thanks therefore to the institutions which welcome us, and which finance all the expenses linked to the Falcons for All program!
Eggs are chirping in Uccle!
The first time a pair of Peregrines were nesting at the Saint Job church in Uccle dates from spring 2015. The male is ringed! Deciphering the code on his ring allows us to know that he was born in April 2012 in the Saint Rombaut cathedral in Mechelen. The distance between Mechelen and Uccle is 28 km.
They almost disappeared, the sequel
From 1955, many birds were found dead in agricultural areas of the British Isles. The relationship was then quickly established with the newcomers among persistent organic pollutants: aldrin and dieldrin belonging to the sad family of cycloidienes. These substances are powerful insecticides which are used in particular in the coating of seeds in order to protect them – preventively – from insects. The problem is that it turns out that in high doses, these products are... fatal, including for humans. This was observed on workers or farmers who had to handle large quantities of the product.
They almost disappeared!
The recent history of Peregrine Falcons is particularly eventful. How can we imagine that this bird, which today nests in the corners of Brussels, disappeared from Belgium between the end of the 1960s and 1994? What exactly happened?
A new spring of observation
A new spring but not just any spring! Exactly 20 years ago, a pair of Peregrine falcons settled in the center of Brussels, at the top of the north tower of the Cathedral of Saints Michael and Gudule.


A new season of observation coming soon
... a new season of observation coming soon