Live from the kestrel box
Two successful broods in the last three years: A pair of kestrels now regularly raises its offspring on our Fassberg Campus. But what does such a breeding and rearing process look like? Thanks to our kestrel box with an integrated camera, we could follow our kestrel family live this year.
Built by our Carpentry and equipped with technology by our IT & Electronics Service, the new nesting box was ready for its tenants in mid-March. Not long after that, the pair of kestrels moved into the box high up on tower 6. This year’s brood was especially large – from each of the six eggs hatched a fluffy chick. Thanks to a built-in camera, we could follow the rearing of the little “gang” of six around the clock for the first time.
The kestrel camera will be running again next year. To bridge the gap, we have compiled the best moments from 2024 from over 900 hours of video footage. See how our kestrel pair moved into their home in the BioDiversum, hatched six eggs, and successfully raised the chicks.
Good to know:
1. Differentiate male / female: You can recognize the male kestrel by its light grey head and light grey tail feathers with a black terminal band. The female is reddish-brown with dark horizontal bands on the back and tail.
2. Egg deposition: Kestrels usually lay three to five (a maximum of seven) eggs at intervals of one to two days. Our female started laying eggs on April 15 and laid six eggs in total.
3. Incubation & hatching: The “actual” incubation – mainly by the female – only begins from the second last or last egg so that all the chicks hatch at the same time if possible. During incubation, the male supplies the female with food, such as mice. The young then hatch after around 27 to 29 days. Our first four chicks fought their way to freedom on Monday, May 20. The two "laggards" followed the days after.
4. Rearing: It is quite natural that not all chicks leave the nest. The smallest and weakest of the siblings usually find it difficult to assert themselves. Breeding success depends heavily on food supply and weather conditions. It can also happen that deceased chicks are fed to the remaining young – which sounds cruel but is normal and sensible for the parents given their costly food procurement. That increases the chances of survival for the remaining young. This year, however, all our chicks made it!
5. Moving out: After about four weeks of rearing, the young take their first flight exercises – they fledge and become more independent step by step over the following weeks until they are ready to hunt independently and look for their own territory. On June 20, the first of our young birds fledged; on June 24, the last laggard left the safe nest. The young falcons are no longer fed by their parents. Only sporadically do they visit the "parental home". In July / August, the family bond gradually dissolves and the offspring fly out into the big wide world.