Watching three young storks spread their wings in a nest in Prekmurje, I was enjoying what looked like a cheerful family scene. Then our hotel’s owner told us that storks sometimes kill their own chicks. It was an unsettling thing to hear while looking at those three birds, and it raised a question that stayed with me: why do storks kill their young?
Our trip had brought us to northeastern Slovenia, where we had plenty of time to watch the birds. At the hotel, a live camera showed what was happening in a nest on top of a chimney. The three youngsters spread their wings and jumped, looking to us as though each wanted to put on the biggest show. When the parents returned with food, their attention quickly shifted to the meal. These were the moments we saw for ourselves; the account of chicks being killed came from our conversation with the owner.
Why Storks Kill Their Young
White storks sometimes kill one of their chicks, a behavior called parental infanticide. It is one way a brood can become smaller, known as brood reduction. Food supply and the demands of raising the young help explain this behavior: eliminating a weak chick can leave more resources for the others. DOPPS, BirdLife Slovenia, describes weakened chicks being thrown from the nest when food is scarce.
The explanation we heard at the hotel put the responsibility on the mother. Research gives a more precise picture. In a three-year study of 63 white stork nests, Francisco S. Tortosa and Tomás Redondo recorded parental infanticide in nine nests. The male killed the chick in eight of those nine cases. The victims were the smallest, last-hatched chicks, which had been growing more slowly than their nestmates. Those figures describe that study, not a rule for every stork family.
It is tempting to describe this as a parent predicting a bad year or sparing a chick future suffering. Those are human explanations of intention, and the evidence cited here does not establish them. The useful distinction is between observing a behavior and deciding what an animal must be thinking. Nor does the research mean that every pair kills a chick or that every chick lost from a nest was deliberately killed.
Do Young Storks Inherit Their Parents’ Nest?
The owner also told us that the first youngster strong enough to fly would inherit the nest. It was a memorable story, though I would no longer present it as an established fact. Research on white stork nest-site fidelity shows that breeding adults often reuse a nest, with age and previous breeding success influencing whether they return. Repeated occupation does not demonstrate that the first chick to fly takes ownership. Watching a youngster exercise its wings cannot tell us who will breed there in a later season.
Watching Storks in Prekmurje
White storks nest on rooftops, chimneys, poles, and purpose-built platforms, so a village can provide opportunities to observe them. Our wider Prekmurje travel story follows the landscape and experiences around this part of Slovenia. Here, the nest camera added something useful: a view into the birds’ daily activity without having to approach the nest. For photography, keep your distance and give the adults a clear route to their young.
What Stayed with Me
I still find storks imposing and a little mysterious. The three youngsters stretching their wings remain the clearest memory of that nest. Learning about parental infanticide made the scene harder to look at innocently, and it also exposed how readily I had supplied the birds with human motives. I can be troubled by what happens in a nest without claiming to understand a parent’s thoughts. That leaves plenty to observe, and a good reason to keep asking questions.
Frequently Asked Questions
Why do storks throw their babies out of the nest?
White storks can remove and kill weakened chicks as part of brood reduction. When food is limited, reducing the brood can improve the remaining chicks’ access to resources. This does not happen in every nest.
Is it always the mother stork that kills a chick?
No. A three-year study by Tortosa and Redondo recorded nine cases of parental infanticide in white storks, eight carried out by males. These observations do not establish a universal pattern for all populations.
Do the strongest young storks inherit the nest?
There is no basis in the research cited here for a rule that the first youngster to fly inherits its birth nest. Studies of nest reuse concern returning breeding adults and factors such as age and earlier breeding success.
Sources
Parental infanticide: Tortosa and Redondo (1992)
Motives for Parental Infanticide in White Storks Ciconia ciconia, Ornis Scandinavica, 23, 185–189. The primary study behind the nest counts and observations of male parents described above.
White stork behavior and nesting in Slovenia: DOPPS
DOPPS: Štorklje. BirdLife Slovenia’s account of white stork nesting sites and the removal of weakened chicks when food is scarce.
Nest reuse: Bialas and colleagues (2023)
Age, brood fate, and territory quality affect nest-site fidelity in white stork Ciconia ciconia, Frontiers in Zoology, 20, article 33. Research distinguishing adult nest-site fidelity from the inheritance story we heard.
You might also like
