White Stork: Why Do They Kill Their Young

Everyone knows the adage of storks gently delivering crying babies in their beaks to families ready to have a child. It is a simple way of teaching young children where babies come from without getting into the biological and anatomical details of human reproduction.

However, storks are not as wholesome as they appear in our stories. Videos of these radiant birds murdering their offspring have recently been posted online.

What would drive storks to do such a horrible crime? Why are these birds associated with giving a family a newborn baby if they are killing their own? Are other birds this twisted, or are white storks the odd ones out?

Like all stories and fables, there is a long history behind this imagery.

Basics on White Storks

Ciconia ciconia, the white stork, is one of the most well-recognized birds in the animal kingdom, right after owls, hawks, or eagles. Storks are prominent throughout several stories and admired for their gleaming white feathers and black trim. Their long legs and beak elevate them above the grass and the black lining around their eyes gives them a sense of mystery and intrigue.

They live across Europe, Asia, and Africa, migrating between the countries at the end of summer. White storks feed on an assortment of insects, small mammals, bird eggs, fish, crustaceans, and amphibians. They do not have many natural predators outside of habitat loss due to human activity. However, raccoons, skunks, and other birds poach their eggs when the nest is unprotected.  

White Stork Reproduction

Storks are one of a handful of birds that mate and guard the nest together. When a stork reaches three to five years old, they will find a suitable mate and build a nest of large sticks in tall trees or on rooftops. One of the storks will signal the nest is complete by adding a small leaf hanging over the edge.

Females lay a clutch of two to four eggs, which will hatch after 33 days. Both parents tend to the hatchlings for 58-64 days before the fledglings leave the nest. Some hatchlings will return to the nest for another few weeks before becoming independent.

By the end of summer, storks migrate to warmer weather and return to their nest in the spring. A pair of storks use the same nest for several years before building a new one.

Why Do Storks Kill Their Young

From the outside, white storks sound like very caring and loving parents. However, white storks perform infanticide more often than other birds. Infanticide is the killing of an infant or child within one year of age.

A three-year study in 1992 observed several white storks practicing infanticide. The results indicated that nine of 63 couples performed infanticide of the smallest, weakest, first hatched, or last hatched. Also, the males performed the task eight out of nine times.

White storks perform infanticide for the following reasons:

Survival of the Most Likely

When storks are tending to their young, they may notice one of the hatchlings isn’t growing or developing as quickly as the others. The eggs hatch at various times, but the storks know time is of the essence to avoid predators and prepare to migrate. If they notice one infant seems too weak, they will drop it from the nest to kill it early rather than having it become prey later.

Shortage of Food

Both parents must be constantly hunting for food to feed themselves and their young. When there is not enough food to feed all their young, the father will select the smallest hatchling and drop it from the nest to allow the others more food. This method reduces the number of mouths to feed and increases the chance the remaining hatchlings will survive.

Higher Nesting Maintenance

Stork parents perform internal calculations regarding a benefit-to-cost ratio regarding how much energy to use when raising hatchlings. Larger nests with four or five hatchlings require more time, energy, and resources than a nest with two or three babies. The longer it takes to care for the hatchlings, the more energy the parents lose. To save themselves energy and limited resources, they may remove a hatchling to make the brood easier to parent.

Do Other Birds Perform Infanticide

Surprisingly, white storks are not the only animals capable of performing infanticide. Records show many birds attack or kill their offspring for a multitude of reasons such as limited resources or removing a rival’s brood.

Examples of bird infanticide are:

• Bald eagle males kill their youngest and weakest hatchlings to manage resources, sometimes in a cannibalistic way to feed the other hatchlings when food is scarce.
• Cowbirds and cuckoos find another bird’s nest, remove the resident eggs, and lay their own eggs as a replacement. The cowbird or cuckoo leaves, letting the other bird roost and raise the infants in a forced adoption process.

Why Are White Storks Linked to Delivering Babies

It seems very ironic that a bird capable of killing its offspring is associated with delivering babies to a welcoming family. The idea of storks delivering babies is a symbolic image of good luck and coincidental timing.

Coincidental Timing

Around 600 years ago, human couples married during the summer. Summer is associated with fertility because of the Sun, warmth, and ability to raise crops to last through winter. Ideally, couples consummate their union around the same time white storks leave for their annual migration.

White storks returned to the European region nine months later in the spring to build a nest and lay their eggs. At the same time, pregnant mothers began giving birth. Human creativity and symbology linked the events together to associate white storks with babies about to be born.

Fairy Tales

Cassic fables like The Storks by Hans Christian Andersen created beautiful stories parents could share with their children. The fable tells of storks plucking dreaming infants from ponds and lakes to deliver them to good families. Consequently, families who misbehaved were given dead infants on their doorstep.

Parental Censorship

As children grow up, they often ask questions about the world around them. Naturally, when a child suddenly sees an infant come out of practically nowhere, they will ask how and where it came from.

At the time, sex and reproduction were not topics of discussion for civilized society. To avoid the vulgar details of human biology and anatomy, parents used white storks as a metaphor to explain where babies came from.

Collective Unconscious

Over time, other stories and children’s books depicted storks as delivering babies, and it became common knowledge to associate white storks with babies. Parents did not question why storks were related to babies or how these birds treated their own offspring. Humanity accepted the metaphor and recited it to future generations.

Storks are not evil birds for killing their young, nor are they bad parents. They are simply trying to raise their infants the best they can, with the harsh reality that nature is a cruel place. After weighing the overall benefits and costs, white storks will sacrifice a young and underdeveloped hatchling if it means the survival of the nest. 

The photo featured at the top of this post is © MikeDotta/Shutterstock.com