If you know much about cuckoos, you probably know they have a reputation for being really bad parents. But where does this reputation come from? Where do cuckoos lay their eggs, and why have they gotten such a bad reputation for it? Read on to find out more about cuckoos and their strange parenting habits.
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Do Cuckoo Birds Build Nests?
There are about 140 species of bird in the Cuculidae family, which the cuckoo birds belong to. About 40 percent of these birds are known as brood parasites and, as such, they don’t build their own nests.
Why Don’t Cuckoos Build Nests?
Many cuckoos don’t raise their own young. Instead, they lay their eggs in the existing nests of other bird species, leaving those birds to feed and care for the young cuckoo chicks.
Since these cuckoos don’t incubate their own eggs or raise their own chicks, they have no need for building nests.
That said, not all cuckoos are considered brood parasites. According to Stanford University, more than half of cuckoos throughout the world do build nests and care for their own young.
Why Do Cuckoos Lay Their Eggs in Other Nests?
Laying eggs in other birds’ nests is the defining characteristic of brood parasitism. Since many cuckoos are brood parasites, they come by this behavior quite naturally.
What isn’t clear is why some cuckoos are brood parasites while others are not, though It could be largely based on species.
Some specific species of cuckoo, such as the common cuckoo and the European cuckoo, are known for their brood parasitic activities. These cuckoos almost always lay eggs in other birds’ nests and don’t bother to make their own nests.
Other species, such as the black-billed and North American yellow-billed cuckoos, hardly ever lay eggs in other birds’ nests. They usually make their own nests and raise their own chicks.
Hereditary factors may also play a role.
For example, if a hen cuckoo was raised by host parents of another species, she will probably be a brood parasite and lay her eggs in another bird’s nest. If she was raised by her own parents, she may build a nest and raise her own young.
Do All Cuckoos Lay Eggs in Other Birds’ Nests?
As noted above, only about 40 percent of the world’s cuckoos are brood parasites; the other 60 percent build their own nests and raise their own chicks.
That said, 40 percent is a large number, considering that only about 1 percent of all of the world’s birds are considered brood parasites. This behavior is common among some species of ducks, cowbirds, and other birds, but is rarely seen in such a large portion of a single species.
For this reason, many people believe that all cuckoos lay their eggs in other birds’ nests. It’s a common misconception, since there are actually more cuckoos that are not brood parasites than ones that are.
What Bird’s Nests Do Cuckoos Lay Their Eggs In?
At least a hundred different cuckoo host species have been identified. Some of the most common host birds are reed warblers, pipits, dunnocks, and magpies, but cuckoos in a particular region may have their own favorite host species depending on what’s available.
Cuckoos tend to choose nests with eggs that look similar to their own. Not all cuckoo eggs look alike; some produce white or tan speckled eggs, while others produce blue eggs.
Cuckoos may also choose the same kind of nest they were raised in. If a particular cuckoo grew up in a magpie’s nest, she may be more likely to lay her own eggs in a magpie’s nest.
How Many Eggs Do Cuckoos Lay?
Cuckoos have to lay a lot of eggs because many of them won’t survive long enough to hatch. Many times, smarter birds will recognize the cuckoo’s egg next to their own and will push the “intruder” out of the nest.
Cuckoos generally lay only one egg per nest but may lay up to 50 eggs throughout the course of a single breeding season.
Sometimes, in an effort to protect her own egg, the intruding cuckoo will push one or all of the other eggs out of the nest. The host bird is more likely to accept the cuckoo egg if her own eggs are gone, or if there is the same number of eggs in the nest after the cuckoo’s visit.
What Happens When a Cuckoo Hatches in Another Bird’s Nest?
When a baby cuckoo hatches in a host nest, it takes over the place.
The baby instinctively pushes up against other babies or eggs in the nest, which are usually quite a bit smaller. The cuckoo chick will then push the other babies or eggs over the side of the nest, ensuring it will receive all the attention from the host parent.
Check out the video of this phenomenon below:
Rarely, cuckoo babies will coexist with other chicks in the nest, but this usually only happens if they are too big for the cuckoo to push over the edge.
The host bird will feed and care for the cuckoo baby as if it were her own. Often, the cuckoo babies grow much larger than the host birds, nearly outgrowing the nest before it’s ready to fledge.
Host parents may struggle to keep up with the baby cuckoo’s voracious appetite, especially as it grows and nears fledging time.
Cuckoo chicks will fledge within a few weeks but usually hang around the nest for a while longer, continuing to be fed.
Some cuckoos build nests for laying their eggs, but a little less than half of all cuckoos lay eggs in the nests of other birds. These cuckoos are known as brood parasites.
They will often lay their eggs in the nests of warblers, pipits, and other smaller birds. Usually, the baby cuckoo will push other eggs or baby birds out of the nest so they don’t have to share food and space.