The cuckoo bird gets its name from its very distinctive call, which has inspired thousands of cuckoo clocks. However, their strange communication isn’t the only weird behavior this bird is known for. Some species of cuckoo birds are known as brood parasites. This article will teach you what a brood parasite is and explore some other animals that exhibit this behavior.

What is a brood parasite?

Through some sort of deception, a brood parasite relies on others to raise their young. This behavior has appeared in insects, fish and birds. By manipulating the parents of the same or another species, brood parasites abandon their own children, leaving them to be brought up by others.

Why do they do this?

By letting another set of parents raise their young, the brood parasite avoids the chore of having to gather more food than what it eats. It doesn’t have to build a larger, sturdier nest or work to defend its young. It can go on about the process of gathering its own food for survival and mating again, just to repeat the parasitic behavior.

What about the new parents?

Unfortunately, brood parasites sometimes destroy the eggs or young of the host parents when leaving their own behind. Cuckoos in particular are the worst; the young hatch earlier than other birds and summarily get rid of other baby birds in the nest at the first opportunity. Cuckoo birds aren’t discerning about the size of the host they leave their eggs with either. It is common to see two very tiny parents laboring mightily to feed a huge cuckoo chick.

Birds

Though there are only a few species of cuckoo that are known to be brood parasites, they are one of the most commonly studied. The cowbird is another species of bird that is known to be a brood parasite as well. Many parasitic birds have eggs that are similar in size, shape and color to the hosts they are known to use. The shells of the parasite birds are thicker and resist being rejected by the new host parents if they do detect that it is not theirs.  The brood parasite has to be careful; too many foreign eggs will alert the hosts that they aren’t their own and the whole nest may be rejected.

Fish

A species of catfish is known to be a brood parasite. This species is found in Lake Tanganyika, which is located in Africa. Known as a mouthbrooder, the catfish eggs are incubated in the host’s mouth rather than in a nest like a bird. The foreign eggs eat the hosts’ own eggs while incubating, taking over the entire parenting process.

A species of freshwater perch in Japan breeds by creating a nest in a patch of reeds. The male perch guards the nest while the females lay eggs. The parasite easily slips in and lays its own eggs, which are smaller and sturdier than the hosts are.

Insects

The cuckoo bee, named after the avian counterpart, is one insect that is known as a brood parasite. By laying their eggs in the nests of other bees, this species of bee is more commonly known as a kleptoparasite. That’s because the young bees that the cuckoo bee lays in the nest are almost never directly taken care of by the host bees. Instead, the cuckoo bee young take food and protect themselves.
True brood parasites are very rare in the insect world.

Bees aren’t the only insect species with brood parasite tendencies; some wasp species show the same types of behavior, laying their eggs in the nests of mud daubers and potters. Butterflies, bumble bees and some species of ants have shown brood parasite behavior as well.