Laughing kookaburras (Dacelo novaeguineae), famous for their distinctive cackling call, are native to eastern Australia, but have since been introduced into the south-west of the country, as well as Tasmania, and parts of New Zealand’s North Island.
According to the well-known kids’ nursery rhyme, kookaburras can be found sitting in gum trees, a common name for eucalyptus, but is this an accurate description of their preferred habitat?
Read on if you’re interested in finding out more about the nesting habits of laughing kookaburras and how they raise their young.
Kookaburras are cavity nesters and seek suitable hollows in which to lay their eggs. They appear unfazed by living in close proximity to humans, and their choice of nest sites reflects this, with backyard trees an increasingly popular site for nesting pairs to set up home.
Kookaburras are a species of kingfisher birds that are not known for their skills in constructing elaborate nests. Many kingfishers will simply dig out a basic burrow in a riverbank or cliffside and move in, without adding any finishing touches. Kookaburras are no exception.
Naturally occurring cavities in trees are used, without any additional lining or preparation. A termite’s mound in a tree may be burrowed into and upcycled into the perfectly shaped and positioned nest without too many modifications.
Laughing Kookaburra inside the nesting cavity
Kookaburras are cavity nesters, and will often make use of a natural hollow in a tree trunk, or will burrow into a termite’s nest that has been formed on the trunk or branches of a tree.
Their constructions are not particularly sophisticated or elaborate; where natural hollows are used, little extra preparation is needed to make them fit for habitation.
Cavities, whether located inside trees, dug into banks, or excavated into termites’ nests, feature a sizeable opening to allow adult birds to enter and exit comfortably.
Kookaburra with nest built in a Termites nest
The internal chamber of kookaburra’s nest hollow needs to offer a vast space in which to raise what quickly grow to become reasonably large chicks, and is usually between 20 and 150 cm (8 to 60 in) wide and 20 to 40 cm (8 to 16 in) high. The opening to the nest cavity usually measures between 12 and 15 cm (5 to 6 in) across, but can be anything from 8 to 40 cm (3 to 16 in) wide.
A kookaburra pair begins preparing their nest site in late August, ahead of the first clutch of eggs being laid any time from September onwards. Usually by November, or occasionally later into December, the latest-born young will have fledged.
Kookaburra spreading its wings outside of the nest
Incubation of a kookaburra’s eggs takes on average between 24 and 26 days. Nesting begins shortly before the first eggs are laid. Fledglings are ready to leave the nest after 32 to 40 days, but extended family groups remain together long after the young can independently feed themselves.
Frequently, kookaburras will take advantage of a naturally occurring hollow in a tree trunk. Little effort is made to prepare or line the nest cavity before eggs are laid.
On other occasions, male and female kookaburras will work together to excavate a burrow-like cavity in a nest built by termites in the branches of a tree, or dig out a hole in a bank or cliff.
Termite mounds on the side of trees are the perfect size to offer almost ready-made nesting solutions for kookaburras, as they can be adapted for habitation with only minor modifications needed.
Kookaburra checking out a potential nesting cavity in a tree hollow
Young kookaburras are ready to fledge between 32 and 40 days after hatching. Family units remain closely bonded, occupying the same territory, and with younger unpaired birds assisting with nesting duties, including taking turns to incubate eggs and bringing food for hungry hatchlings.
Juvenile kookaburras continue to be fed by parents and ‘helper’ birds for a further 6 to 10 weeks.
It’s most common for a pair of kookaburras to raise a single brood in a breeding season, although it is not unheard of for a second, subsequent brood to be raised successfully. If one clutch fails, then another brood will often be attempted.
The average number of eggs per clutch is 2 or 3, but up to 5 may be laid. In clutches with more than two eggs, the first birds to hatch may gang up on the youngest, weakest hatchling and harass it with pecking and jostling until it dies, or prevent it from feeding so it starves to death.
Kookaburra chick (right) begging for food
It is claimed that kookaburras show a high level of fidelity to nest sites they have previously successfully raised young in. Evidence shows nests are reused year after year, sometimes for five or more years in a row. In one documented case, a nest cavity was used on and off over the course of 60 years.
As they are non-migratory birds, kookaburras remain in their territories all year round, and live in close social groups.
Family members continue to play a role in raising young, and if a pair of kookaburras has found a spot that has proved to be suitable for a past brood, then it’s likely that they will continue to make use of the same site in future seasons.
A pair of Laughing Kookaburras (Dacelo novaeguineae) making their nest in a termite mound
Kookaburra eggs are white and rounded, measuring around 36 by 45 mm (1.4 by 1.8 in).
Eggs are usually laid between September and December, and one clutch in a season is the norm, although a second clutch may also successfully be raised.
Pair of Kookaburras perched on a tree branch together
If they sense any form of threat or disturbance, kookaburras are likely to abandon their nests or young. If you have a nest box in your yard that is being used by kookaburras, resist the temptation to look inside, as the interference may cause the adults to abandon any young they may be raising inside.
Threats to kookaburra nests include other bird species, tree-climbing snakes, and goannas.
Backyards are popular choices for nesting kookaburras to set up home. They seek spots with plenty of tree cover for natural shelter, access to fresh water, and plenty of potential perching sites, such as branches and high fences. Planting native shrubbery will attract lizards and insects commonly eaten by kookaburras.
Purpose-built nest boxes with wide openings may be used by kookaburras, and according to research, around 9 percent of recorded kookaburra nests were built in artificial boxes.
Around 60 percent of kookaburra nests are constructed in hollows in living eucalyptus trees, with. Cavities in other tree species account for a further 8 percent of kookaburra nests, while dead trees and tree stumps were used as the nest site for another 7 percent of breeding kookaburras.
An adult kookaburra perches on the edge of a tree hollow preparing to feed his chicks, Victoria, Australia
Kookaburras are tree-dwelling birds, and seek cavity nests in the trunks or rotten branches of a tree. Nest site height varies significantly, with the lowest nests built around 20 cm (7.9 in) off the ground, while the highest examples can reach up to 60 m (197 ft). Occasionally they will also make use of the nest construction built by arboreal termites, found attached to branches or trunk of a tree.
Interestingly, although male and female kookaburra pairs share incubating duties, they also frequently rely on the presence of a ‘helper’ bird – often a younger bird from the family group that has not yet mated – to take on a significant role in keeping eggs warm and gathering food for the young once they have hatched.
Overnight brooding is undertaken by the female, but the male and other family members take turns during the day to help out.
Kookaburras are highly social birds and live, forage, and raise young in communal family groups. Nighttime roosting is also a communal activity, with birds gathering together as night falls to head to a roosting spot in the high branches of a tree where they spend around 12 hours huddled together to conserve body heat. Once they have identified a safe overnight roosting spot, they tend to habitually return to it, night after night.
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