Classification and Range
The Laughing Kookaburra, Dacelo novaeguineae, is an Australian carnivorous bird in the kingfisher family. This species of kookaburra is well known for its laughing call. The laughing kookaburra was first described by French naturalist Johann Hermann in 1783, its specific epithet novaeguineae refers to New Guinea. It is found throughout eastern Australia, and has been introduced into the south-west corner of Western Australia, Tasmania, Flinders Island, Kangaroo Island.
Prefer open eucalyptus forests and woodland, riparian habitats along major watercourses. Kookaburra have adapted extremely well to modified or urbanized areas such as farmland, parks and gardens, and residential zones.
Laughing kookaburra are the largest of the kingfishers. Males have an average weight of 307g, while females are slightly larger at an average of 352g. Kookaburras are monomorphic (similar plumage between the sexes)and have a primarily whitish body (head and underparts);dark brown back and ear-coverts and a rufous-brown tail and rump with black barring. Variable amounts of blue feathering can be found on the rump and wing coverts. The upper mandible of their formidable bill is dark brown, contrasting with the upturned, pale-colored lower bill. In flight, the white bases of the primary feathers appear as a large spot on the outer wings. As with other members of the kingfisher family, kookaburra have relative short, weak legs which are effective for perching, but are not used for hunting prey.
Kookaburra are typically long-lived. Longevity in the wild is 111&fras1;2years. In captivity, longevity is often 20-30 years.
In the wild: Kookaburras are generalists and will eat anything they are able to swallow. Insects, arthropods and small reptiles, such as skinks, make up the majority of their diet. In some areas, mollusks, crustaceans, frogs and fish are also consumed. Although kookaburras are kingfishers, fish is not a major component of their diet, and some individuals may never have access to that source of food if their territory lacks a pond or stream. Small birds, mammals and snakes are taken less often. When living in close proximity to humans, kookaburras are well known to accept food scraps and other offerings and will readily come down to an occupied picnic table or kitchen window for hand-outs. Similar to birds of prey, indigestible components of the diet (hair, exoskeletons, etc.) are regurgitated in the form of a cast.
At the zoo: Hopper mice, crickets and mealworms. Mouse pinkies and extra bugs are offered in addition to the adult diet during chick-rearing.
In the wild, kookaburras nest from September through December (springtime in the southern hemisphere). Pairs are monogamous and mate for life. Kookaburras are highly social and often live in extended family groups composed of the adult breeding pair and offspring remaining in their natal territory as helpers (see Life Cycle below for more details). As spring approaches, pairs become more vocal, and the male begins offering courtship feedings to the female. This behavior reinforces the pair bond while ensuring the female is getting ample food prior to egg-laying. Concurrently, the pair begins inspecting and cleaning out their nest. Kookaburras most commonly nest in existing horizontal tree cavities located in large eucalyptus trees. Unlike woodpeckers, they are not capable of excavating new nest holes, thus making them reliant on the presence of natural cavities (i.e. from broken tree branches, fire scars, etc.) for nesting. Their weak legs and feet prevent them from nesting in vertical cavities since they are unable to climb up steep cavity walls like parrots. Nests can be located as low as ground level but are typically higher up (some recorded as high as 180 feet). When natural tree cavities are lacking in a territory, kookaburras have been known to nest in termite mounds, haystacks, or holes in a wall.
A clutch of 1-5 eggs can be laid, but 2-3 eggs is more common. A 24-48 hour interval between the 1st and 2nd egg is typical, and 17-96 hour intervals between subsequent eggs. Both the male and female (and helpers to a lesser extent) incubate the eggs which hatch after a 24-29 day incubation period. After hatching, the chicks are fed, brooded and defended by both sexes (and all members of a family group, if present). When food resources are limited, competition between chicks in the nest can be severe, often resulting in siblicide and the death of younger, weaker offspring. Asynchronous hatching of eggs contributes to this competition for food resources in the nest.
Chicks fledge at 32-40 days of age and are cared by the parents and helpers for an additional 6-8 weeks. Female offspring leave their natal territory at 1-2 years of age while males disperse at 2-4 years.
Laughing kookaburras are highly sedentary and territorial. The size of their territory is dependent upon the quality of the habitat and the presence of key features within that habitat. These features include: potential nesting hollows, roosting trees, and predictable food resources.
Kookaburras are cooperative breeders and form extended family groups comprised of close relatives- primarily offspring of various ages from previous years. Remaining young act as helpers and assist with raising subsequent broods and defending the family territory. Male offspring tend to act as helpers more than females and tend to remain with their parents longer before dispersing. Groups of 3 to 9 birds have been reported, but family size is highly dependent upon, and limited by, the quality of the territory's habitat and food resources. Within a family, the adult pair remains dominant over all offspring, and older offspring are dominant over all younger siblings. Helpers within a family are always recruited from a pair's offspring hatched in previous years, never from surrounding, unrelated groups. Territories are aggressively defended by the pair and helpers. Maintenance of territory boundaries is achieved primarily through the use of their distinctive, well-known laughing vocalizations. In the early morning and evening, group members gather in select portions of the territory to engage in a loud, raucous chorus to announce their presence to neighboring kookaburra families.
Young birds eventually disperse to fill vacancies in breeding pairs in surrounding territories. They do not disperse to act as helpers, however, since that role is reserved for birds that are directly related to a breeding pair.
Adults and fledglings are vulnerable to many sources of predation. Avian predators include large owls and diurnal raptors. Nestlings and incubating adults can be taken by pythons, goannas and quolls. Introduced fox and domestic cats are also significant predators. Collisions with vehicles can negatively impact kookaburras living in close proximity to humans. Although good-intentioned people may feed kookaburras table scraps and meat leftovers, adults and/or nestlings that are overfed on inappropriate (human) food may suffer from nutritional deficiencies or developmental abnormalities.
Location at the Zoo
The zoo has 3 pairs of Laughing kookaburra. One pair is on exhibit in Australasia, next to the Willawong Station. Two other pairs are off-exhibit for breeding purposes.
How You Can Help!
Preserve nest cavities; install artificial nest boxes in the absence of natural cavities; avoid using pesticides in your garden in order to protect beneficial, insectivorous animals in your yard. Visit the How You Can Help section for more tips.
Sources and Suggested Reading
el Hoyo, J., Elliott, A. & Sargatal, J. eds. (2001) Handbook of the Birds of the World. Vol.6. Mousebirds to Hornbills. Lynx Edicions, Barcelona.
Legge, S.(2004) Kookaburra: King of the Bush. Australian Natural History Series, CSIRO Publishing, Victoria, Australia.
Fry, C.H., Fry, K. & Harris, A. (1992). Kingfishers, Bee-eaters & Rollers. Princeton University Press, New Jersey.