Brolga facts for kids
The brolga (Antigone rubicunda) is a large bird from the crane family. It was once called the "native companion" and is also known as the "Australian crane." This name was given by a famous bird expert, John Gould, in 1865.
Brolgas are common birds that live in groups. They are found in wetlands across tropical and south-eastern Australia and New Guinea. These birds are tall and stand upright. They have a small head, a long beak, a thin neck, and long legs. Their feathers are mostly grey, with black tips on their wings. They have a bright orange-red band of colour on their head.
Brolgas are famous for their special mating dance, which is well-known in Australia. They build their nests from wetland plants, either on raised ground or floating on shallow water. Usually, they lay two eggs. The eggs hatch after 32 days, and the young birds can move around very soon after hatching. Brolgas eat both plants and small animals.
Even though brolgas are not considered endangered in most places, their numbers are slowly decreasing, especially in southern Australia. People are working to protect them in some areas. The brolga has been on the Queensland coat of arms since 1977. It was officially made the state bird emblem in 1986.
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Understanding the Brolga: Its Name and Family
When the brolga was first described by a scientist named George Perry in 1810, it was mistakenly grouped with herons and egrets. However, the brolga is actually part of the Gruiformes group, which includes crakes, rails, and cranes. It belongs to the genus Antigone.
The bird expert John Gould called it Grus australasianus. He noted that it was common in northern and eastern Australia. He also found that it was easy to tame. The Royal Australasian Ornithologists Union officially named the bird "brolga" in 1926. This name comes from the Gamilaraay word burralga.
In 1976, scientists noticed that the brolga, the sarus crane, and the white-naped crane seemed to be related because their calls sounded similar. Later, studies of their DNA confirmed this. These studies also showed that the brolga is more closely related to the white-naped crane, even though it looks more like the sarus crane.
The brolga used to be in the genus Grus. But in 2010, new studies showed that this group needed to be changed. So, the brolga and three other crane species were moved into the genus Antigone, which was first named by Ludwig Reichenbach in 1853.
Scientists once thought there might be two types (subspecies) of brolgas. However, studies of their DNA have shown that they are all part of one group.
What Does a Brolga Look Like?
The brolga is a very tall bird with a large beak, a long, thin neck, and long, stilt-like legs. Males and females look very similar, but females are usually a bit smaller.
Adult brolgas have a grey-green, featherless area on their head. Their face, cheeks, and throat pouch are also bare and are a coral red colour. Other parts of their head are olive green with dark, stiff feathers. The throat pouch, which hangs down more on adult males, looks almost black because of these dense, stiff feathers.
Their beak is greyish-green, long, and slender. Their eyes are yellowish-orange. The small feathers covering their ears look like a grey patch surrounded by the red bare skin. The rest of their body feathers are silvery-grey. The feathers on their back and wings have pale edges. The main wing feathers are black, and the secondary ones are grey. Their legs and feet are greyish-black.
Young brolgas do not have the red band on their head. Their heads are fully feathered, and their eyes are dark.
A full-grown brolga can be between 0.7 to 1.4 metres (2.3 to 4.6 feet) tall. Their wingspan can reach 1.7 to 2.4 metres (5.6 to 7.9 feet). Adult males weigh about 6.8 kilograms (15 pounds) on average, while females average 5.66 kilograms (12.5 pounds). Their weight can range from 3.6 to 8.7 kilograms (7.9 to 19.2 pounds). Some very tall males have been reported up to 1.8 metres (5.9 feet) tall. The brolga is considered the heaviest flying bird regularly found in mainland Australia.
It's easy to confuse the brolga with the sarus crane. However, the sarus crane's red head colour extends down its neck, while the brolga's red is only on its head. Brolgas are also more silvery-grey, have blackish legs (not pink), and make lower-pitched calls. Also, in Australia, sarus cranes are only found in the north-east, while brolgas are more widespread.
Where Do Brolgas Live?
Brolgas are found across northern and north-eastern Australia, especially in north-east Queensland. They are also common as far south as Victoria. You can also find them in southern New Guinea. Sometimes, they are seen rarely in New Zealand and western Australia.
In northern Australia, there are an estimated 20,000 to 100,000 brolgas. In southern Australia, there are about 1,000 birds. The number in New Guinea is not known. Before 1961, people thought the brolga was the only crane species in Australia. Then, the sarus crane was also found in Queensland.
We don't fully understand how brolgas move around Australia. However, large groups are seen regularly in eastern Queensland in areas where they don't breed. Some populations near the coast are thought to move up to 500 kilometres (310 miles) inland. We know little about the movements and homes of the brolgas in New Guinea.
In Victoria and New South Wales, rain falls more evenly throughout the year. The driest time is from December to May. During this period, southern brolga groups gather in inland areas. These places include marshes, edges of reservoirs and lakes, pastures, and farms. When rain comes in June and July, they spread out to coastal freshwater marshes, shallow lakes, and other wetlands where they breed.
Queensland has the largest number of brolgas. Sometimes, flocks of over 1,000 birds are seen there. The brolga is Queensland's official bird emblem and is on its coat of arms. Breeding pairs and groups are found across several floodplains along the Gulf of Carpentaria. Brolgas prefer grassland areas, but they also share some Eucalyptus woodlands with sarus cranes. More brolgas are found in floodplains with lots of grassland.
How Brolgas Live and Behave
Brolgas live in social groups similar to sarus cranes. In breeding areas, pairs protect their territory from other brolgas. If they successfully raise chicks, they stay in their territory with one or two young birds. Non-breeding birds, including young birds from past years and adults without breeding territories, are also found in these areas.
When it's not breeding season, brolgas gather in large flocks. These flocks seem to be made up of many smaller family groups rather than one big group. Within the flock, families sometimes stay separate and do things together as a family, rather than with the whole flock.
When brolgas take off from the ground, their flight can look a bit clumsy, with lots of wing flapping. You can see their black wingtips when they are in the air. Once they gain speed, their flight becomes much smoother. They often fly very high, circling in large loops, sometimes making their loud, rough call.
What Do Brolgas Eat?
Brolgas are omnivores, meaning they eat both plants and animals. They search for food in wetlands, saltwater marshes, and farmlands. They use their strong beaks to dig into the ground to find bulbs and roots.
Brolgas in northern areas have a very varied diet. They eat shoots and leaves of wetland and upland plants, cereal grains, seeds, insects, mollusks, crustaceans, frogs, and lizards. In saltwater marshes, they can drink salty water because they have special glands near their eyes that help them get rid of extra salt. Studies of their feathers show that their diet is very diverse, with plants making up only a small part of it.
Mating and Raising Young
Brolgas are monogamous, meaning they usually stay with the same partner for life. However, if one bird dies, the other may find a new mate. A special sign of a bonded pair is their synchronized calling, which the female usually starts. She stands with her wings folded and beak pointing to the sky, making a series of trumpeting calls. The male stands beside her in a similar pose, but with his wings spread out and primary feathers hanging down. This is the only time you can reliably tell the male and female apart. The male makes one long call for every two calls from the female.
Brolgas are famous for their detailed and ritualized mating dances. The dance starts with a bird picking up some grass and tossing it into the air, then catching it with its beak. The bird then jumps about a metre (yard) into the air with its wings spread. It continues by stretching its neck, bowing, strutting around, calling, and bobbing its head up and down. Sometimes, only one brolga dances for its mate. Often, they dance in pairs. Sometimes, a whole group of about a dozen brolgas dance together, lining up opposite each other before they begin.
Brolgas breed throughout their range in Australia and New Guinea. The start of their breeding season depends more on rainfall than on the time of year. So, in areas with monsoons, the season is from February to May after the rainy season. In southern Australia, it's from September to December.
The nest is built by both the male and female. It's a raised mound of pulled-up grass and other plant material. It's usually placed on a small island in shallow water, or sometimes it floats. Occasionally, the birds make very little nest, use an old swan nest, or just lay their eggs on bare ground.
Brolgas usually have one group of chicks per year. They typically lay two eggs, but sometimes one or three. The eggs are dull white with scattered reddish-brown spots, which are thicker at the larger end. They measure about 95 by 61 millimetres (3.7 by 2.4 inches). Both parents take turns sitting on the eggs, with the female usually on the nest at night. The eggs hatch after about 32 days.
Newly hatched chicks are covered with grey down and weigh about 100 grams (3.5 ounces). They can leave the nest within a day or two. Both parents feed and protect the young. The chicks grow their flight feathers within 4–5 weeks and are fully feathered within 3 months. They can fly about 2 weeks after that. If they feel threatened, they hide and stay quiet, while the parents pretend to have a broken wing to distract any danger. The adults continue to protect their young for up to 11 months, or even for nearly 2 years if they don't breed again.
Breeding pairs keep their own territories where they raise their chicks. In Victoria, these territories can be between 70 and 523 hectares (173 to 1,292 acres) in size. Each territory has a mix of farmland and wetlands. Families sleep in wetlands at night and move about 442 metres (1,450 feet) to and from these sleeping spots. Each family uses several wetlands within their territory. About 59% of breeding pairs in the Gilbert River basin and 46% in the Flinders River basin successfully raised at least one chick. About 33% of these successful pairs raised two chicks each.
Protecting the Brolga
The IUCN Red List of Threatened Species lists the brolga as being of "least concern". This is because it lives in a large area and has a population of more than 10,000 birds. Even though the population might be slowly decreasing, it's not declining fast enough to be in a more serious category.
Brolgas are not listed as threatened under Australia's Environment Protection and Biodiversity Conservation Act 1999. However, their conservation status can be different in each Australian state. For example, in Victoria, the brolga is listed as threatened under the Flora and Fauna Guarantee Act (1988). An action plan has been created to help this species recover and manage its future. It is also listed as vulnerable in Victoria's 2007 list of threatened animals.
The main dangers to brolgas, especially in southern Australia, include:
- Habitat destruction: This means their homes are being destroyed, especially by the spread of blue gum trees into breeding areas.
- Draining of wetlands: Wetlands, where they live, are being dried out.
- Collisions with powerlines: They can fly into powerlines.
- Changes in burning and grazing: How land is burned or grazed can affect their habitat.
- Spread of invasive species: New plants or animals can harm their environment.
- Harvesting of eggs: People sometimes take their eggs.
In the north-eastern part of their range, brolgas are safer. The floodplains of Queensland are mostly not suitable for farming, and much of the land is privately owned. However, new developments that change or reduce their habitat, especially in the Gulf Plains, could still affect their populations. Wind farms are also a new concern. Research shows it's important to build wind turbines away from wetlands that brolgas use for sleeping at night.
Efforts to protect brolgas include working with other countries, legal protection, research, monitoring their numbers, managing their habitats, educating people, and keeping captive flocks for breeding and reintroduction. While brolgas breed well in the wild, breeding them in captivity has been much harder.
See also
In Spanish: Grulla brolga para niños
