The Torresian crow (Corvus orru) is a native Australian bird and is protected under State Wildlife Legislation (Nature Conservation Act 1992).
The crow plays an important role in natural pest management. They prey on insects and grubs, small rats and mice in grassland and woodland habitats and urban gardens. Crows also remove road-killed animals by feeding on carrion, and disperse many native vegetation seeds through defecation. The long-term conservation of this species is necessary for maintaining biodiversity.
It is a serious offence to harm crows.
Crows have solid black plumage with a green or purple shine and white underdown. They:
- have black bills and feet
- have a ring around the iris of the eye that changes colour with age, from blue (nestlings), to brown (from three and six months of age), to mottled hazel (from six to nine months of age), to white (for adult birds over two years of age)
- feed mainly on the ground
- hop-walk when preparing to take flight.
Torresian crows are very common in woodland and urban areas and have adapted well to areas where humans live.
Torresian crows breed between August and February and form monogamous breeding pairs that maintain a permanent territory. Both parents build the bowl shaped nest out of sticks lined with grass. Nests are located high in trees (over 10 metres) or on an artificial structure i.e. power poles. Clutches consist of four to five bluish, spotted eggs. Feeding duties are shared by parents. Young usually fledge within five to seven weeks but remain with their parents for up to three months before dispersing.
Problems caused by crows
Crow numbers can increase unnaturally due to the availability of food scraps at parks, public areas and industrial waste bins. They may become dependant on artificial sources of food and can be very noisy; therefore, they can be a nuisance to local residents.
The cawing call of the crow can be very loud. The main concern in urban areas is the noise and they may swoop to protect their nest, especially during the breeding season from August to February.
What Council is doing
Brisbane City Council has adopted ‘working towards a natural balance’ as the principle in controlling the crow population.
One way to achieve this is to restrict the artificial food supplies to crows to control their numbers to a natural level. Council is:
- installing covered bird-proof litter bins throughout the city
- providing information about wildlife and pest animals through brochures and community events.
Council does not remove crows from one location to another. Relocating birds simply shifts the problem to another location, can lead to aggression, and is rarely successful. If removed, new populations of crows will recolonise quickly.
What you can do
- do not feed crows or leave scraps of food or rubbish lying around. Ensure that garbage bin lids are kept closed, particularly industrial waste bins
- remove water sources and pet food from the backyard
- be aware of the breeding season of crows, and expect more noise between August and February, while the birds nest and raise their young
- do not try to kill or cause injury to the birds
- do not remove nests or eggs
- do not disturb the birds when there are fledglings in the nest.
Ensure your interactions with the crows are friendly in the use of your voice and body language (provocative or threatening behaviour can make the situation worse).
If noise is an issue, consider window treatments such as double-glazing, particularly in bedrooms, to minimise outside noise.
Find out more about crows swooping to protect their nest. Alternatively, to find out more information about crows, phone Council on 07 3403 8888 or view information from the Queensland Department of Environment and Heritage Protection's website.