The common starling is an invasive pest and a significant problem in both urban and agricultural areas.
With its iridescent colouration, on its own the common starling, Sturnus vulgaris, would be considered a very pretty bird. Alas, it can form large flocks causing widespread damage to crops and creating a significant nuisance in urban areas. It is considered one of the most invasive bird pests worldwide.
The starling is native to Europe and northern parts of Asia and has been introduced into North America, South Africa, Argentina, Polynesia, New Zealand and Australia. Its distribution in warmer climes seems limited by the availability of water. This also appears to be the case in Australia. Having been released on the eastern coast of Australia back in the 1860s (as a misguided attempt to reduce insect numbers in Australia!), it has spread up the east coast into the tropical north and around to South Australia. However, it is generally limited to two small populations in Munglinup and Condingup in Western Australia. Any individuals or small flocks that manage to cross the arid Nullarbor Plain are controlled by the Department of Agriculture and Food.
Starlings are small to medium sized birds with glossy black feathers and an iridescent green and purple sheen. After moulting, they can have a spotted appearance as the new feathers have pale tips. The males and females have a similar appearance. One distinguishing feature is that on the ground they tend to walk or run, rather than hop like many other birds.
Although they can breed at any time, spring is the main breeding period. In their natural environment they will pair off and build nests in tree hollows or holes in the ground or on cliffs. In the urban environment, the eaves and roofs of buildings are ideal nesting sites. They are prolific breeders capable of two to three broods a year each containing four to six eggs. With an incubation period of only 12 days and the young taking only 14 days to edge, starling numbers can increase rapidly. They can form massive flocks of up to 25,000 individuals.
Starlings are big insectivores – the reason the colonists introduced them for insect control – with invertebrates forming at least half of their daily food intake. However, they readily eat fruit, berries, vegetables and grain, which can make them a significant problem in the horticulture industry, during seeding of cereal crops and in areas where grain is stored. There is also concern regarding their role in a variety of diseases, such as Salmonella, Newcastle disease (in poultry) and transmissible gastroenteritis (in pigs) in animal husbandry areas.
Diseases are also a concern in urban areas where they roost as they can cause significant contamination and mess with their droppings as well as creating serious noise issues. Nesting in roof areas can cause significant problems with bird lice entering buildings.
Due to their large numbers, trapping or shooting are not viable options. Poisoning has been used in the USA with some success although it generally isn’t used in Australia. The use of sound as a scare tactic has been trialled with limited success, although efforts utilising bird distress calls have apparently proved more successful. As starlings are a widespread pest, elimination is not a feasible option, meaning management methods are best focused on exclusion. Netting fruit crops and exclusion from potential nesting sites, and from food and water sources, are the most effective strategies to mitigate damage.
Information on other bird pests.
