Council has looked into this issue about how to lessen the impact of the Corellas within the township, and also the damage being caused to the trees, particularly within the past 7 years. I have included a summary of our findings below but it is worth noting in particular:
- Corellas are a riverine species, and as Winchelsea has the Barwon River running through the township, Corellas will always be a visitor to the region. There are many other ‘problem’ areas along rivers throughout Victoria as well as in other parts of Australia (especially South Australia)
- Native wildlife, including Corellas, are the responsibility of the State Government, namely the Department of Environment, Land, Water & Planning (DELWP). Read more
DELWP produced “Guidelines for Reducing Cockatoo Damage – Wildlife Management Methods” (PDF) which sets out the legal and policy framework in place for the protection, conservation and management of these birds in Victoria as well as providing some practical tips and management methods.
The situation in Winchelsea is regularly discussed with Wildlife officers from DELWP. Council also appointed a wildlife expert, Ian Temby, to visit Winchelsea and report back on any possible actions in 2016/17. Possible management actions are limited within a township area due to both EPA noise guidelines and Victoria Police regulations. Council officers will continue to look for any promising and effective measures to protect the trees within the township.
DELWP is currently developing a strategy specifically for Corellas. Below is a summary of the local research by Ian Temby and also information from the DELWP guidelines:
Cockatoos in Winchelsea
- The most common species of cockatoos present in Winchelsea are the Long-billed Corella, Little Corella, Sulphur-crested Cockatoos and Galahs.
- The Barwon River with its remnant River Red Gums and other vegetation provides a water source and roosting sites for the cockatoos.
- The surrounding landscape provides a variety of foods including seeds, fruits, flowers, nuts, bulbs and corms including the corms of the introduced Onion Grass.
- The increase in local cockatoo populations is attributed to changes in farming practices. Ploughed ground attracts the birds, which feed on exposed bulbs and later on germinating cereal (wheat, oats, barley) seeds. Cereal crops may be used as a food source and the stubbles left once the crops are harvested or slashed paddocks, also attract large flocks of cockatoos seeking remnant grain or seeds.
- Cockatoos are highly intelligent birds and it is likely that one of their motivations for roosting in towns is that they feel safer.
Cockatoo behaviour
Seasonal activity
- Cockatoos’ seasonal activity patterns are influenced by food availability and breeding activities. The birds nest in hollows in large old trees in spring and often will use the same hollow year after year. When pairs are breeding, birds are dispersed over the countryside, where they feed near their nest hollows. After the young fledge (early November), they join growing flocks that gather to feed from concentrated food sources. As the ground hardens, cockatoos rely more on surface seeds and less on digging for bulbs and corms.
- It is often not until the autumn rains soften the ground allowing for the digging of bulbs and corms that the large flocks once again disperse into smaller groups for the winter. By August, pairs have once again moved close to their nest hollows to feed and prepare for breeding.
Typical daily activity
- The birds leave their roosting site in the morning to forage, and then usually return to a resting or “loafing” site to digest food, preen, play and rest.
- Once the day is cool enough, the birds resume feeding late in the afternoon. The resting or loafing site is often close to the current food source but is not usually the roosting site.
- The birds then return to the evening roost site near sunset and are often noisy while settling to roost. On moonlit nights, the cockatoos often call and move about the roost site.
- Wherever cockatoos land, either feeding or beak maintenance occurs to keep their constantly growing beaks at the correct length and condition.
Cockatoos’ legal status
- Cockatoos are native wildlife and are protected under the Wildlife Act 1975. It is illegal to wilfully disturb or to destroy protected wildlife without approval. Note: Cockatoos have been declared “unprotected wildlife” in certain situations allowing anyone specified in the Governor in Council Order to shoot these birds but it must only occur on the property where the damage is occurring.
- The most common approval to scare, disperse or destroy protected wildlife is an Authority to Control Wildlife (ATCW). Landholders who are experiencing damage and wishing to scare, disperse or destroy cockatoos must apply to DELWP for an ATCW.
- It is DELWP policy that an ATCW applicant must try non-lethal control options if available, before being able to apply for an ATCW for lethal control. Where an ATCW for lethal control using a firearm is applied for in residential areas, public open spaces and thoroughfares, the applicant will also require a populous place permit, which is issued by the Victoria Police.
Cockatoo Management methods
Non-lethal control options suggested: (requires an ATCW from DELWP and maybe a
Populous Place Permit)
- Scaring measures must be constantly varied and may need to be sustained for several weeks
- Options include big-eye balloons, kites resembling birds of prey, flashlights, recorded alarm calls, scare guns, and deployment of Bird Frite cartridges (pyrotechnic ‘crackers’ fired from a 12-gauge shotgun).
- Note: The use of recorded alarm calls, scare guns and the Bird Frite cartridges are not considered suitable for use within the township. EPA Noise Control Guidelines apply.
Lethal control options
Shooting:
- Shooting is a common technique and may result in a short-term behaviour change however it is unlikely to have much impact on the overall population size or its ability to recover to former numbers.
- Unless shooting is carried out over a large area, new birds will quickly move in to replace those that have been shot or scared away.
- Shooting may increase the extent of damage if birds are constantly moved around.
Illegal methods of control include:
- Trap and gas
- Poisoning
- Birds of Prey
Ian Temby has noted that even the visual deterrent techniques mentioned above are unlikely to have any long-lasting effects as the corellas within townships are already accustomed to the sights and sounds of an urban area.
Leanne Rolfe
Surf Coast Shire Environment Officer – Biodiversity