Environment

Avian (bird) botulism is a disease that causes progressive weakness, paralysis and eventually death in water birds.

Water birds eat plants and invertebrates, such as maggots, insects and worms, and in the process ingest the botulism toxin released by the bacteria Clostridium botulinum, a bacterial species that is naturally present within wetlands and lakes round the world. During warmer periods of the year, when water and soil temperatures are also warmer, bacterial numbers increase. Feeding water birds bread can also increase the risk of them being affected by botulism.

Feeding water birds can unintentionally cause them harm and pollutes their habitats. They eat a diet of insects, snails and worms and should not be fed bread or other foods, which can cause malnourishment, sickness and dependence on the wrong diet. Bread also raises nutrient levels in the water, which leads to an increase in soil bacteria that causes avian botulism.

Contact Western Australian Seabird Rescue (08) 6102 8464. Residents are reminded that WA Seabird Rescue is a volunteer organisation. Or contact the City as soon as possible on 9405 5000 to report it.

Removing healthy birds from the lake system is not an effective or practical approach to preventing the spread of avian botulism. Most birds will find their way back to the lake system and the stress of being removed from their habitat can make them more susceptible to disease.

Avian botulism or the Type C identified at Kingsbridge is not known to be harmful to humans. Kingsbridge lake system is an ornamental lake and swimming in the water is not permitted.

The City recommends that dogs be kept on leads near Kingsbridge Lake to prevent them going in the water. It is rare for dogs to contract botulism but it is possible, so caution is recommended. Most cases of botulism in dogs are caused by eating dead animals or contaminated raw meat.

Draining the lake is not a recommended action to prevent botulism. Draining the water will raise its temperature and increases the likelihood of botulism toxin occurring because it can be present in the silt and organic matter on the base of the lake.

An urban water management specialist has also been engaged by the City to assess the lake system and provide recommendations to ensure water quality. The City will remove organic matter from the lake’s edge and clear any rubbish or items that obstruct water flow between the lakes.

Keeping our waterways and their surrounds free of rubbish is an important way to protect our wildlife and precious environment. When visiting parks or reserves in the City, please put your rubbish in the bin, or take it home with you. Dispose of waste sensibly so it doesn’t end up in our waterways. Together we can ensure our recreational areas are kept in pristine condition, and please remember not to feed water birds. It can make them sick and dependent on humans.