Over the past 30 years, Phillip Island Nature Parks has developed protocols on how to treat oil affected little penguins. Currently, these protocols have resulted in 96% of oiled penguins received at the Phillip Island Nature Parks’ Wildlife Clinic being released back into the wild.

The use of jumpers on oiled penguins was first trialled in 1998, and since then the knitting pattern has been refined. This pattern ensures that the wool does not damage penguin feathers and that flippers or beaks do not get caught. Jumpers are placed, temporarily, on oiled little penguins after they are collected and prior to washing, primarily to reduce the amount of oil that penguins ingest. Once feathers become matted with oil, the birds try preening themselves clean, often ingesting toxic oil that may affect their recovery or survival.

Following the Iron Baron spill in 1995 in northern Tasmania (before jumpers were commonly used), rehabilitated oiled birds had a reduced number and quality of chicks in the two breeding seasons after oiling. This may be due to physiological damage incurred by ingesting oil prior to being cleaned.

Feather matting with oil also interferes with penguins’ thermoregulation by allowing water and cold air to come in contact with the skin. Jumpers used in penguin rehabilitation are ideally 100% wool to keep the penguins warm, whilst still being breathable. However, jumpers knitted with acrylic wool can still be used in these oil pollution emergency situations. Additionally, the birds are also kept in temperature-controlled rooms to further reduce the chances of hyper- or hypothermia. The wool also aids in absorbing some of the oil from the feathers. Penguin jumpers are not reused so as to avoid the spread of oil between birds and the potential transfer of pathogens from one bird to another.