Efficacy of seawater for washing oiled birds during an oil spill response

Highlights: • Aquatic oil pollution events are detrimental to wildlife, particularly birds. • To decontaminate birds, large quantities of freshwater are required. • Here we investigated seawater use for cleaning live birds, mallard ducks. • Results indicate the use of seawater for decontamination wash/rinse was effective. • Seawater wash has global application, particularly in areas with limited freshwater. - Abstract: Aquatic pollution events can be detrimental to the survival of wildlife, particularly birds. To decontaminate affected birds, large quantities of fresh water are required. A recent study using seabird feathers, demonstrated that seawater wash/rinse can effectively remove oil from feathers. However to determine whether seawater was effective for live birds, we used 36 mallard ducks to replicate the oiled feather wash/rinse study. We investigated the time and volume of water used, bird water-proofing scores after daily swims and a barbule amalgamation index (BAI), for feathers collected at stages throughout the process. Results indicate that for oiled mallard ducks, the use of seawater for decontamination wash/rinse was effective. Seawater wash however, took longer and used a greater quantity of water. Time to birds being waterproof, was not significantly different between groups. The use of seawater has worldwide application for oiled wildlife response activities particularly in areas where freshwater supplies are limited.