21 January Update: Birds are now being found on western side of San Francisco Bay as numbers continue to climb. The latest reports include more than 300 birds found and more than 80 dead. No further information on the nature of the substance is available yet.
More than 240 birds, covered in a viscous substance that is not petroleum-based, have been rescued in the San Francisco Bay area since Friday, 16 January 2015. As of 19 January, 25 birds were reported dead, 55 have been washed and the rest are being stabilised before washing.
Test results are still pending but the substance is reported to be similar to polyisobutylene (PIB), a substance that affected more than 4,000 birds in the UK and Belgium during two incidents in 2013. Species rescued in the US so far include surf scoters, buffleheads, horned grebes and common goldeneyes.
The birds are being cared for at the Northern California International Bird Rescue facility, where a modified wash protocol using a pre-treatment solution, baking soda, and vinegar in addition to the normal routine, appears to be successful in removing the sticky coating.
Three search and rescue teams continue to patrol beaches in Alameda, San Leandro and Hayward, on the east side of the bay where the initial birds were found. The California Department of Fish and Wildlife’s law enforcement staff is investigating the incident and its Wildlife Investigation Laboratory is performing necropsies to determine the cause of death.
PIBs are used chewing gum, adhesives and sealants. Discharges of PIBs within 12 miles of a coastline are illegal under Marpol (The International Convention for the Prevention of Pollution from Ships). Beyond the 12-mile limit, discharges are subject to certain conditions but efforts by both wildlife NGOs and the shipping industry to make any discharge of PIBs illegal are ongoing.
Resources:
Sticky substance kills two dozen seabirds. SFBay.ca. Accessed online 19.Jan.2015
Update:Mystery substance toll on bay area seabirds rises sharply. International Bird Rescue Blog. Accessed online 20.Jan.2019