How Did We Get Off the Goo?


Many people have been curious about the way we at International Bird Rescue were able to clean the birds affected by the San Francisco Bay Mystery Goo Spill in January 2015 (Fig 1).


washing bird IBR

Figure 1. Surf scoter (Melanitta perspicillata) treated with baking soda paste during removal of the mystery goo. Photo credit: International Bird Rescue.


Before the wash

When faced with an unknown contaminant that needs to be removed from an animal, we first try what is known to work well for other contaminants on a few plucked feathers. A typical and effective wash for petroleum contamination involves Dawn® dish soap (Procter and Gamble) with or without pre-treatment with a non-toxic solvent called methyl soyate, made from soybeans. Pre-treatment agents help break up dry or weathered asphalt-like material. Unfortunately Dawn plus methyl soyate did not do the job in the case of “goo” birds.

When our typical wash procedure does not do the trick, we have to get creative, however a wash procedure must show good odds of success before we will subject a live bird to the stress of washing. We are also limited in what solvents can be used because many agents are too toxic for use on live animals, such as non-polar solvents like hexane. Hence, we generally only use products that are safe for human use.

We initially thought the “mystery goo” might be a silicone-based product, which we know from experience is very hard to remove. Our “bird-washing wizards” (i.e. IBR senior rehabilitation staff) tried a variety of products like baby oil, vinegar, and other options on “gooed” feathers from birds that did not arrive alive. A variety of procedures and application of products in different orders, using different methods for varying lengths of time were tried.

After much experimentation, we decided to try the most effective procedure on a few live birds, and then see if the birds were able to become waterproof afterwards. We wanted to know how the first group did before inflicting the long procedure on more birds. Thankfully, despite taking about twice as long as a wash for an oiled bird, this technique worked acceptably well and we were able to proceed with cleaning all the birds. Below is the procedure we used (Table 1).

CAVEAT: As in all animal care, the condition of the animal is of supreme importance. First and foremost any bird being cleaned must be medically stable before any attempts at cleaning, lest the stress of the washing kill the bird. Extreme care must be taken to prevent the bird from becoming chilled or overheated during washing, rinsing, or drying. All cleaning products must be thoroughly rinsed off at the end of the wash, as these products also contaminate the plumage.

Cleaning “mystery goo” birds

This goo removal technique first involved application of “pre-treatment” agents worked into the feathers, then birds were washed and finally rinsed until water began to bead up and roll off the plumage (Fig 2-Fig 4). While resting in a clean cage, birds are dried, while being carefully monitored for evidence of overheating (Table 1).

Table 1. Procedure used by International Bird Rescue to remove the “Mystery Goo”
  1. Soak affected body areas in methyl soyate
  2. Apply baking soda + water paste, working it into the feathers
  3. Apply white vinegar and work it into the feathers while it foams
  4. Wash the bird with concentrated Dawn® dish soap
  5. Thoroughly rinse the bird
  6. Dry the bird


assembly line IBR

Figure 2. When housed out of water, seabirds are kept in soft sided, net-bottom pens to prevent captivity-related lesion formation. These are standard housing for non-waterproof seabirds during oil spills. Photo credit: International Bird Rescue.


fine feathers toothbrush

Figure 3. Methyl soyate being applied to a horned grebe (Podiceps auritus), and worked into the feathers with a soft toothbrush. Photo credit: International Bird Rescue.


rinsing bird IBR

Figure 4. All cleaning products must be thoroughly rinsed off before the bird will be able to become waterproof again. Photo credit: International Bird Rescue.



After the “mystery goo” was removed, the birds entered the waterproofing process, a completely separate and complex process in which birds are managed so they can begin to preen and realign feathers.


Further reading

Massey JG. Summary of an oiled bird response. J Exotic Pet Med 15(1):33-39, 2006.

Miller E, Bryndza H, Milionis C, et al. An evaluation of the efficacy of eighty-six products in the removal of petrochemicals from feathers. Proc Sixth International Effects of Oil on Wildlife Conference 2000: 55-66.

Munaweera K, Ngeh LN, Bigger SW, Orbell JD. Towards a rational choice for pre-treatment agents for the cleansing of oiled wildlife. Proc Annu Conf Australian Wildlife Rehabilitation Conference. 2012. Available at Accessed Sep 12, 20015.

Ratliff C, Gentry J, Schmalz S, Heatley JJ. Veterinary response to animal contamination. J Exotic Pet Med. Published electronically Aug 21, 2015.

U.S. Fish and Wildlife Service. Best Practices for Migratory Bird Care During Oil Spill Response. November 2003. Available at Accessed September 8, 2015.

Ziccardi M. Oil spill: Oil effects on wildlife & general medical concerns. Proc Annu Conf American Board Vet Practitioners 2011. Available at Accessed on Sep 7, 2015.

To cite this page:

Duerr R. How did we get off the goo? March 17, 2016. LafeberVet Web site. Available at