International Bird Rescue, the organization that brought in so many of the birds, said on Tuesday that it's spent $150,000 cleaning them up.
While 300 of the birds have died, some 78 are still being treated.
And because the goo didn't come from a spill or leak, International Bird Rescue has had to cover the entire cost.
Click here if you would like to make a donation.
PHOTOS: Clean seabirds released back into wild after being covered in mystery goo