After the Exxon Valdez oil spill, ALL oiled animals were counted and documented by qualified observers. The final official tally for oiled birds was between 100,000 and 250,000 oiled seabirds and at least 247 oiled Bald Eagles.
Everything changed with the BP spill. Official counts now include ONLY animals that are physically retrieved, and to minimize the numbers even further, the rules for picking up oiled animals have become horribly restrictive, limiting who is allowed to pick up animals (prohibiting most licensed rehabbers experienced with retrieving oiled animals) and prohibiting capture of many severely oiled animals for specious reasons. The final tally of 7,000 oiled birds after the BP spill was a woefully inaccurate undercount.