Sea otters are subject to both external and internal petroleum hydrocarbon exposure during an oil spill. External oiling is the most obvious condition, and usually the first point of contamination. Internal exposure to oil can occur via several routes including dermal absorption, inhalation of hydrocarbon vapors, and ingestion by eating contaminated prey or licking oiled fur. All three routes can contribute to systemic petroleum hydrocarbon toxicity. Sea otter grooming behavior exacerbates the situation and increases the degree of oil exposure. In an effort to clean their fur, they often spread the area of contamination and may actively inhale or ingest oil (Mulcahy and Ballachey, 1993; T. M. Williams, personal observation).
This chapter focuses on the immediate actions required when oiled animals arrive at rehabilitation centers. We describe the methods for stabilizing oiled otters, determining the degree of oil contamination, conducting clinical evaluations, and initiating treatments. A method for assessing petroleum hydrocarbon toxicity using paraffinic hydrocarbon concentration in the blood is presented. We also describe the major medical problems of oiled sea otters. The incidence and initial treatment of these conditions are discussed with respect to the type and age of the spill. Subsequent treatment regimens and methods for cleaning the animals are addressed in Chapter 5 and Chapter 6, respectively.
