Frequently Asked Questions
Effects of Oil on Wildlife
Q: What are the primary effects of oil on birds?
A: The primary problem involves physical alteration of the feather structure. When oiled, feathers lose their ability to trap air and repel water. As a result, birds can no longer maintain body heat; they become hypothermic; and their need for food increases. At the same time, due to oil on their plumage, birds do not float well; their swimming and foraging ability decreases; and they often cannot fly and will haul out of the water.
Q: What are the primary effects of oil on marine mammals?
A: There are different effects on different classes of marine mammals. Heavily furred animals, such as sea otters and fur seals, are more severely affected by oiling because these species rely on their thick haircoat to maintain warmth and buoyancy. The fur traps a thin layer of air adjacent to the animal’s skin (in a similar fashion to birds), and this air layer prevents the skin of the animal from coming into contact with the cold ocean water. When exposed to oil, the alignment of the hair is altered; the air layer is destroyed; and mammals rapidly become hypothermic. For marine mammals without heavy haircoats (such as other species of seals, sea lions, dolphins and whales), problems associated with hypothermia are less of a concern because their thick blubber protects them from the cold, with the exception of juveniles that have not yet developed this protective layer. However, problems associated with fume inhalation, dermal exposure, and ingestion are still concerns for these species, as they are in birds and fur-bearing marine mammals.
Q: Can the ingestion of oil by wildlife be toxic?
A: Yes. External oiling almost always leads to some oil ingestion. Birds, fur seals, and sea otters preen or groom themselves meticulously to maintain a feather or hair alignment that creates the insulating air layer. Marine mammal pups can ingest some oil while nursing. Depending on oil intake, this internal exposure has been shown to cause disruption in normal internal organ function in birds and otters, as well as effects on the reproductive and immune systems.
Q: What are the long-term effects associated with oil exposure after care in a response center?
A: Long-term effects are difficult to assess because limited research has been done thus far following spills using OWCN protocols. This lack of information, however, is actively being addressed by the OWCN through the funding of selected post-release research studies. One such study on western gulls suggested that birds survived for long periods of time following oil exposure and rehabilitation. A common murre study that is currently underway suggests much better survival than previously reported. Other studies conducted following rehabilitation (using non-OWCN protocols) have found variable survival rates and behavioral effects of oiling and rehabilitation in pelicans, coots, murres, and penguins.
Q: What are the effects of oil on wildlife reproduction?
A: Studies on the effects of a single drop of oil on eggs from different species of birds have shown significant mortality and developmental defects in affected embryos. Studies on mink (the research model for sea otters) exposed to petroleum products have shown decreased whelping rates and pup survival.
Q: Do different types of oil have different effects on wildlife?
A: Yes. The lighter, more volatile petroleum products (such as kerosene and jet fuel) can cause significant burns, eye irritation, neurological signs, and lung damage from inhalation of fumes. The heavier products (such as crude oil) most obviously affect waterproofing, but also cause other physiological problems when ingested or absorbed through the skin. It should also be remembered that even non-toxic oils, such as vegetable oil and fish oil, can be extremely damaging to wildlife because they affect the plumage of birds and hair of fur-bearing mammals and cause a loss of waterproofing similar to petroleum oils.
Q: How long does it take to rehabilitate a bird?
A: On average, rehabilitation requires 1-3 weeks. The time in captivity depends on a number of factors, including the number of animals affected, the terrain to be searched, weather, and characteristics of the spill (i.e., type of petroleum product, manner of spillage, success of containment, etc.).
Q: What factors might influence the survival of oiled wildlife cared for in response centers?
A: Many different factors affect the ultimate survival and release of oiled wildlife. These include the proximity of an appropriately equipped response facility to the spill site, water and air temperature, species and age of affected animals, toxicity of the petroleum product, how rapidly animals are captured from the environment and availability of trained personnel.
Steps in an Oil Spill Response
Q: What are the steps involved in an OWCN response?
A: 1) Activation of the OWCN; 2) Search and collection; 3) Intake and stabilization; 4) Cleaning; 5) Recovery and pre-release assessment; and 6) Release. A more detailed explanation of these steps can be found on the Response page.
OWCN Organization
Q: How many OWCN facilities are there in the state?
A: Currently there are 23 participating Network organizations throughout California. These include facilities constructed specifically for oiled wildlife response (including facilities in Arcata, the San Francisco Bay Area, Santa Cruz, Los Angeles, Huntington Beach, and San Diego), facilities that have been renovated or improved in order to allow for oiled wildlife care, and existing organizations who have been provided supplies, equipment and training in order to assist in the response in oil spill emergencies. During non-oil spill periods, facilities built or improved by the OWCN are used for general wildlife rehabilitation research; primary, secondary and professional education; and other activities by the participating organizations.
Q: How is the OWCN supported?
A: The OWCN is a joint program between the California Department of Fish and Game Office of Spill Prevention and Response and the UC Davis School of Veterinary Medicine Wildlife Health Center. It is financially supported by interest earned on the state of California’s Oil Spill Response Trust Fund funded by fees assessed to the oil transportation industry.
Q: How many trained personnel participate in the OWCN?
A: The OWCN maintains a trained cadre of over 200 people affiliated with our participating organizations through an annual training program. We employ a relatively small core of veterinarians and administrative personnel to manage the Network and to supervise activities during oil spill events. The Network also contracts with the International Bird Rescue Research Center to be the primary rehabilitation organization during events involving birds. The OWCN works closely with the California Department of Fish and Game, the U.S. Fish and Wildlife Service and the National Marine Fisheries Service during spills. Ultimately, the Network relies on a large number of trained volunteers (who are associated with participating organizations) to assist during spill events. These volunteers are trained by the OWCN in basic animal handling, care and rehabilitation techniques, as well as OSHA-certified HAZCOM/HAZWOPER practices and Incident Command System procedures.