Petroleum Crude Oil Vulnerability Index

A. EXPOSURE POTENTIAL
1. Time spent on or in water
5—Nearly always
4—Most of the time
3—Half of the time
2—Less than half of time
1—Seldom or never

2. Escape behavior
5—Dives
4—Swims, but sometimes dives
3—Swims
2—Flies, but sometimes swims
1—Flies

3. Primary foraging technique
5—Dives or is submersed in water
4—Dabbles in water
3—Probes mud
2—Skims surface of water
1—Does not forage in water

4. Preening or grooming behavior
5—Preens or grooms feathers or fur
1—Does not preen or groom

5. Exposure of eggs
5—Eggs laid in water
4—Eggs laid near water
3—Eggs laid away from water, transfer from adult likely
(e.g., waterbirds)
2—Eggs laid away from water, transfer from adult not
likely (e.g., turtles, terrestrial birds)
1—Does not lay eggs or does not breed in study area

6. Use of urbanized areas or shipping channels
5—Readily inhabits and/or forages in these areas
3—Occasionally utilizes these areas
1—Avoids these areas

7. Residency
5—Year-round resident (does not migrate)
4—Migrates within study area
3—Migrates beyond study area (present during breeding)
2—Migrates beyond study area (present during winter)
1—Transient (present during migration only)

8. Social structure
5—Highly colonial or gregarious
3—Semi-colonial or semi-gregarious
1—Solitary

9. Range
5—Present in small part of study area only
4—Present throughout less than half of study area
3—Present throughout about half of study area
2—Present throughout more than half of study area
1—Present throughout entire study area

B. SENSITIVITY
1. Effect of oil on waterproofing/insulation
5—Difficult to regain waterproofing/ insulation
(cormorants, diving ducks, most mammals)
3—Able to regain waterproofing
(shore birds, upland birds, other ducks)
1—Waterproofing/insulation not greatly affected
(reptiles, amphibians, seals, seas lions, cetaceans)

2. Feeding specialization
5—Highly specialized
4—Somewhat specialized
3—Moderately adaptable
2—Very adaptable
1—Generalist

3. Ability to metabolize and clear hydrocarbons
5—Low (fish-eating birds)
3—Moderate (other birds and mammals, reptiles)
1—High (rodents and lagomorphs, gallinaceous birds)

C. RESILIENCE OF POPULATION
1. Abundance in study area
5—Rare (Not normally present)
4—Occasional (Presence possible, but not expected)
3—Uncommon (Presence expected, but not a certainty)
2—Common (Certain to be in suitable habitat)
1—Abundant (Numerous in suitable habitat)

2. Distribution outside of study area
5—Endemic to study area
3—Present outside of study area, but not abundant
1—Abundant outside of study area

3. Reproductive potential
5—Low (1-2 offspring per year)
3—Moderate (3-4 offspring per year)
1—High (>4 offspring per year)

4. Age at first breeding
5—6+ years
4—5 years
3—4 years
2—3 years
1—1-2 years