Lead Utility Index

A. EXPOSURE POTENTIAL
1. Primary foraging technique
10—Dives under water, feeds off bottom
8—Dabbles under water, feeds off bottom
7—Ground gleaner
5—Probes below surface, long bill length (>5 cm)
4—Probes below surface, short bill length (<5 cm)
1—Does not feed in any of these manners

2. Dietary preference
5—Predator or scavenger of (waterfowl)
3—Predator or scavenger of other game species
1—Does not feed in this manner

3. Use of hunted areas
5—Readily inhabits or forages in hunted areas
3—Occasionally inhabits or forages in hunted areas
1—Does not generally utilize hunted areas

4. Longevity
5—Long-lived (>15 years)
3—5-15 years
1—Short-lived (<5 years)

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

2. 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)


C. EASE OF COLLECTION
1. Population concentration
5—Highly colonial or gregarious
3—Semi-colonial or semi-gregarious
1—Solitary

2. Accessibility of sampling unit
5—Individuals or nests are easily accessible
3—Individuals or nests are moderately accessible
1—Individuals or nests are difficult to access

3. Ease of capture or trappability
5—Easy to capture or trap
3—Moderate
1—Difficult

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

5. Federal or state management status in study area
5— Not protected or managed
4—Protected (managed population)
3—Threatened
1—Endangered

D. QUANTITY OF EXISTING EXPOSURE AND
EFFECTS DATA
5—Substantial data
3—Some data
1—Very little data