Small (<10%) = 10
Medium (10%-50%) = 5
Large (>50%) = 0
ii) Distribution trend (DT): Estimated from documented extirpations. An additional five points was added if extirpations have been documented since 1994 when taxa were last evaluated for SSC status.
Severely (>80%) reduced = 20
Moderately (>40-80%) reduced = 15
Slightly (<20%) reduced or reductions suspected = 5
Stable (~0% reduced) or increasing = 0
Extirpations since 1994 = +5
iii) Population concentration/Migration (PC): Determined from natural history and ecological information. This metric assesses vulnerability during a particular life stage when populations are concentrated in small areas relative to their total range, such as in pond breeding amphibians.
Vulnerable life stages = 10
No vulnerable life stages = 0
iv) Percent of entire range in California (PE): Estimated from range maps.
100% (endemic) = 10
>66-99% = 7
>33-66% =3
<33% = 0
v) Ecological tolerance (ET): Evaluated based on available natural history and ecological information.
Narrow ecological specialist on rare resource = 10
Narrow ecological specialist on common resource = 7
Moderate ecological specialist = 3
Broad ecological tolerance = 0
vi) Population trend (PT): Estimated from documented declines in population abundance at currently occupied localities. An additional five points was added if declines have been documented since 1994 when taxa were last evaluated for SSC status.
Severe declines (>80% reduced) = 20
Great declines (40-80% reduced) = 15
Moderate declines (20-40%) = 10
Slight or suspected declines, trend unknown = 5
Stable (~0 % reduced) or increasing = 0
Declines since 1994 = +5
vii) Vulnerability to climate change (VC): The VC metric score is a combination of the climate change threats within the taxon’s geographic range and the taxon’s sensitivity to those threats. The following potential climate changes were considered: wildfire, snowpack, temperature, precipitation, vegetation. Predictions for the directions of changes for each factor in each bioregion of California were determined from Climate Action Team Reports and a special issue of the journal Climatic Change (California at a Crossroads: Climate Change Science Informing Policy Volume 87, Supplement 1, March, 2008). Sensitivity to these predicted changes was estimated from known natural history and ecological information for each taxon. To be conservative, we assessed sensitivity under the assumptions that animals would not migrate or adapt in response to climate change.
Highly sensitive = 10
Moderately sensitive = 7
Slightly sensitive = 3
Unlikely to be sensitive = 0
viii) Projected Impact of Threats Over the Next 20 Years (PI): Estimated from potential impacts of known threats such as planned development and stochastic events like disease outbreak.
Seriously reduce (>20%) = 10
Moderately reduce (>10-20%) = 7
Slightly reduce (>5-10%) = 3
No substantial net impact (<= 5% or increase) = 0
