Black-billed Magpie (Pica hudsonia) Conservation Status Review
Review Date = 12/22/2011
Population Size
ScoreU - Unknown
CommentUnknown.
Range Extent
ScoreG - 200,000-2,500,000 km squared (about 80,000-1,000,000 square miles)
Comment380,531 square kilometers based on Natural Heritage Program range maps that appear on the Montana Field Guide
Area of Occupancy
ScoreU - Unknown
CommentUnknown.
Long-term Trend
ScoreE - Relatively Stable (±25% change)
CommentPopulations prior to European arrival and extirpation of bison were almost certainly higher than their current level, but are probably stable in terms of being within +/-25% of pre-European numbers.
Short-term Trend
ScoreE - Stable. Population, range, area occupied, and/or number or condition of occurrences unchanged or remaining within ±10% fluctuation
CommentBBS data for Montana is of highest credibility and shows a nonsignificant -0.8% decrease per year or 8% decrease per decade. Mostly stable to minor declines on prairies for surrounding states and provinces, but some minor increases in more mountainous areas of Wyoming and Idaho.
Threats
ScoreG - Slightly threatened. Threats, while recognizable, are of low severity, or affecting only a small portion of the population or area.
CommentDisease and human persecution are probably the greatest threat to the species, but these are likely minor threats in Montana.
SeverityLow - Low but nontrivial reduction of species population or reversible degradation or reduction of habitat in area affected, with recovery expected in 10-50 years.
CommentWest Nile Virus does not seem to have major impacts on populations and persecution is probably minor.
ScopeLow - 5-20% of total population or area affected
CommentProbably less than 20% of the population is being threatened by disease or human persecution during any given year.
ImmediacyModerate - Threat is likely to be operational within 2-5 years.
CommentOngoing
Intrinsic Vulnerability
ScoreC - Not Intrinsically Vulnerable. Species matures quickly, reproduces frequently, and/or has high fecundity such that populations recover quickly (< 5 years or 2 generations) from decreases in abundance; or species has high dispersal capability such that extirpated populations soon become reestablished through natural recolonization (unaided by humans).
CommentNot Intrinsically Vulnerable. Species matures quickly, reproduces frequently, and/or has a high fecundity such that populations recover quickly (< 5 years or 2 generations) from decreases in abundance. Species has good dispersal capabilities such that extirpated populations generally become reestablished through natural recolonization.
Environmental Specificity
ScoreC - Moderate. Generalist. Broad-scale or diverse (general) habitat(s) or other abiotic and/or biotic factors are used or required by the species but some key requirements are scarce in the generalized range of the species within the area of interest.
CommentModerate Generalist. Species uses a variety of open to semi-open habitats with suitable nesting habitat.
Raw Conservation Status Score
Score
3.5 + 0.0 (geographic distribution) + 0.0 (environmental specificity) + 0.0 (short-term trend) + 0.75 (threats)