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Range DescriptionStrix occidentalis has a population of c.15,000 individuals in four subspecies: caurina has a minimum of 3,778 pairs and 1,001 territorial individuals from south-west British Columbia, Canada, to north California, USA; the nominate has a minimum of 3,050 individuals in central and south California, USA, and (formerly) Baja California, Mexico; lucida has a minimum of 777-1,554 individuals from Utah and Colorado to Arizona, New Mexico and extreme west Texas, USA, and also occurs in Sonora, Chihuahua and Nuevo Len to Jalisco, Durango, Michoacn and Guanajuanto, Mexico (Johnsgard 1988a, Sibley and Monroe 1990, Gutirrez et al 1995, Lammertink et al. 1996, AOU 1998); and juanaphillipsae has been recently described from the State of Mxico (Dickerman 1997). Mexican populations may be stable because forestry activities there typically modify rather than destroy habitat (Lammertink et al. 1996, J. M. Lammertink in litt. 1998). Most other populations are declining and, in some, the decline is accelerating because of clear-felling and selective logging (Gutirrez et al 1995, Noon and McKelvey 1996). Subspecies caurina is estimated to be in significant decline, at 3% per year range-wide and 7% per year in Washington State (S. Holmer in litt. 2011), and is close to extinction in Canada. The most recent information on the numbers of subspecies lucida in Arizona indicates that the population there is stable, but the population in New Mexico is estimated to be declining at a rate of 6% per year (B. Bird in litt. 2011). Overall, the population is suspected to be in decline, although the rate of decline has not been estimated.