Gray wolves ( Canis lupus ) in upper Michigan have been monitored since 1991 when breeding activity in mainland Michigan, USA, was documented for the first time since 1954 . Based on winter track counts, the mean annual rate of increase in abundance was 19% from 1995 to 2002 , with the population reaching an estimated 278 animals in 2002 . Our objectives were to ( 1 ) increase the efficiency of wolf management in Michigan by evaluating alternative and less extensive sampling approaches for population estimation, and ( 2 ) evaluate habitat for wolves based on occupancy after a decade of recovery. For the first analysis, we created 22 discrete sampling units that cover upper Michigan, and we evaluated abundance estimates based on various sampling plans using known dis- tribution and populations from the 2000 – 2002 winter track surveys. We evaluated each plan based on the precision, bias, and confidence interval coverage. A random sampling plan with regression estimator returned the most pre- cise estimates, but a stratified sampling plan, using low, medium, and high wolf density strata had the greatest pre- cision at lowest effort. For the habitat evaluation, we compared white-tailed ( Odocoileus virginianus ) deer density and road density between wolf pack locations from 1995 to 2001 to random locations outside of the current wolf range. We estimated white-tailed deer density by a spatial interpolation of pellet group counts. Our resource selec- tion function indicated that probability of wolf occupation of an area was positively correlated with deer density, and it was relatively constant for road densities <0 . 4 km/km 2 but declined sharply at higher road densities. For areas habitable by wolves in upper Michigan, we predict a road density threshold of 0 . 7 km/km 2 and a deer den- sity threshold of approximately 2 . 3 – 5 . 8 deer/km 2 . We believe that these results will aid managers who need to esti- mate wolf abundance and predict wolf distribution.
Herrera Carranza, J. (2002). Objetivos de la atención farmacéutica. Atención Primaria, 30(3), 183–187. https://doi.org/10.1016/s0212-6567(02)79001-x