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Table 1 Environmental variables used to measure hypothesized environmental drivers of body size patterns in grizzly bears within Alberta, Canada

From: Environmental, biological and anthropogenic effects on grizzly bear body size: temporal and spatial considerations

Hypothesized environmental driver and measurement variable Units Measurement location(s)§ Temporal scale(s)
A. Regional habitat productivity    
  Temperature (Winter, Spring, Summer) °C home range 1971-2000
  Precipitation (Winter, Spring, Summer) mm home range 1971-2000
  Ecosystem categories telemetry C t-1
B. Inter-annual environments (deviations)    
  Temperature (Winter, Spring, Summer) °C home range Bt-1, t 0, t+1 & Ct-1, t 0
  Precipitation (Winter, Spring, Summer) mm home range Bt-1, t 0, t+1 & Ct-1, t 0
C. Local habitat quality    
  Shrub habitat (quadratic) % telemetry C t-1
  Canopy cover (quadratic) % telemetry C t-1
  Variation in canopy cover % telemetry C t-1
  Deciduous canopy cover (quadratic) % telemetry C t-1
  Forest age (quadratic) years telemetry C t-1
  Forest age variation years telemetry C t-1
  Regenerating forest habitat (quadratic) % telemetry C t-1
  Variation in regen. forest age years telemetry C t-1
  Soil wetness (quadratic) index telemetry C t-1
D. Human footprint & activity    
  Private lands % telemetry C t-1
  Protected area % telemetry C t-1
  Mortality risk index telemetry C t-1
  Safe harbour habitat index telemetry C t-1
  Linear feature density km/km2 telemetry C t-1
  Distance to human feature m telemetry C t-1
  Distance to active energy well m telemetry C t-1
E. Landscape change    
  Annual rate of habitat change % telemetry C t-1
  1. § Home ranges estimated by 50% multi-annual kernels; climate variables measured at kernel centroid; † Temporal scales relate to time of measurements; B relates to birth year & C to capture year. For inter-annual variation, 2-yrs prior to and up to 1-yr following birth or 1-yr prior to and the year of capture are considered.