CHANGES IN THE WINTER DISTRIBUTION OF THE ROUGH-LEGGED HAWK 
Period 
Figure 3. Average numbers of the Rough-legged Hawk (RLHA) and Red-tailed Hawk 
(RTHA) per 100 party hours in four successive 7-year periods (1, count years 79-85; 
2, count years 86-92; 3, count years 93-99; 4, count years 100-106) for the North 
and South Pacific Coast regions. 
there. Within both Pacific Coast regions the human population of counties 
associated with the CBC circles increased substantially (26% for the North 
Pacific Coast; 59% for the South Pacific Coast). 
Intermountain West Regions 
The North Intermountain West had the highest Rough-legged Hawk 
abundance of any region and the second-highest Red-tailed Hawk abundance 
1 2 3 4 1 2 3 4 
Period 
Figure 4. Average numbers of the Rough-legged Hawk (RLHA) and Red-tailed 
Hawk (RTHA) per 100 party hours and number of December days with snow cover 
in excess of 5 cm in four successive 7-year periods (1, count years 79-85; 2, count 
years 86-92; 3, count years 93-99; 4, count years 100-106) for the North and 
South Inter mountain West regions. 
216 
