Table A.1 Summary statistics for June/July aerial Dall’s sheep surveys in interior Alaska Military Operations Areas.
| Total Counts |
Per 100 Ewes |
Rams |
||||||||||||||
| Survey Unit |
Year |
Total Sheep |
Survey Time |
Ewes |
Lambs |
Yearlings |
Rams |
Lambs |
Yearlings |
Rams |
Legal Rams |
Sublegal* |
% Legal |
|||
| Diamond Fork |
1983 |
7 |
0 |
0 |
0 |
7 |
2 |
5 |
29 |
|||||||
| 1990 |
19 |
1.70 |
2 |
2 |
0 |
15 |
100.00 |
0.00 |
750.00 |
6 |
9 |
40 |
||||
| 1997 |
11 |
1.80 |
1 |
0 |
2 |
8 |
0.00 |
200.00 |
800.00 |
4 |
4 |
50 |
||||
| 1998 |
37 |
2.00 |
11 |
5 |
5 |
16 |
45.45 |
45.45 |
145.45 |
6 |
10 |
38 |
||||
| 1999 |
18 |
2.70 |
0 |
0 |
0 |
18 |
7 |
11 |
39 |
|||||||
| 2000 |
NA |
|||||||||||||||
| 2001 |
41 |
2.40 |
7 |
4 |
3 |
27 |
57.14 |
42.86 |
385.71 |
9 |
18 |
33 |
||||
| 2002 |
55 |
2.50 |
22 |
5 |
6 |
22 |
22.73 |
27.27 |
100.00 |
7 |
15 |
32 |
||||
| Charley River |
1997 |
39 |
1.40 |
25 |
11 |
3 |
0 |
44.00 |
12.00 |
0.00 |
0 |
0 |
0 |
|||
| 1998 |
53 |
1.00 |
27 |
19 |
6 |
1 |
70.37 |
22.22 |
3.70 |
0 |
1 |
0 |
||||
| 1999 |
52 |
2.08 |
25 |
16 |
10 |
1 |
64.00 |
40.00 |
4.00 |
0 |
1 |
0 |
||||
| 2000 |
31 |
1.63 |
20 |
6 |
5 |
0 |
30.00 |
25.00 |
0.00 |
0 |
0 |
0 |
||||
| 2001 |
31 |
2.55 |
17 |
9 |
5 |
0 |
52.94 |
29.41 |
0.00 |
0 |
0 |
0 |
||||
| 2002 |
81 |
1.65 |
40 |
30 |
3 |
8 |
75.00 |
7.50 |
20.00 |
0 |
8 |
0 |
||||
| Cirque Lakes |
1983 |
66 |
26 |
10 |
9 |
21 |
38.46 |
34.62 |
80.77 |
10 |
11 |
48 |
||||
| 1984 |
27 |
4.80 |
16 |
4 |
8 |
1 |
25.00 |
50.00 |
6.25 |
0 |
1 |
0 |
||||
| 1990 |
107 |
2.50 |
47 |
15 |
19 |
26 |
31.91 |
40.43 |
55.32 |
13 |
13 |
50 |
||||
| 1993 |
58 |
2.50 |
38 |
9 |
1 |
10 |
23.68 |
2.63 |
26.32 |
0 |
10 |
0 |
||||
| 1994 |
63 |
2.60 |
21 |
9 |
9 |
24 |
42.86 |
42.86 |
114.29 |
3 |
21 |
13 |
||||
| 1995 |
76 |
3.20 |
27 |
9 |
11 |
29 |
33.33 |
40.74 |
107.41 |
7 |
22 |
24 |
||||
| 1997 |
77 |
3.20 |
42 |
13 |
3 |
19 |
30.95 |
7.14 |
45.24 |
5 |
14 |
26 |
||||
| 1998 |
62 |
2.10 |
18 |
9 |
3 |
32 |
50.00 |
16.67 |
177.78 |
7 |
25 |
22 |
||||
| 1999 |
69 |
3.65 |
33 |
13 |
15 |
8 |
39.39 |
45.45 |
24.24 |
3 |
5 |
38 |
||||
| 2000+ |
NA |
|||||||||||||||
| 2001 |
52 |
3.38 |
16 |
4 |
5 |
23 |
25.00 |
31.25 |
143.75 |
5 |
18 |
22 |
||||
| 2002 |
57 |
2.60 |
28 |
16 |
7 |
6 |
57.14 |
25.00 |
21.43 |
1 |
5 |
17 |
||||
| Total Counts |
Per 100 Ewes |
Rams |
||||||||||||||
| Survey Unit |
Year |
Total Sheep |
Survey Time |
Ewes |
Lambs |
Yearlings |
Rams |
Lambs |
Yearlings |
Rams |
Legal Rams |
Sublegal* |
% Legal |
|||
| Copper Mnt. |
1983 |
13 |
1 |
2 |
1 |
9 |
200.00 |
100.00 |
900.00 |
0 |
9 |
0 |
||||
| 1990 |
27 |
1.20 |
9 |
2 |
9 |
7 |
22.22 |
100.00 |
77.78 |
3 |
4 |
43 |
||||
| 1997 |
25 |
0.80 |
9 |
5 |
3 |
8 |
55.56 |
33.33 |
88.89 |
4 |
4 |
50 |
||||
| 1998 |
11 |
0.70 |
5 |
2 |
1 |
3 |
40.00 |
20.00 |
60.00 |
1 |
2 |
33 |
||||
| 1999 |
10 |
1.43 |
4 |
0 |
0 |
6 |
0.00 |
0.00 |
150.00 |
2 |
4 |
33 |
||||
| 2000 |
NA |
|||||||||||||||
| 2001 |
14 |
1.42 |
6 |
2 |
2 |
4 |
33.33 |
33.33 |
66.67 |
2 |
2 |
50 |
||||
| 2002 |
20 |
0.81 |
9 |
5 |
1 |
5 |
55.56 |
11.11 |
55.56 |
1 |
4 |
20 |
||||
| Glacier |
1993 |
84 |
42 |
10 |
32 |
23.81 |
76.19 |
3 |
29 |
9 |
||||||
| Mountain# |
1998 |
97 |
54 |
20 |
23 |
37.04 |
42.59 |
6 |
17 |
26 |
||||||
| 1999 |
76 |
40 |
15 |
21 |
37.50 |
52.50 |
4 |
16 |
19 |
|||||||
| 2000 |
100 |
61 |
6 |
33 |
9.84 |
54.10 |
6 |
27 |
18 |
|||||||
| Mount 5580 |
1997 |
24 |
0.50 |
10 |
6 |
5 |
3 |
60.00 |
50.00 |
30.00 |
0 |
3 |
0 |
|||
| 1998 |
35 |
0.40 |
17 |
11 |
3 |
4 |
64.71 |
17.65 |
23.53 |
0 |
4 |
0 |
||||
| 1999 |
20 |
0.52 |
10 |
5 |
5 |
0 |
50.00 |
50.00 |
0.00 |
0 |
0 |
0 |
||||
| 2000 |
27 |
0.47 |
12 |
4 |
7 |
4 |
33.33 |
58.33 |
33.33 |
1 |
3 |
25 |
||||
| 2001 |
32 |
0.52 |
13 |
6 |
5 |
8 |
46.15 |
38.46 |
61.54 |
2 |
6 |
25 |
||||
| 2002 |
29 |
0.50 |
17 |
4 |
4 |
4 |
23.53 |
23.53 |
23.53 |
3 |
1 |
75 |
||||
| Mount Harper# |
1982 |
87 |
39 |
8 |
40 |
20.51 |
0.00 |
102.56 |
18 |
22 |
45 |
|||||
| 1993 |
60 |
30 |
4 |
26 |
13.33 |
0.00 |
86.67 |
11 |
15 |
42 |
||||||
| 1997 |
83 |
40 |
9 |
5 |
29 |
22.50 |
12.50 |
72.50 |
13 |
16 |
45 |
|||||
| 2000 |
69 |
25 |
9 |
9 |
26 |
36.00 |
36.00 |
104.00 |
7 |
19 |
27 |
|||||
| Total Counts |
Per 100 Ewes |
Rams |
||||||||||||||
| Survey Unit |
Year |
Total Sheep |
Survey Time |
Ewes |
Lambs |
Yearlings |
Rams |
Lambs |
Yearlings |
Rams |
Legal Rams |
Sublegal* |
% Legal |
|||
| Mount |
1983 |
31 |
9 |
2 |
0 |
20 |
22.22 |
0.00 |
222.22 |
5 |
15 |
25 |
||||
| Sorenson |
1984 |
32 |
2.70 |
15 |
8 |
2 |
6 |
53.33 |
13.33 |
40.00 |
1 |
5 |
17 |
|||
| 1987 |
35 |
14 |
9 |
2 |
10 |
64.29 |
14.29 |
71.43 |
1 |
9 |
10 |
|||||
| 1990 |
58 |
1.90 |
18 |
12 |
7 |
21 |
66.67 |
38.89 |
116.67 |
2 |
19 |
10 |
||||
| 1993 |
16 |
1.40 |
0 |
0 |
0 |
16 |
5 |
11 |
31 |
|||||||
| 1994 |
48 |
1.50 |
17 |
6 |
0 |
25 |
35.29 |
0.00 |
147.06 |
6 |
19 |
24 |
||||
| 1995 |
57 |
1.30 |
20 |
17 |
6 |
15 |
85.00 |
30.00 |
75.00 |
5 |
10 |
33 |
||||
| 1997 |
79 |
1.10 |
46 |
17 |
15 |
1 |
36.96 |
32.61 |
2.17 |
1 |
0 |
100 |
||||
| 1998 |
35 |
1.00 |
15 |
7 |
2 |
11 |
46.67 |
13.33 |
73.33 |
7 |
4 |
64 |
||||
| 1999 |
98 |
1.33 |
55 |
21 |
9 |
13 |
38.18 |
16.36 |
23.64 |
6 |
7 |
46 |
||||
| 2000 |
NA |
|||||||||||||||
| 2001 |
97 |
1.37 |
59 |
15 |
19 |
4 |
25.42 |
32.20 |
6.78 |
2 |
2 |
50 |
||||
| 2002 |
71 |
1.10 |
35 |
18 |
9 |
9 |
51.43 |
25.71 |
25.71 |
1 |
8 |
11 |
||||
| Twin Mountain |
1983 |
35 |
12 |
10 |
3 |
11 |
83.33 |
25.00 |
91.67 |
1 |
10 |
9 |
||||
| 1990 |
48 |
1.50 |
15 |
13 |
4 |
16 |
86.67 |
26.67 |
106.67 |
0 |
16 |
0 |
||||
| 1997 |
54 |
1.20 |
23 |
11 |
4 |
16 |
47.83 |
17.39 |
69.57 |
4 |
12 |
25 |
||||
| 1998 |
49 |
0.80 |
23 |
10 |
6 |
10 |
43.48 |
26.09 |
43.48 |
3 |
7 |
30 |
||||
| 1999 |
62 |
0.53 |
22 |
10 |
6 |
24 |
45.45 |
27.27 |
109.09 |
6 |
18 |
25 |
||||
| 2000 |
62 |
1.03 |
22 |
8 |
4 |
28 |
36.36 |
18.18 |
127.27 |
6 |
22 |
21 |
||||
| 2001 |
27 |
0.68 |
3 |
3 |
0 |
21 |
100.00 |
0.00 |
700.00 |
7 |
14 |
33 |
||||
| 2002 |
17 |
0.63 |
3 |
2 |
0 |
12 |
66.67 |
0.00 |
400.00 |
5 |
7 |
42 |
||||
| Puzzle gulch/ |
1999 |
140 |
3.00 |
63 |
34 |
16 |
27 |
53.97 |
25.40 |
42.86 |
6 |
8 |
22 |
|||
| West point |
2000# |
179 |
82 |
16 |
32 |
49 |
19.51 |
39.02 |
59.76 |
19 |
30 |
39 |
||||
| 2001 |
131 |
2.97 |
67 |
22 |
9 |
33 |
32.84 |
13.43 |
49.25 |
9 |
24 |
27 |
||||
| 2002 |
118 |
2.85 |
62 |
21 |
9 |
26 |
33.87 |
14.52 |
41.94 |
6 |
20 |
23 |
||||
* “Sublegal” rams includes all rams with horns smaller than full curl.
+ A sheep survey was not completed at Cirque Lake during 2000.
# Surveys conducted by the Alaska Department of Fish and Game (Craig Gardner, Alaska Department of Fish and Game, personal communication).
Table B.1 Physical measurements of Dall’s sheep captured for radiocollaring in interior Alaska during March of 1999, 2000, 2001 and 2002. Dall’s sheep were captured at 2 general locations, Cirque Lake and West Point/Puzzle Gulch. Cirque Lake has mitigation measures intended to minimize the impacts of low-level military jet aircraft on Dall’s sheep and West Point/Puzzle Gulch does not.
| Right |
Left |
||||||||||||
| Sheep No. |
Capt. Date |
Wgt. (kg) |
Loc.1 |
Body Con. Score2 |
Horn length3* |
Horn length3* |
Right Annuli |
Left Annuli |
Meta-tarsal* |
Body* |
Chest Girth* |
Neck Circ. * |
Tooth wear |
| 1999 |
|||||||||||||
| 99-161 |
03/20 |
47.6 |
CL |
25.5 |
25 |
5 |
30.5 |
150 |
95 |
44 |
Light to mod. |
||
| 99-162 |
03/20 |
54.4 |
CL |
18 |
25 |
5 |
6 |
29 |
102 |
41 |
Light |
||
| 99-163 |
03/21 |
65.8 |
CL |
27.5 |
30 |
6 |
6 |
29 |
100 |
42 |
Light to mod. |
||
| 99-164 |
03/21 |
52.2 |
CL |
Brok. |
28 |
6 |
28 |
96.5 |
37 |
||||
| 99-165 |
03/21 |
47.6 |
CL |
18 |
18 |
6 |
5 |
27 |
96 |
37.5 |
Light |
||
| 99-166 |
03/21 |
45.4 |
CL |
20 |
25 |
7 |
7 |
28.5 |
98 |
37 |
Light |
||
| 99-167 |
03/22 |
56.7 |
WP |
18 |
18 |
4 |
4 |
28.5 |
103 |
39 |
Light to mod. |
||
| 99-168 |
03/22 |
63.5 |
WP |
32 |
33 |
9 |
7 |
29.5 |
104 |
44.5 |
Mod. To heavy |
||
| 99-169 |
03/21 |
43.1 |
CL |
27 |
28 |
7 |
7 |
27 |
92 |
38 |
Mod. |
||
| 99-170 |
03/22 |
63.5 |
WP |
24 |
26 |
6 |
7 |
28.5 |
102 |
42.5 |
Mod. To heavy |
||
| 99-171 |
03/19 |
61.2 |
WP |
31 |
31 |
8 |
29 |
151 |
108 |
46 |
Mod. |
||
| 99-172 |
03/23 |
65.8 |
WP |
24.5 |
21.5 |
5 |
5 |
28 |
102 |
40 |
Light |
||
| 99-173 |
03/22 |
65.8 |
WP |
36 |
35 |
8 |
8 |
28.3 |
108 |
46 |
Mod. To heavy |
||
| 99-174 |
03/19 |
61.2 |
WP |
27.5 |
26.5 |
6 |
6 |
27.5 |
157 |
104 |
45.5 |
Mod. |
|
| 99-175 |
03/21 |
59.0 |
CL |
21 |
Brok. |
6 |
28.5 |
100 |
38 |
Light |
|||
| 99-176 |
03/21 |
49.9 |
CL |
20 |
21 |
5 |
5 |
28 |
98 |
40 |
Light |
||
| 99-177 |
03/21 |
49.9 |
WP |
27 |
27 |
5 |
5 |
28 |
104 |
38.5 |
Light to mod. |
||
| 99-178 |
03/22 |
65.8 |
WP |
28 |
30.5 |
8 |
8 |
28.3 |
47 |
Mod. To heavy |
|||
| 99-179 |
03/21 |
62.1 |
WP |
26.5 |
26 |
6 |
6 |
28.2 |
109 |
48 |
Mod. |
||
| 99-180 |
03/20 |
54.4 |
CL |
29 |
21 |
7 |
7 |
28.5 |
100 |
40 |
Light |
||
| 2000 |
|||||||||||||
| 00-161 |
03/16 |
59.0 |
WP |
R2.5/B3/P2 |
31 |
33 |
7 |
7 |
28 |
151 |
110 |
39 |
Light |
| 00-162 |
03/16 |
61.2 |
WP |
R2.5/B2/P2 |
24 |
25 |
7 |
8 |
28 |
145 |
104 |
40 |
Heavy |
| 00-163 |
03/16 |
47.6 |
WP |
R3.5/B3.5/P2.5 |
22 |
20.5 |
5 |
5 |
29 |
147 |
96 |
43 |
Light |
| 00-164 |
03/16 |
61.2 |
WP |
R2/B2/P2 |
26 |
24 |
8 |
8 |
29 |
152 |
108 |
39 |
Light |
| 00-165 |
03/16 |
65.8 |
WP |
R3/B3/P2.5 |
30 |
28.5 |
8 |
8 |
30 |
154 |
127 |
42 |
Light |
| 00-166 |
03/16 |
63.5 |
WP |
R3.5/B3.5/P2.5 |
29 |
31 |
9 |
8 |
30 |
168 |
109 |
39 |
Heavy |
| Right |
Left |
||||||||||||
| Sheep No. |
Capt. Date |
Wgt. (kg) |
Loc.1 |
Body Con. Score2 |
Horn length3* |
Horn length3* |
Right Annuli |
Left Annuli |
Meta-tarsal* |
Body* |
Chest Girth* |
Neck Circ. * |
Tooth wear |
| 00-167 |
03/16 |
WP |
R3/B2.5/P2 |
24 |
26 |
5 |
6 |
29 |
153 |
103 |
41 |
Light |
|
| 00-168 |
03/16 |
52.2 |
WP |
R3/B3/P2.5 |
25 |
29.5 |
6 |
5 |
29 |
151 |
113 |
43 |
Light |
| 00-169 |
03/16 |
49.9 |
WP |
R2.5/B2.5/P2 |
19.5 |
22 |
4 |
4 |
30 |
148 |
106 |
41 |
Light |
| 00-170 |
03/16 |
61.2 |
WP |
R3/B3/P2.5 |
24.5 |
23 |
4 |
4 |
29 |
145 |
107 |
42.5 |
Mod. |
| 00-171 |
03/15 |
54.4 |
CL |
R3/B3/P2.5 |
18.5 |
21 |
6 |
6 |
30 |
158 |
101 |
37 |
Heavy |
| 00-172 |
03/15 |
49.9 |
CL |
R2/B2/P2 |
28 |
31 |
9 |
9 |
30 |
109 |
41 |
Heavy |
|
| 00-173 |
03/17 |
36.3 |
CL |
R3.5/B3.5/P2.5 |
16 |
15 |
2 |
1 |
29 |
141 |
100 |
38 |
Light |
| 00-174 |
03/15 |
54.4 |
CL |
R2.5/B2/P2 |
30 |
22.5 |
9 |
7 |
29 |
152 |
104 |
40 |
Mod. |
| 00-175 |
03/14 |
49.9 |
CL |
R2/B2/P2 |
22 |
29 |
9 |
8 |
29 |
104 |
39 |
Light |
|
| 00-176 |
03/15 |
56.7 |
CL |
R3.5/B3.5/P3 |
34 |
33.5 |
9 |
9 |
29 |
149 |
102 |
43 |
Light |
| 00-177 |
03/15 |
43.1 |
CL |
R2.5/B2/P2 |
24 |
24 |
6 |
5 |
30 |
149 |
101 |
43 |
Mod. |
| 00-178 |
03/14 |
49.9 |
CL |
R2.5/B3/P2 |
25 |
22.5 |
4 |
4 |
28 |
100 |
40.5 |
Mod. |
|
| 00-179 |
03/15 |
52.2 |
CL |
R2.5/B2/P2 |
10.5 |
28 |
Brok. |
7/broo |
30 |
154 |
105 |
39 |
Heavy |
| 00-180 |
03/14 |
52.2 |
CL |
23 |
22 |
5 |
5 |
30 |
102 |
36 |
Light |
||
| 2001 |
|||||||||||||
| 01-161 |
03/03 |
54.4 |
WP |
R3/B3/P3 |
21.5 |
23.5 |
6 |
7 |
28.5 |
147 |
101 |
40 |
Light to mod. |
| 01-162 |
03/03 |
WP |
R3.5/B3/P3 |
23.5 |
25 |
6 |
6 |
28 |
148 |
99 |
38 |
Mod. |
|
| 01-163 |
03/03 |
54.4 |
WP |
R3/B3/P2.5 |
22 |
28 |
7 |
7 |
28 |
157 |
103 |
41 |
Light |
| 01-164 |
03/02 |
49.9 |
CL |
R2.5/B2/P2 |
25 |
22.5 |
7 |
6 |
27 |
144 |
103.5 |
35 |
Mod. |
| 01-165 |
03/03 |
61.2 |
WP |
R2.5/B2.5/P2 |
30 |
27 |
7 |
6 |
29 |
152 |
110 |
36 |
Mod. |
| 01-166 |
03/02 |
56.7 |
CL |
R3/B2.5/P2.5 |
31 |
29 |
7 |
7 |
28 |
140 |
105 |
40 |
Light to mod. |
| 01-167 |
03/02 |
47.6 |
CL |
R2.5/B3/P2 |
25 |
24 |
5 |
6 |
31 |
150 |
109 |
42 |
Light |
| 01-168 |
03/03 |
59.0 |
WP |
R3.5/B3.5/P3 |
29 |
30.5 |
7 |
6 |
29 |
147 |
105 |
42 |
Mod. |
| 01-169 |
03/03 |
45.8 |
WP |
R2.5/B3/P2.5 |
21 |
19.5 |
28 |
153 |
98 |
38 |
Light to mod. |
||
| 01-170 |
03/03 |
54.4 |
WP |
R2.5/B2.5/P2.5 |
32.5 |
32 |
9 |
9 |
28 |
145 |
111 |
37 |
Mod. |
| 01-171 |
03/06 |
SB |
R2.5/B2.5/P2.5 |
10.5 |
16 |
Brok. |
3 |
26.5 |
151 |
96 |
38 |
Light |
|
| 01-172 |
03/03 |
59.0 |
WP |
R3.5/B3/P2.5 |
27 |
26 |
7 |
6 |
29 |
159 |
112 |
39 |
Mod. |
| 01-173 |
03/02 |
52.2 |
WP |
R2.5/B2/P2 |
28 |
28 |
6 |
6 |
27.5 |
153 |
106 |
42 |
Heavy |
| 01-175 |
03/04 |
CL |
R3.5/B3.5/P3 |
26.5 |
25 |
7 |
6 |
27 |
135 |
108 |
42 |
Mod. |
|
| 01-176 |
03/06 |
57.2 |
SB |
R3/B2.5/P2.5 |
27 |
23 |
7 |
7 |
153 |
107 |
42 |
Light |
|
| 01-177 |
03/04 |
CL |
R3.5/B3.5/P3 |
25.5 |
25 |
5 |
6 |
26.5 |
150 |
105 |
44 |
Mod. |
|
| 01-178 |
03/02 |
52.2 |
WP |
R3/B2.5/P2.5 |
23 |
22 |
5 |
5 |
28 |
149 |
103 |
36.5 |
Mod. |
| 01-179 |
03/04 |
59.0 |
CL |
R3/B3.5/P3 |
31 |
Brok. |
6 |
Brok. |
28 |
142 |
110 |
44 |
Mod. to heavy |
| 01-180 |
03/04 |
61.2 |
CL |
R3.5/B3.5/P3 |
21 |
25 |
6 |
6 |
29 |
154 |
112 |
43 |
Heavy |
| Right |
Left |
||||||||||||
| Sheep No. |
Capt. Date |
Wgt. (kg) |
Loc.1 |
Body Con. Score2 |
Horn length3* |
Horn length3* |
Right Annuli |
Left Annuli |
Meta-tarsal* |
Body* |
Chest Girth* |
Neck Circ. * |
Tooth wear |
| 2002 |
|||||||||||||
| 02_161 |
03/14 |
61.2 |
CL |
R2/B2.5/P2 |
25.5 |
25 |
9 |
9 |
27 |
158 |
107 |
37 |
Light |
| 02_162 |
03/14 |
61.2 |
CL |
R3/B3/P3 |
26 |
27 |
4 |
4 |
29 |
153 |
111 |
42 |
Mod. |
| 02_163 |
03/14 |
54.4 |
WP |
R3.5/B3/P3 |
21 |
23 |
3 |
3 |
27.5 |
149 |
108 |
40 |
Light |
| 02_164 |
03/13 |
65.8 |
CL |
R3/B2.5/P2.5 |
24 |
25 |
7 |
8 |
28.5 |
161 |
112 |
44 |
Mod. |
| 02_165 |
03/13 |
56.7 |
WP |
R2.5/B2.5/P2 |
26 |
25 |
8 |
7 |
27.5 |
165 |
107 |
44.5 |
Light |
| 02_166 |
03/14 |
47.6 |
CL |
R2/B2.5/P2 |
21 |
23 |
7 |
7 |
26.5 |
147 |
102.5 |
39 |
Mod. |
| 02_167 |
03/14 |
59.0 |
WP |
R3/B3/P3 |
20 |
22 |
6 |
6 |
28 |
160 |
105 |
43 |
Light |
| 02_168 |
03/14 |
65.8 |
CL |
R3/B3/P2.5 |
23 |
24 |
7 |
7 |
30 |
147 |
113 |
39 |
Mod. |
| 02_169 |
03/13 |
56.7 |
WP |
R3/B2.5/P2.5 |
27.5 |
26 |
5 |
6 |
28.5 |
155 |
112 |
43 |
Mod. |
| 02_170 |
03/14 |
59.0 |
CL |
R3/B3/P3 |
27.2 |
28 |
9 |
8 |
29 |
157 |
109 |
35 |
Mod. |
| 02_171 |
03/13 |
59.0 |
WP |
R3/B3/P2.5 |
27 |
24 |
9 |
9 |
27.5 |
153 |
113 |
44 |
Mod. |
| 02_172 |
03/13 |
56.7 |
WP |
R2.5/B2.5/P2 |
22 |
23 |
7 |
7 |
28 |
159 |
110.5 |
45 |
Mod. |
| 02_173 |
03/12 |
49.9 |
CL |
R2/B2.5/P2.5 |
24 |
24 |
8 |
8 |
27 |
103.5 |
36.5 |
Light |
|
| 02_174 |
03/12 |
54.4 |
CL |
R3/B3/P3 |
25 |
23 |
6 |
5 |
28 |
129 |
103 |
35 |
Mod. |
| 02_175 |
03/14 |
56.7 |
CL |
R2.5/B2/P2 |
32 |
Brok. |
6 |
Brok. |
27 |
155 |
107 |
41.4 |
Mod. |
| 02_176 |
03/13 |
65.8 |
WP |
R3/B3/P3 |
29.5 |
28.5 |
10 |
10 |
30 |
157 |
114 |
36 |
Mod. |
| 02_177 |
03/13 |
54.4 |
WP |
R3/B3.5/P3 |
25 |
26 |
7 |
8 |
28 |
150 |
110 |
38.5 |
Light |
| 02_178 |
03/14 |
65.8 |
CL |
R3/B3/P2.5 |
29.5 |
30 |
10 |
10 |
28.5 |
162 |
112 |
47 |
Heavy |
| 02_179 |
03/13 |
47.6 |
WP |
R3/B3/P3 |
21 |
21 |
6 |
6 |
26.5 |
152 |
102 |
42.5 |
Light |
| 02_180 |
03/12 |
CL |
R2.5/B2/P2.5 |
26 |
25.5 |
8 |
6 |
27.5 |
156 |
106 |
43 |
Light |
1 CL = Cirque Lake, WP = West Point/Puzzle Gulch, SB = Sheep bluff, a known sheep area in close proximity to Cirque Lake.
2 Body condition scores were determined by palpating animals at: 1) Ribs (R); 2) Back/withers (B); and 3) hip-pin (P) or rump. Scores were a subjective rating from 1 to 5 (1 = emaciated, 5 = obese).
3 Brok. = Horn broken, Broo = horn broomed on tip.
* Length, girth and circumference were measured in cm.
Table C.1. Incidental mammal and bird species observed (or tracks observed) while watching Dall’s sheep (Ovis dalli) in February, March, April and May of 2000, and during March, May June and July of 2001.
| MOA SHEEP PROJECT 2000 |
|||
| Animals/Tracks Observed |
Cirque Lakes |
West Point |
|
| Mammals |
|||
| Caribou (Rangifer tarandus) |
Feb, May |
||
| Dall’s sheep (Ovis dalli) |
Feb, April, May, July |
Feb, April, May, July |
|
| Fox (Vulpes vulpes) |
Feb |
Feb, May |
|
| Grizzly Bear (Ursus arctos) |
May |
May |
|
| Hoary Marmot (Marmota caligata) |
May, July |
May |
|
| Marten (Martes americana) |
Feb |
||
| Moose (Alces alces) |
May |
||
| Otter (Lontra Canadensis) |
Feb |
||
| Pika (Ochotona collaris) |
Feb, April, May, July |
Feb, May |
|
| Red Squirrel (Tamiasciurus hudsonicus) |
Feb, April |
||
| Ermine (Mustela erminea) |
May |
||
| Snowshoe Hare (Lepus americanus) |
Feb, May |
||
| Wolf (Canis lupus) |
Feb |
Feb, April |
|
| Wolverine (Gulo gulo) |
Feb, April |
Feb, April, May |
|
| Birds |
|||
| American Robin |
May |
May |
|
| American tree-sparrow |
May, July |
May |
|
| Boreal Chickadee |
Feb |
May |
|
| Common Raven |
April, May, July |
||
| Common Red polls |
May, July |
May |
|
| Common Snipe |
May |
May |
|
| Evening Grosbeak |
May |
||
| Fox Sparrow |
May |
May |
|
| Golden Eagle |
May |
||
| Gray -headed junco |
May |
||
| Gray Jay |
April |
May |
|
| Gray-cheeked thrush |
May |
||
| Gray-crowned rosey finch |
May, July |
May |
|
| Gyrfalcon |
Feb., April, May |
Feb, May |
|
| Hermit Thrush |
May |
||
| Horned Lark |
July |
||
| Lapland Longspur |
May, July |
||
| Long-tailed duck |
July |
||
| Northern harrier |
May |
May |
|
| Northern Shrike |
May |
||
| Northern Wheatear |
July |
May |
|
| Osprey |
July |
||
| Animals/Tracks Observed |
Cirque Lakes |
West Point |
|
| Birds |
|||
| Rock Ptarmigan |
Feb., April |
Feb, May |
|
| Ruby-Crowned kinglet |
May |
||
| Savannah Sparrow |
May |
||
| Say's phoebe |
May |
||
| Scaup sps. |
July |
||
| Scoter sps. |
July |
||
| Townsend Solitaire |
May |
May |
|
| Upland Sandpiper |
May |
||
| Varied thrush |
May |
||
| Water pipit |
May, July |
May |
|
| White winged crossbill |
April |
||
| White-crowned Sparrow |
May, July |
May |
|
| White-winged scoter |
July |
||
| Willow Ptarmigan |
Feb., April |
||
| Yellow-rumped warbler |
May |
||
| MOA SHEEP PROJECT 2001 |
|||
| Animals/Tracks Observed |
Cirque Lakes |
West Point |
|
| Mammals |
|||
| Black Bear (Ursus americanus) |
May |
||
| Caribou (Rangifer tarandus) |
May |
July |
|
| Dall’s sheep (Ovis dalli) |
March, May, June, July |
March, May, June, July |
|
| Fox (Vulpes vulpes) |
March |
||
| Grizzly Bear (Ursus arctos) |
May, June |
May |
|
| Hoary Marmot (Marmota caligata) |
May |
||
| Lynx (Lynx canadensis) |
May |
||
| Moose (Alces alces) |
March |
||
| Pika (Ochotona collaris) |
May |
March |
|
| Red -backed vole (Clethrionomys rutilus) |
May |
||
| Ermine (Mustela erminea) |
May |
||
| Wolf (Canis lupus) |
May |
||
| Wolverine (Gulo gulo) |
March, May, June, July |
March, May, June, July |
|
| Birds |
|||
| American Robin |
May |
||
| American tree-sparrow |
May |
||
| Bohemian Wax-wing |
May |
||
| Bonaparte's Gull |
July |
||
| Boreal Chickadee |
March |
||
| Boreal Owl |
May |
||
| Common Raven |
May |
March |
|
| Animals/Tracks Observed |
Cirque Lakes |
West Point |
|
| Birds |
|||
| Common Red polls |
May |
March |
|
| Flicker |
May |
||
| Fox Sparrow |
May |
||
| Golden Eagle |
May |
May |
|
| Goshawk |
March |
||
| Gray -headed junco |
May |
||
| Gray Jay |
May |
March |
|
| Gray-crowned rosey finch |
May |
||
| Gyrfalcon |
May |
||
| Horned Lark |
May |
||
| Lapland Longspur |
May |
||
| Long-tailed duck |
July |
||
| Merlin |
May |
||
| Northern harrier |
May |
||
| Red-necked phalarope |
July |
||
| Rock Ptarmigan |
May |
March |
|
| Rough-legged hawk |
May |
||
| Ruby-Crowned kinglet |
May |
||
| Say's phoebe |
May |
||
| Scaup sps. |
July |
||
| Scoter sps. |
July |
||
| Townsend Solitaire |
May |
||
| Water pipit |
May |
||
| White-crowned Sparrow |
May |
||
| White-winged scoter |
July |
||
| Yellow-rumped warbler |
May |
||
Results from microhistological (Tables D.1-D.4) and nitrogen analysis (D.5) of sheep pellets in 2 study areas in the Yukon-Tanana Uplands, Alaska. Microhistological analysis was conducted by the Wildlife Habitat Nutrition Laboratory, University of Washington, Pullman, WA. Proportion of plant composition of fecal pellets was determined at a plant species level using 4 slides per sample and by looking at 25 views per slide. Nitrogen content of fecal pellets was determined by the the Chemical Nutrition Laboratory, University of Alaska, Fairbanks, Alaska. Nitrogen content was determined by combustion in a LECO auto-analyzer.
Table D.1. Percent occurrence of plant species and parts in microhistological samples of fecal pellets from Dall's sheep, by study area and month in the Yukon-Tanana Uplands, Alaska, 2000.| Cirque Lake |
West Point |
||||||||
| Plants |
Feb. |
April |
May |
July |
Feb. |
April |
May |
July |
|
| Betula stem |
0.8 |
||||||||
| Dryas leaf |
1.9 |
0.7 |
2.4 |
1.0 |
2.4 |
4.1 |
1.1 |
||
| Dryas stem |
2.0 |
0.3 |
1.2 |
0.6 |
0.5 |
||||
| Ledum |
0.5 |
0.2 |
0.5 |
0.3 |
|||||
| Populus leaf |
1.1 |
||||||||
| Rhododendron |
1.9 |
1.9 |
|||||||
| Rosa leaf |
0.5 |
||||||||
| Rosa stem |
0.5 |
||||||||
| Rubus discolor |
0.1 |
||||||||
| Salix leaf/hair |
0.4 |
0.5 |
1.1 |
3.2 |
|||||
| Salix stem |
0.8 |
1.4 |
1.2 |
0.4 |
0.8 |
1.4 |
2.5 |
0.3 |
|
| Vaccinium leaf |
1.4 |
0.8 |
0.8 |
||||||
| Vaccinium stem |
0.8 |
||||||||
| Total Shrubs |
2.7 |
3.2 |
8.2 |
0.6 |
3.4 |
7.4 |
11.8 |
7.0 |
|
| Agropyron |
1.3 |
1.1 |
3.2 |
0.6 |
0.8 |
2.4 |
1.6 |
1.1 |
|
| Arctogrostis |
1.6 |
||||||||
| Calamagrostis purpurascens |
1.6 |
4.1 |
2.2 |
0.8 |
2.8 |
0.7 |
1.1 |
2.7 |
|
| Festuca altaica |
11.0 |
14.5 |
8.0 |
7.3 |
16.8 |
9.2 |
18.6 |
5.9 |
|
| Hierochloe alpina |
1.9 |
3.7 |
1.6 |
0.4 |
1.7 |
1.6 |
0.3 |
||
| Poa spp. |
9.4 |
7.8 |
6.2 |
6.7 |
7.6 |
8.4 |
11.5 |
4.9 |
|
| Other Grasses |
0.5 |
3.2 |
2.4 |
1.5 |
3.6 |
1.9 |
|||
| Total Grasses |
25.2 |
31.7 |
24.4 |
19.8 |
29.5 |
26.0 |
36.3 |
14.9 |
|
| Carex bigelowii |
5.4 |
5.3 |
2.2 |
25.8 |
1.0 |
3.1 |
4.7 |
23.2 |
|
| Carex microchaeta |
0.3 |
1.1 |
|||||||
| Carex spp. |
8.9 |
7.1 |
2.0 |
14.3 |
1.3 |
3.9 |
2.2 |
12.7 |
|
| Eriophorum |
1.0 |
||||||||
| Juncus/Luzula |
1.6 |
0.4 |
24.2 |
0.5 |
1.0 |
1.1 |
22.9 |
||
| Total Sedge/Rush |
16.2 |
13.5 |
5.6 |
64.3 |
2.8 |
8.0 |
8.0 |
58.8 |
|
| Arabis hirsuta |
0.5 |
0.3 |
0.2 |
||||||
| Artemisia spp. |
0.4 |
||||||||
| Cirque Lake |
West Point |
||||||||
| Plants |
Feb. |
April |
May |
July |
Feb. |
April |
May |
July |
|
| Astragalus |
1.2 |
0.6 |
|||||||
| Equisetum |
0.5 |
||||||||
| Lupinus/Lotus |
1.7 |
0.3 |
2.7 |
||||||
| Silene menziesii |
4.2 |
0.5 |
0.6 |
||||||
| Other Forbs |
0.3 |
0.5 |
0.2 |
1.4 |
1.7 |
0.3 |
|||
| Total Forbs |
0.8 |
1.0 |
4.7 |
2.0 |
0.5 |
4.6 |
1.8 |
2.7 |
|
| Alectoria/Bryoria |
1.9 |
1.0 |
0.8 |
1.3 |
0.5 |
||||
| Cetraria/Dactylina |
3.5 |
3.0 |
11.5 |
0.4 |
1.5 |
5.6 |
5.5 |
1.6 |
|
| Cladina/Cladonia |
4.9 |
5.5 |
12.5 |
3.0 |
7.9 |
3.9 |
6.0 |
0.5 |
|
| Peltigera |
9.2 |
6.2 |
4.8 |
2.8 |
5.6 |
7.0 |
3.8 |
9.4 |
|
| Other Lichen |
1.0 |
||||||||
| Total Lichen |
19.5 |
14.7 |
30.8 |
7.0 |
16.3 |
16.5 |
15.3 |
12.0 |
|
| Aulacomnium |
7.0 |
5.3 |
3.4 |
0.6 |
3.1 |
1.2 |
4.4 |
1.9 |
|
| Classic Moss* |
22.9 |
26.5 |
21.3 |
5.5 |
44.1 |
35.3 |
21.6 |
2.7 |
|
| Polytrichum |
5.7 |
3.9 |
1.6 |
0.3 |
1.0 |
0.8 |
|||
| Sphagnum |
0.2 |
0.2 |
|||||||
| Total Mosses |
35.6 |
35.9 |
26.3 |
6.3 |
47.5 |
37.5 |
26.8 |
4.6 |
|
| TOTAL |
100.0 |
100.0 |
100.0 |
100.0 |
100.0 |
100.0 |
100.0 |
100.0 |
|
* Classic moss includes Dicranum, Bryum, Hypnum, Pohlia and several other mosses that are difficult to differentiate in microhistological samples.
Table D.2. Percent occurrence of plant species and parts in microhistological samples of fecal pellets from Dall's sheep, by study area and month in the Yukon-Tanana Uplands, Alaska, 2001.| Cirque Lake |
West Point |
|||||||
| Plants: |
March |
May |
June |
July |
March |
June |
July |
|
| Arctostaphylos alpina stem |
||||||||
| Artemisia spp. |
0.5 |
0.1 |
||||||
| Betula nana stem |
0.9 |
|||||||
| Dryas octopetala leaf |
0.3 |
3.7 |
0.1 |
0.4 |
5.4 |
1.4 |
||
| Dryas octopetala stem |
1.1 |
1.0 |
0.7 |
|||||
| Empetrum nigrum leaf |
0.9 |
1.4 |
||||||
| Ledum palustre leaf |
0.9 |
0.7 |
0.5 |
0.2 |
0.2 |
|||
| Rhododendron lapponicum leaf |
0.6 |
0.7 |
||||||
| Rosa acicularis stem |
0.6 |
0.5 |
||||||
| Salix spp. leaf |
3.3 |
0.5 |
0.6 |
2.0 |
2.4 |
|||
| Salix spp. leaf/catkin |
0.5 |
|||||||
| Salix spp. stem |
2.4 |
2.3 |
1.4 |
1.1 |
1.8 |
0.2 |
||
| Vaccinium spp. leaf |
1.4 |
|||||||
| Vaccinium spp. stem |
0.6 |
0.7 |
||||||
| Shrub leaf |
0.2 |
0.6 |
||||||
| Shrub stem |
0.1 |
0.4 |
1.0 |
0.7 |
||||
| Total Shrubs |
5.0 |
6.1 |
12.2 |
2.3 |
3.9 |
12.1 |
5.4 |
|
| Agropyron spicatum |
0.4 |
1.0 |
1.0 |
1.1 |
2.6 |
1.8 |
1.1 |
|
| Calamagrostis purpurascens |
1.9 |
3.3 |
6.1 |
2.7 |
5.5 |
10.5 |
7.1 |
|
| Festuca altaica |
10.0 |
8.4 |
17.3 |
10.1 |
26.6 |
16.0 |
27.2 |
|
| Hierochloe alpina |
2.6 |
1.6 |
1.1 |
1.5 |
4.3 |
0.2 |
||
| Poa spp. |
8.6 |
7.1 |
14.7 |
6.6 |
14.7 |
8.5 |
11.0 |
|
| Unkown Grasses |
0.2 |
1.6 |
3.7 |
1.6 |
2.6 |
4.5 |
1.6 |
|
| Total Grasses |
21.1 |
24.0 |
44.4 |
23.2 |
53.5 |
45.6 |
48.2 |
|
| Carex bigelowii |
7.7 |
1.9 |
7.0 |
19.9 |
3.4 |
4.0 |
4.8 |
|
| Carex spp. |
18.8 |
9.4 |
21.9 |
28.9 |
5.3 |
8.0 |
15.5 |
|
| Eriophorum spp. |
0.6 |
|||||||
| Luzula/Juncus |
4.9 |
5.6 |
3.3 |
11.5 |
5.3 |
3.8 |
9.1 |
|
| Total Sedges/Rushes |
31.4 |
16.9 |
32.2 |
60.3 |
14.6 |
15.8 |
29.4 |
|
| Antennaria friesiana |
3.8 |
0.1 |
||||||
| Arabis hirsuta |
0.2 |
|||||||
| Astragalus/Oxytropis |
0.2 |
0.1 |
0.5 |
0.9 |
||||
| Equisetum spp. |
0.5 |
0.4 |
||||||
| Lupinus spp. |
0.4 |
0.4 |
0.4 |
0.2 |
1.5 |
|||
| Polygonum spp. |
1.0 |
|||||||
| Potentilla spp. |
0.5 |
1.5 |
||||||
| Saxifraga spp. |
0.6 |
1.0 |
0.2 |
|||||
| Silene menziesii |
0.4 |
|||||||
| Unknown Forbs |
0.4 |
0.7 |
1.6 |
0.1 |
0.8 |
2.0 |
||
| Total Forbs |
1.0 |
2.5 |
6.1 |
0.8 |
1.3 |
2.4 |
6.3 |
|
| Cirque Lake |
West Point |
|||||||
| Plants: |
March |
May |
June |
July |
March |
June |
July |
|
| Alectoria/Bryoria/Usnea |
1.7 |
1.6 |
0.9 |
1.4 |
1.3 |
3.0 |
0.9 |
|
| Cetraria/Dactilina |
2.1 |
5.4 |
0.9 |
2.5 |
2.1 |
5.3 |
2.0 |
|
| Cladonia/Cladina |
6.4 |
11.2 |
2.4 |
3.0 |
4.9 |
2.3 |
0.7 |
|
| Foliose Lichen (Peltigera type) |
7.3 |
4.0 |
2.2 |
4.7 |
1.2 |
5.1 |
||
| Total Lichen |
17.5 |
22.2 |
4.2 |
9.1 |
13.0 |
11.8 |
8.7 |
|
| Aulacomium moss |
0.2 |
1.0 |
1.3 |
1.5 |
||||
| Classic moss |
11.8 |
9.1 |
3.0 |
9.4 |
8.0 |
2.0 |
||
| Dicranum moss |
6.8 |
13.4 |
0.2 |
2.6 |
2.3 |
|||
| Polytrichum moss |
3.9 |
3.5 |
0.2 |
2.0 |
||||
| Selaginella sibirica |
0.7 |
|||||||
| Sphagnum spp. moss |
1.3 |
1.0 |
||||||
| Unknown Moss |
0.3 |
|||||||
| Total Mosses |
24.0 |
28.3 |
0.9 |
4.3 |
13.7 |
12.3 |
2.0 |
|
| TOTAL |
100.00 |
100.00 |
100.00 |
100.00 |
100.00 |
100.00 |
100.00 |
|
* Classic moss includes Dicranum, Bryum, Hypnum, Pohlia and several other mosses that are difficult to differentiate in microhistological samples.
Table D.3. Percent occurrence of plant species and parts in microhistological samples of fecal pellets from Dall's sheep, by study area and month in the Yukon-Tanana Uplands, Alaska, 2002.| Cirque Lake |
West Point |
||
| Plants: |
March |
March |
|
| Arctostaphylos alpina stem |
1.4 |
||
| Artemisia spp. |
1.3 |
||
| Betula nana stem |
|||
| Dryas octopetala leaf |
0.2 |
0.6 |
|
| Dryas octopetala stem |
|||
| Empetrum nigrum leaf |
|||
| Ledum palustre leaf |
1.4 |
||
| Rhododendron lapponicum leaf |
0.8 |
||
| Rosa acicularis stem |
0.8 |
||
| Salix spp. leaf |
1.1 |
||
| Salix spp. leaf/catkin |
|||
| Salix spp. stem |
0.8 |
0.3 |
|
| Vaccinium spp. leaf |
|||
| Vaccinium spp. stem |
|||
| Shrub leaf |
0.5 |
||
| Shrub stem |
|||
| Total Shrubs |
3.1 |
6.1 |
|
| Agropyron spicatum |
2.3 |
1.4 |
|
| Calamagrostis purpurascens |
4.0 |
3.3 |
|
| Festuca altaica |
14.6 |
19.7 |
|
| Hierochloe alpina |
0.5 |
0.6 |
|
| Poa spp. |
6.8 |
3.6 |
|
| Unkown Grasses |
2.3 |
2.5 |
|
| Total Grasses |
30.5 |
31.1 |
|
| Carex bigelowii |
2.8 |
3.0 |
|
| Carex spp. |
8.3 |
5.0 |
|
| Eriophorum spp. |
|||
| Luzula/Juncus |
7.3 |
4.4 |
|
| Total Sedges/Rushes |
18.4 |
12.4 |
|
| Antennaria friesiana |
|||
| Arabis hirsuta |
|||
| Astragalus/Oxytropis |
0.2 |
0.3 |
|
| Equisetum spp. |
|||
| Lupinus spp. |
1.5 |
||
| Polygonum spp. |
|||
| Potentilla spp. |
0.6 |
||
| Saxifraga spp. |
0.3 |
||
| Silene menziesii |
|||
| Unknown Forbs |
0.8 |
0.6 |
|
| Total Forbs |
2.5 |
1.8 |
|
| Cirque Lake |
West Point |
||
| Plants: |
March |
March |
|
| Alectoria/Bryoria/Usnea |
2.5 |
3.6 |
|
| Cetraria/Dactilina |
4.0 |
1.7 |
|
| Cladonia/Cladina |
3.5 |
3.6 |
|
| Foliose Lichen (Peltigera type) |
5.0 |
5.8 |
|
| Total Lichen |
15.0 |
14.7 |
|
| Aulacomium moss |
0.8 |
0.6 |
|
| Classic moss |
17.1 |
30.8 |
|
| Dicranum moss |
6.3 |
1.4 |
|
| Polytrichum moss |
5.0 |
1.1 |
|
| Selaginella sibirica |
|||
| Sphagnum spp. moss |
|||
| Unknown Moss |
1.3 |
||
| Total Mosses |
30.5 |
33.9 |
|
| TOTAL |
100.00 |
100.00 |
* Classic moss includes Dicranum, Bryum, Hypnum, Pohlia and several other mosses that are difficult to differentiate in microhistological samples.
| Forage |
Cirque Lakes |
West Point |
||||||||||||
| Group |
February |
March |
April |
May |
June |
July |
February |
March |
April |
May |
June |
July |
||
| Shrubs |
2.7 |
3.2 |
8.2 |
0.6 |
3.4 |
7.4 |
11.8 |
7.0 |
||||||
| Grasses |
25.2 |
31.7 |
24.4 |
19.8 |
29.5 |
26.0 |
36.3 |
14.9 |
||||||
| Sedges/Rushes |
16.2 |
13.5 |
5.6 |
64.3 |
2.8 |
8.0 |
8.0 |
58.8 |
||||||
| Forbs |
0.8 |
1.0 |
4.7 |
2.0 |
0.5 |
4.6 |
1.8 |
2.7 |
||||||
| Lichens |
19.5 |
14.7 |
30.8 |
7.0 |
16.3 |
16.5 |
15.3 |
12.0 |
||||||
| Mosses |
35.6 |
35.9 |
26.3 |
6.3 |
47.5 |
37.5 |
26.8 |
4.6 |
||||||
| Shrubs |
5.0 |
6.1 |
12.2 |
2.3 |
3.9 |
12.1 |
5.4 |
|||||||
| Grasses |
21.1 |
24.0 |
44.4 |
23.2 |
53.5 |
45.6 |
48.2 |
|||||||
| Sedges/Rushes |
31.4 |
16.9 |
32.2 |
60.3 |
14.6 |
15.8 |
29.4 |
|||||||
| Forbs |
1.0 |
2.5 |
6.1 |
0.8 |
1.3 |
2.4 |
6.3 |
|||||||
| Lichens |
17.5 |
22.2 |
4.2 |
9.1 |
13.0 |
11.8 |
8.7 |
|||||||
| Moss |
24.0 |
28.3 |
0.9 |
4.3 |
13.7 |
12.3 |
2.0 |
|||||||
| Shrubs |
3.1 |
6.1 |
||||||||||||
| Grasses |
30.5 |
31.1 |
||||||||||||
| Sedges/Rushes |
18.4 |
12.4 |
||||||||||||
| Forbs |
2.5 |
1.8 |
||||||||||||
| Lichens |
15.0 |
14.7 |
||||||||||||
| Moss |
30.5 |
33.9 |
||||||||||||
| 2000 |
2001 |
||||
| Month |
Cirque Lakes |
West Point |
Cirque Lakes |
West Point |
|
| February |
1.62 |
1.47 |
|||
| March |
1.70 |
1.50 |
1.69 |
1.47 |
|
| April |
1.63 |
1.67 |
|||
| May |
1.24 |
1.75 |
1.65 |
||
| June |
2.43 |
1.79 |
|||
| July |
2.67 |
2.76 |
2.61 |
1.94 |
|
Graphical and statistical analysis of the proportion of time Dall’s sheep spent active, the feeding efficiency, and behavior of Dall’s sheep relative to overflights by small civilian single engine fixed wing aircraft.
Table E.1. Summary of ANCOVA results examining factors affecting the proportion of time Dall’s sheep were active including the relation to overflights by small civilian single engine aircraft during field sessions in 2000 and 2001. Two data sets were considered. One model was examined without considering the presence of lambs, and a second model (restricted to May, June and July) included lambs in the analysis. Observations were made at 2 study sites in the Yukon-Tanana Uplands of Interior Alaska.| Dependent variable |
Independent Variable* |
d.f. |
F |
P |
Partial eta squared |
| Proportion Active (ewe/overflight model) |
|||||
| Rock |
1 |
3.539 |
0.062 |
0.022 |
|
| Ewe |
1 |
0.161 |
0.689 a |
0.001 |
|
| Overflight |
2 |
0.308 |
0.735 |
0.004 |
|
| Site |
1 |
4.544 |
0.035 |
0.027 |
|
| Year(site) |
2 |
3.290 |
0.040 |
0.039 |
|
| Sequence(year(site)) |
12 |
2.897 |
0.001 |
0.178 |
|
| Proportion Active (lamb/overflight model) |
|||||
| Rock |
1 |
0.118 |
0.732 |
0.001 |
|
| Ewe |
1 |
0.212 |
0.646 |
0.002 |
|
| Lamb |
1 |
1.019 |
0.315 |
0.011 |
|
| Overflight |
2 |
0.466 |
0.629 |
0.010 |
|
| Site |
1 |
0.020 |
0.888 a |
0.000 |
|
| Year(site) |
1 |
0.181 |
0.672 |
0.002 |
|
| Sequence(year(site)) |
5 |
0.521 |
0.759 |
0.027 |
* Independent variables used in model were: 1) distance from steep rocks; 2) number of ewes in group; 3) number of lambs in group; 4) before, during, or after small single engine aircraft overflight event; 5) study site; 6) year nested within study site; and 7) date sequence nested within year nested within study site
a Interactions between independent variables were assumed if the significance (P<0.05) of an independent variable differed when comparing Type III and Type I sum of squares.
 |
| Figure E.1. Mean (+SE) proportion of Dall’s sheep active during scan sampling in: 1) the 10 minutes before a small single engine aircraft overflight event (n=50 for ewe model and n=29 for lamb model); 2) during a small single engine aircraft overflight event (n=75 for ewe model and n=44 for lamb model); and 3) 10 minutes after the overflight event (n=56 for ewe model and n=33 for lamb model). Observations were made at 2 study sites in the Yukon-Tanana Uplands of Interior Alaska. Observations were made between late February and early August for the ewe/model and a subset of this data (observations between May and August) was used for the lamb/model. |
Table E.2. Summary of ANCOVA results examining factors affecting the feeding efficiency of Dall’s sheep including the relation to overflights by small civilian single engine aircraft during field sessions in 2000 and 2001. Two data sets were considered. One model was examined without considering the presence of lambs, and a second model (restricted to May, June and July) included lambs in the analysis. Observations were made at 2 study sites in the Yukon-Tanana Uplands of Interior Alaska.
| Dependent variable |
Independent variable* |
d.f. |
F |
P |
Partial eta squared |
| Feeding Efficiency (ewe/overflight model) |
|||||
| Rock |
1 |
0.115 |
0.736 |
0.001 |
|
| Ewe |
1 |
0.782 |
0.379 |
0.007 |
|
| Overflight |
2 |
5.795 |
0.004 |
0.097 |
|
| Site |
1 |
0.115 |
0.735 |
0.001 |
|
| Year(site) |
2 |
1.624 |
0.202 |
0.029 |
|
| Sequence(year(site)) |
11 |
1.089 |
0.377 |
0.100 |
|
| Feeding Efficiency (lamb/overflight model) |
|||||
| Rock |
1 |
0.062 |
0.804 |
0.001 |
|
| Ewe |
1 |
0.381 |
0.539 |
0.006 |
|
| Lamb |
1 |
3.801 |
0.055 |
0.053 |
|
| Overflight |
2 |
1.939 |
0.152 |
0.054 |
|
| Site |
1 |
0.000 |
.991 |
0.000 |
|
| Year(site) |
1 |
0.029 |
0.865 |
0.000 |
|
| Sequence(year(site)) |
5 |
1.450 |
0.218 |
0.096 |
* Independent variables used in model were: 1) distance from steep rocks; 2) number of ewes in group; 3) number of lambs in group; 4) before, during, or after an overflight event; 5) study site; 6) year nested within study site; and 7) date sequence nested within year nested within study site
a Interactions between independent variables were assumed if the significance (P<0.05) of an independent variable differed when comparing Type III and Type I sum of squares.
 |
| Figure E.2. Mean (+SE) feeding efficiency of Dall’s sheep during scan sampling in: 1) the 10 minutes before a small single engine aircraft overflight event (n=37 for ewe model and n=22 for lamb model); 2) during a small single engine aircraft overflight event (n=50 for ewe model and n=34 for lamb model); and 3) 10 minutes after the overflight event (n=40 for ewe model and n=25 for lamb model). Observations were made at 2 study sites in the Yukon-Tanana Uplands of Interior Alaska. Observations were made between late February and early August for the ewe/model and a subset of this data (observations between May and August) was used for the lamb/model. |
Table E.3. Summary of MANCOVA results examining factors affecting the behavior of Dall’s sheep (percent bedding, standing, feeding, walking, and running) including the relation to overflights by small civilian single engine aircraft during field sessions in 2000 and 2001. Two data sets were considered. One model was examined without considering the presence of lambs, and a second model (restricted to May, June and July) included lambs in the analysis. Observations were made at 2 study sites in the Yukon-Tanana Uplands of Interior Alaska.
| Dependent Variable |
Independent Variable* |
d.f. |
F |
P |
Partial eta squared |
| Behavior |
|||||
| ewe/overflight model |
Rock |
4 |
1.085 |
0.366 |
0.027 |
| Ewe |
4 |
0.223 |
0.925 a |
0.006 |
|
| Overflight |
8 |
2.187 |
0.028 |
0.052 |
|
| Site |
4 |
1.345 |
0.256 |
0.033 |
|
| Year(site) |
8 |
1.910 |
0.058 a |
0.046 |
|
| Sequence(year(site)) |
48 |
2.247 |
0.000 |
0.145 |
|
| Behavior (lamb/overflight model) |
|||||
| Rock |
4 |
0.152 |
0.962 |
0.007 |
|
| Ewe |
4 |
0.390 |
0.815 |
0.017 |
|
| Lamb |
4 |
1.490 |
0.212 |
0.062 |
|
| Overflight |
8 |
1.732 |
0.094 |
0.071 |
|
| Site |
4 |
0.033 |
0.998 a |
0.001 |
|
| Year(site) |
4 |
0.218 |
0.928 a |
0.010 |
|
| Sequence(year(site)) |
20 |
1.738 |
0.027 |
0.087 |
* Independent variables used in model were: 1) distance from steep rocks; 2) number of ewes in group; 3) number of lambs in group; 4) before, during, or after a small single engine aircraft overflight event; 5) study site; 6) year nested within study site; and 7) date sequence nested within year nested within study site
a Interactions between independent variables were assumed if the significance (P<0.05) of an independent variable differed when comparing Type III and Type I sum of squares.
 |
| Figure E.3. Mean (+SE) behavior of Dall’s sheep during scan sampling in: 1) the 10 minutes before a small single engine aircraft overflight event (n=50 for ewe model and n=29 for lamb model); 2) during a small single engine aircraft overflight event (n=75 for ewe model and n=44 for lamb model); and 3) 10 minutes after the overflight event (n=56 for ewe model and n=33 for lamb model). Observations were made at 2 study sites in the Yukon-Tanana Uplands of Interior Alaska. Observations were made between late February and early August for the ewe/model and a subset of this data (observations between May and August) was used for the lamb/model. |
| Dependent variable |
Independent Variable* |
d.f. |
F |
P |
Partial eta squared |
| Proportion Active (ewe/sound model) |
|||||
| Rock |
1 |
6.986 |
0.014 |
0.212 |
|
| Ewe |
1 |
12.477 |
0.002 a |
0.324 |
|
| Proximity |
2 |
0.367 |
0.697 a |
0.027 |
|
| Leq (dBA) |
1 |
3.437 |
0.075 a |
0.117 |
|
| Site |
1 |
7.077 |
0.013 a |
0.214 |
|
| Year(site) |
2 |
5.602 |
0.009 a |
0.301 |
|
| Sequence(year(site)) |
8 |
1.463 |
0.219 |
0.310 |
|
| Proportion Active (lamb/sound model) |
|||||
| Rock |
1 |
9.006 |
0.008 a |
0.360 |
|
| Ewe |
1 |
13.342 |
0.002 |
0.455 |
|
| Lamb |
1 |
0.720 |
0.409 |
0.043 |
|
| Proximity |
2 |
2.693 |
0.048 |
0.050 |
|
| Leq (dBA) |
1 |
3.976 |
0.063 |
0.199 |
|
| Site |
1 |
9.110 |
0.008 |
0.363 |
|
| Year(site) |
1 |
9.030 |
0.008 a |
0.361 |
|
| Sequence(year(site)) |
3 |
3.179 |
0.053 a |
0.373 |
* Independent variables used in model were: 1) distance from steep rocks; 2) number of ewes in group; 3) number of lambs in group; 4) proximity to sheep of overflight by small civilian single engine aircraft; 5) sound level (2 minute mean Leq [dBA]); 6) study site; 7) year nested within study site; and 8) year nested within study site nested within date sequence.
a Interactions between independent variables were assumed if the significance (P<0.05) of an independent variable differed when comparing Type III and Type I sum of squares.
 |
| Figure E.4. Mean (+SE) proportion of Dall’s sheep active during scan sampling during overflights by small civilian single engine aircraft grouped by proximity: 1) close = aircraft lower than 1,500 m AGL and within 1.6 km horizontal distance from sheep (n=15 for ewe model and n=7 for lamb model); 2) moderate = aircraft lower than 1,500 m AGL and between 1.6 and 3.2 km horizontal distance from sheep (n=15 for ewe model and n=8 for lamb model); 3) far = aircraft higher than 1,500 m AGL and greater than 3.2 km horizontal distance from sheep (n=44 for ewe model and n=28 for lamb model). Observations were made at 2 study sites in the Yukon-Tanana Uplands of Interior Alaska. Observations were made between late February and early August for the ewe/model and a subset of this data (observations between May and August) was used for the lamb/model. |
 |
| Figure E.5. Mean (+SE) proportion of Dall’s sheep active during scan sampling during overflights by small civilian single engine aircraft grouped by 2 minute mean Leq (dBA): 1) < 40 dBA (n=77 for ewe model and n=53 for lamb model); 2) 41 – 50 dBA (n=16 for ewe model and n=10 for lamb model); and 3) > 51 dBA (n=6 for ewe model and n=3 for lamb model). Observations were made at 2 study sites in the Yukon-Tanana Uplands of Interior Alaska. Observations were made between late February and early August for the ewe/model and a subset of this data (observations between May and August) was used for the lamb/model. |
Table E.5. Summary of ANCOVA results examining factors affecting the feeding efficiency of Dall’s sheep including proximity and sound level (2 min. mean Leq [dBA]) of overflights by small civilian single engine aircraft during field sessions in 2000 and 2001. Two data sets were considered. One model was examined without considering the presence of lambs, and a second model (restricted to May, June and July) included lambs in the analysis. Observations were made at 2 study sites in the Yukon-Tanana Uplands of Interior Alaska.
| Dependent variable |
Independent variable* |
d.f. |
F |
P |
Partial eta squared |
| Feeding Efficiency (ewe/sound model) |
|||||
| Rock |
1 |
0.019 |
0.893 |
0.002 |
|
| Ewe |
1 |
0.014 |
0.907 a |
0.001 |
|
| Proximity |
2 |
0.581 |
0.574 |
0.088 |
|
| Leq (dBA) |
1 |
0.947 |
0.350 |
0.073 |
|
| Site |
1 |
0.019 |
0.894 |
0.002 |
|
| Year(site) |
2 |
0.009 |
0.991 |
0.002 |
|
| Sequence(year(site)) |
6 |
1.248 |
0.349 |
0.384 |
|
| Feeding Efficiency (lamb/sound model) |
|||||
| Rock |
1 |
0.112 |
0.745 a |
0.011 |
|
| Ewe |
1 |
0.000 |
0.998 |
0.000 |
|
| Lamb |
1 |
1.667 |
0.226 a |
0.143 |
|
| Proximity |
1 |
1.000 |
0.395 |
0.024 |
|
| Leq (dBA) |
1 |
0.030 |
0.866 |
0.003 |
|
| Site |
1 |
0.112 |
0.744 |
0.011 |
|
| Year(site) |
1 |
0.113 |
0.743 a |
0.011 |
|
| Sequence(year(site)) |
2 |
0.693 |
0.522 |
0.122 |
* Independent variables used in model were: 1) distance from steep rocks; 2) number of ewes in group; 3) number of lambs in group; 4) proximity of overflight to sheep; 5) sound level (2 minute mean Leq [dBA]); 6) study site; 7) year nested within study site; and 8) year nested within study site nested within date sequence.
a Interactions between independent variables were assumed if the significance (P<0.05) of an independent variable differed when comparing Type III and Type I sum of squares.
 |
| Figure E.6. Mean (+SE) feeding efficiency of Dall’s sheep during scan sampling during overflights by small civilian single engine aircraft grouped by proximity: 1) close = aircraft lower than 1,500 m AGL and within 1.6 km horizontal distance from sheep (n=9 for ewe model and n=6 for lamb model); 2) moderate = aircraft lower than 1,500 m AGL and between 1.6 and 3.2 km horizontal distance from sheep (n=9 for ewe model and n=5 for lamb model); 3) far = aircraft higher than 1,500 m AGL and greater than 3.2 km horizontal distance from sheep (n=31 for ewe model and n=22 for lamb model). Observations were made at 2 study sites in the Yukon-Tanana Uplands of Interior Alaska. Observations were made between late February and early August for the ewe/model and a subset of this data (observations between May and August) was used for the lamb/model. |
 |
| Figure E.7. Mean (+SE) feeding efficiency of Dall’s sheep during scan sampling during overflights by small civilian single engine aircraft grouped by 2 minute mean Leq (dBA): 1) < 40 dBA (n=51 for ewe model and n=42 for lamb model); 2) 41 – 50 dBA (n=11 for ewe model and n=8 for lamb model); and 3) > 51 dBA (n=5 for ewe model and n=2 for lamb model). Observations were made at 2 study sites in the Yukon-Tanana Uplands of Interior Alaska. Observations were made between late February and early August for the ewe/model and a subset of this data (observations between May and August) was used for the lamb/model. |
Table E.6. Summary of MANCOVA results examining factors affecting the behavior of Dall’s sheep (percent bedding, standing, feeding, walking, and running) including proximity and sound level (2 min. mean Leq [dBA]) of overflights by small civilian single engine aircraft during field sessions in 2000 and 2001. Two data sets were considered. One model was examined without considering the presence of lambs, and a second model (restricted to May, June and July) included lambs in the analysis. Observations were made at 2 study sites in the Yukon-Tanana Uplands of Interior Alaska.
| Dependent Variable |
Independent Variable* |
d.f. |
F |
P |
Partial eta squared |
| Behavior (ewe/sound model) |
|||||
| Rock |
3 |
2.178 |
0.117 a |
0.214 |
|
| Ewe |
3 |
4.022 |
0.019 |
0.335 |
|
| Proximity |
6 |
0.526 |
0.786 |
0.062 |
|
| Leq (dBA) |
3 |
1.396 |
0.268 |
0.149 |
|
| Site |
3 |
2.206 |
0.113 a |
0.216 |
|
| Year(site) |
6 |
2.586 |
0.030 a |
0.244 |
|
| Sequence(year(site)) |
24 |
1.027 |
0.447 |
0.252 |
|
| Behavior (lamb/sound model) |
|||||
| Rock |
3 |
2.695 |
0.086 a |
0.366 |
|
| Ewe |
3 |
4.719 |
0.018 a |
0.503 |
|
| Lamb |
3 |
0.769 |
0.530 |
0.141 |
|
| Proximity |
6 |
1.325 |
0.279 |
0.221 |
|
| Leq (dBA) |
3 |
1.233 |
0.335 |
0.209 |
|
| Site |
3 |
2.733 |
0.083 a |
0.369 |
|
| Year(site) |
3 |
2.710 |
0.085 |
0.367 |
|
| Sequence(year(site)) |
9 |
1.360 |
0.244 |
0.220 |
* Independent variables used in model were: 1) distance from steep rocks; 2) number of ewes in group; 3) number of lambs in group; 4) proximity of overflight to sheep; 5) sound level (2 minute mean Leq [dBA]); 6) study site; 7) year nested within study site; and 8) year nested within study site nested within date sequence.
a Interactions between independent variables were assumed if the significance (P<0.05) of an independent variable differed when comparing Type III and Type I sum of squares.
 |
| Figure E.8. Mean (+SE) behavior of Dall’s sheep during scan sampling during overflights by small civilian single engine aircraft grouped by proximity: 1) close = aircraft lower than 1,500 m AGL and within 1.6 km horizontal distance from sheep (n=15 for ewe model and n=7 for lamb model); 2) moderate = aircraft lower than 1,500 m AGL and between 1.6 and 3.2 km horizontal distance from sheep (n=15 for ewe model and n=8 for lamb model); 3) far = aircraft higher than 1,500 m AGL and greater than 3.2 km horizontal distance from sheep (n=44 for ewe model and n=28 for lamb model). Observations were made at 2 study sites in the Yukon-Tanana Uplands of Interior Alaska. Observations were made between late February and early August for the ewe/model and a subset of this data (observations between May and August) was used for the lamb/model. |
 |
| Figure E.9. Mean (+SE) behavior of Dall’s sheep during scan sampling during overflights by small civilian single engine aircraft grouped by 2 minute mean Leq (dBA): 1) < 40 dBA (n=77 for ewe model and n=53 for lamb model); 2) 41 – 50 dBA (n=16 for ewe model and n=10 for lamb model); and 3) > 51 dBA (n=6 for ewe model and n=3 for lamb model). Observations were made at 2 study sites in the Yukon-Tanana Uplands of Interior Alaska. Observations were made between late February and early August for the ewe/model and a subset of this data (observations between May and August) was used for the lamb/model. |
Power Analysis for Usage Variables
Here a power analysis is conducted to determine an adequate sample size for detecting overflight effects in sheep home range size, average daily distance traveled, and vegetation type usage. Statistical power is the probability of detecting effects given they are present in the sampled population. If certain effects are present, they can always be detected with high probability by increasing the sample size of observed individuals. In some cases, however, the sample size often has to be increased to an unattainable size in order to detect small effects in the sampled population. Although no significant jet overflight effects were observed, the number of collared sheep is relatively low; this implies that sample size may be too low to have a high probability of detecting them. Therefore, a power analysis was performed to determine the number of sheep that would have to be collared to detect sortie effects at least as large as what was observed.
Three models used were examined for their ability to detect present sortie effects: the MANOVA model for determining sortie effects on vegetation type usage and the two ANOVA models for examining sortie effects on average daily distance traveled and home range size over each 2 week sequence. For the 2 ANOVA analyses, exact power calculations were made, however, due to the complexity of the MANOVA test statistic sampling distribution, simulations were necessary to approximate the power of the vegetation usage analysis.
In both of the ANOVA models the “effects” parameterization was used for the power analysis. For a simple 2 covariate model, the effects parameterization is given by
Yk = ai + bj + cij + ek,
where Yk is the response variable individual k = 1,…, n. The parameters ai and bj represent “main effects” and cij represents an “interaction effect” for i = 1,…, I and j = 1,…, J, and ek represents an error term for individual k, usually normally distributed.
Parameters are usually estimated using the least squares matrix equation
B = (X’X)-1X’Y,
where B is the vector of parameters, X is the design matrix filled with indicator vectors for each effect parameter (see Neter et al. 1996, chapter 11) and Y is the vector of individual observations. The model statement, the usual type of hypothesis test is of the form
H0: b1 = b2 = … = bJ = 0;
that is to say, the second covariate has no effect on the response variable. The test statistic used to test this type of hypothesis is the F statistic given by
,
where SSE is the error sum of squares. The subscripts f and r refer to the SSE values when the full model is used and when the reduced model (without the covariate being tested) is used. The df values are degrees of freedom. Both df1 and df2 are calculated based the ranks of the matrices used to calculate the numerator and denominator of the F ratio (see Hocking 1996).
The F ratio has a central F-distribution with df1 and df2 degrees of freedom if the null hypothesis is true; all of the tested parameters are in fact equal to 0 in reality. Therefore, the null hypothesis is rejected if the calculated F ratio exceeds the 95th percentile of the central F-distribution. This gives a Type I error rate of 5%. If the null hypothesis is in fact false, however, the F ratio has a “non-central” F-distribution with non-centrality parameter l. Hocking (1996) provides a formulation for l. Under the assumption of normal errors, the power of the test, which is equal to the probability that one rejects the null hypothesis when it is false, is equal to
Pr{F > F(0.95, df1, df2)},
where the random variable F has a non-central F-distribution with df1 and df2 degrees of freedom and F(0.95, df1, df2) is the 95th percentile of the corresponding central distribution. This can be calculated directly from the cumulative distribution function of the non-central F-distribution.
The ANOVA models used for the analysis of average daily movement and home range size represent an incomplete design when all 2-way interactions of the covariates, study area, year, and sequence, are included. This is due to the fact that not all sequences we’re observed in every year. The implication of this is that the parameters estimated with the least squares equation are not unique as the inverse of the X’X matrix does not exist. Therefore, the effects parameters do not have a well defined interpretation. So, only sample size adjustments were examined for their effect on power to detect sortie effects.
To examine the sample size effects on the power to detect sortie effects sample size was iteratively increased and the power was calculated. Power calculations were made by assuming the estimated cell means from the least squares predictions were the true population means. Sample sized was then increased by the addition of 1 observation to each year*sequence that was observed in the study. This would result from the addition of 2 collared sheep per year, one in each study area. Sample size was increased in this manner in order to keep the dimension of the model parameters the same. If observations were added to year*sequence cells where no observations were made adds additional model degrees of freedom. Since absence of observations in a certain cell is due to inability to make the observations at that time we felt that it was unrealistic to add observations where they could not have been made.
Figure 1 illustrates the power curves for average daily distance and home range size analyses, as well as the MANOVA vegetation type use analysis discussed later. The curves show that the addition of 10 observations for each year*sequence observed in the study (indicated with the vertical line) will result in a power of approximately 0.82 for detecting the sortie effect on average daily distance traveled and 0.77 for detecting sortie effects on home range size. This indicates that it is probably necessary to double the number of collared sheep to detect sortie effect as large as what was estimated with the given sample.
The same procedure was followed for the power analysis of the MANOVA model used to investigate sortie effects on the vector of vegetation type usage. Parameters are estimated with the same least squares equation, but, now the set of parameters B is a matrix. A common test statistic is based on the likelihood ratio
L = |E| / |H+E|,
where | ∙ | represents the determinant of a matrix, E is the sum of squared error matrix for the full model, H is the difference is error sums of squares between the reduced model and the full model. An F statistic is then calculated from this ratio (see Johnson and Wichern 1992, Chapter 7 for complete description of the F statistic and associated degrees of freedom df1 and df2). Unfortunately, under the alternative hypothesis the non-centrality parameter is difficult to calculate. Therefore, a simulation is used to approximate the power calculation stochastically. For each step in the addition of observations described previously, a simulation was performed to determine Pr{F > F(0.95, df1, df2)}.
When sample size was increased the predicted values were calculated based on the estimated values from the full model calculated with the real data. These parameter values were taken for “reality” as with the ANOVA models. For each predicted value a multivariate normal error term was simulated with the variance-covariance matrix calculated from the real data. This was repeated 1000 times and the proportion of times that the sortie effects were significant were used to approximate the power for the given sample size. Again, Figure 1 illustrates the power for the multivariate test for sortie effects on the vector of vegetation type usage. With the addition of 10 observations per year*sequence, the power for detecting sortie effects is approximately 0.78.
Overall, it appears that in order to have a reasonable chance of detecting sortie effects given they are at least as large as what was observed with the current sample, the number of collared sheep should be doubled at minimum. Therefore, the lack of significant sortie effects in the present analysis should not be taken for absence of any sortie effects. The current sample size is not large enough to detect significant sortie effects that are as large as the estimated effects.
 |
Figure F.1. Power curves for detecting sortie effects. Average daily distance traveled and home range size power curves were calculated exactly. Power for sortie effects on vegetation type usage was simulated. The vertical line represents a sample size twice as large as the current data set. |
2004 Sheep Report
http://www.nps.gov/yuch/Expanded/key_resources/sheep/sheep_2004.htm
Doug Beckstead
December 8, 2004
