Big Game Statistics: Bighorn Sheep
BIGHORN SHEEP: Table of Contents
Overview
Life history ........................................................................................................ 119
Habitat and habitat management options ..........................................................119
Distribution ...................................................................................................... 120
Inventory ...........................................................................................................121
2004 Statistical Reports
Bighorn sheep herd composition, fall and spring ............................................... 122
Bighorn sheep season harvest ............................................................................124
118
Oregon Department of Fish and Wildlife
Overview
Historically, 2 subspecies of bighorn sheep (Ovis canadensis) were native to Oregon. The
Rocky Mountain subspecies (O. c. canadensis) inhabited the northeastern corner of the
state from the John Day-Burnt River divide, north and east to the Snake River and the
Oregon-Washington state line. The California subspecies (O. c. californiana) ranged over
southeast and southcentral Oregon and through much of the John Day and Deschutes
River drainages.
Settlement of the west brought with it overhunting, changes in land use, domestic
livestock, and associated diseases which negatively impacted native bighorn populations. Bighorn were gone from Oregon by 1945. Their re-establishment has been very
successful, but not without setbacks, particularly from disease outbreaks.
Life History
Bighorn sheep are gregarious and spend most of the year in group associations of one
form or another. Except for the breeding season, ram groups generally live separately
from ewe-lamb-subadult groups. These ram groups, often called “bachelor groups,”
frequently occupy habitats not used by the ewes and lambs, which reduces competition
for available resources. Ram groups maintain a social hierarchy that is established and
maintained primarily through head butting rituals. This behavior establishes dominance
within the ram segment of the population and results in larger, more dominant rams
doing most of the breeding.
Bighorn Sheep
Big Game Statistics: Bighorn Sheep
Oregon Department
of Fish and Wildlife
3406 Cherry Ave NE
Salem, OR 97303
www.dfw.state.or.us
There is little interaction between the sexes until fall, when the groups combine for
the breeding season or rut. In Oregon, the rut usually begins in October, peaks during
November, and ends by early December.
Habitat & Habitat Management Options
In general, bighorn sheep prefer rugged, open habitat that provides high visibility of
their surroundings. Cliffs, rimrock, and rocky outcrops are important habitat components for bighorn sheep survival. These habitats are particularly important for lambing
and escape from predators. Bighorn sheep do not normally use tree cover to the extent
that deer or elk do, but it is not unusual to find them seeking shade under conifers,
juniper, or mountain mahogany where available.
Oregon Department of Fish and Wildlife
119
Big Game Statistics: Bighorn Sheep
Grasses are a staple in the bighorn’s diet through
most of the year. Forbs and shrubs are of seasonal
importance depending on type and availability. Within
certain plant community types, fire can be used to remove the dead, unpalatable remains of forage plants
and renew their growth and vigor, thereby improving
forage quantity and quality.
On historic ranges where the condition of plant communities is poor, spraying of undesirable plant species
and/or fertilization can be used to improve the forage
resource for bighorn sheep.
Water is an essential requirement of bighorn sheep
and in some cases may limit their distribution, especially in southeastern Oregon. Habitat improvements
such as spring developments or guzzler installations
have made historic habitat once again suitable for
bighorn sheep.
Distribution
Overall, most established herds are stable to increasing, although it will take a few years to evaluate the
success of recent transplants. The annual rate of
increase in all populations tends to decrease as total
population size increases. The exact cause for this
drop in productivity or survival is not yet known.
Management
California Bighorn Transplant History
During November 1954, 20 bighorn sheep were
trapped near Williams Lake, British Columbia, and
released in a 1,000-acre holding pasture on the west
face of Hart Mountain. This population thrived and
has been the source of most California bighorn transplants in Oregon since 1960.
Through February 2003, more than 3,091 California
bighorn have been trapped in southeast Oregon and
transplanted to about 30 sites in Oregon. Bighorn
sheep have also been provided to Nevada, Washington, Idaho, Wyoming and North Dakota. Most of
these animals are descendants of the original Williams
Lake sheep. In February 2000 16 animals of Penticton,
120
British Columbia origin, were moved from Nevada to
Steens Mountain to evaluate the effects of genetics in
California bighorn sheep.
Natural range expansion from a population in Idaho
has resulted in establishment of an additional California bighorn herd in the upper Owyhee River drainage
near the Idaho border in Malheur County.
Transplants of bighorn sheep usually are composed
primarily of females, lambs, and young rams. The
desired ram to ewe ratio for a transplant is one ram
for every three to four ewes. The Department does
not attempt to transplant large rams because they are
difficult to handle in the capture process and tend to
wander from the release site once released. Continued trapping and transplanting over time will leave a
population with more adult males than females. As a
result, there will be more rams in the population than
needed for breeding. Therefore, hunting of rams is
used to keep the ram to ewe ratio at desired levels.
Oregon’s bighorn sheep seasons are designed to provide a quality hunting experience with a reasonable
chance of success. The number of tags authorized
each year are based on total population size, proportion of rams in the population, and the availability of
mature rams, size of the herd range (hunt area), and
previous lamb recruitment rates. Some bighorn sheep
herd ranges are relatively small, and hunter crowding
could occur if too many permits were authorized for
a specific period. Therefore, two or more consecutive
hunts have been authorized in some herd ranges.
Past harvest has rarely exceeded 15 percent of total
estimated ram populations and less than five percent
of the total population.
Rocky Mountain Bighorn Transplant History
From 1971 to 2003, 29 transplants totaling 444
sheep were made to 19 Oregon locations. Transplants
varied from 2 to 30 animals in 12 separate herds.
In addition, Rocky Mountain bighorns were sent to
Idaho and Washington.
Oregon Department of Fish and Wildlife
Big Game Statistics: Bighorn Sheep
Inventory
Bighorns are generally surveyed 1 to 2 times per
year by helicopter or from the ground in late fall and
spring. They are classified as ewes, lambs and rams.
Rams are further classified by age class as ¼, ½, ¾
and full curl.
Oregon Department of Fish and Wildlife
121
122
WATERSHED
Oregon Department of Fish and Wildlife
CALIFORNIA BIGHORN TOTAL
ALDRICH MOUNTAIN
JOHNDAY
McCLELLAN MOUNTAIN
JOHNDAY
BURNT RIVER
GRANDE RONDE
LOWER JOHN DAY RIVER (E JOHNDAY
POTAMUS
JOHNDAY
LOWER JOHN DAY RIVER (WDESCHUTES
LOWER DESCHUTES (E)
DESCHUTES
LOWER DESCHUTES (W)
DESCHUTES
STEEN'S MOUNTAIN
MALHEUR
BLK PNT / ALVORD PEAKS MALHEUR
S. CATLOW RIM
MALHEUR
PUEBLO MOUNTAINS
MALHEUR
MICKEY BUTTE
MALHEUR
HEATH RIM
MALHEUR
PALAMINO CANYON
MALHEUR
SQUAW CREEK
MALHEUR
RIVERSIDE
MALHEUR
ANDREWS RIM
MALHEUR
N. CATLOW RIM
MALHEUR
LONE MOUNTAIN
MALHEUR
STONEHOUSE CANYON
MALHEUR
WILDCAT CREEK
MALHEUR
HART MOUNTAIN
KLAMATH
ABERT RIM
KLAMATH
HADLEY BUTTE
KLAMATH
DIABLO / SHEEP ROCK
KLAMATH
COGLAN HILLS
KLAMATH
FISH CREEK RIM
KLAMATH
MILL CREEK
KLAMATH
COLEMAN RIM
KLAMATH
ALKALI RIM
KLAMATH
DAUGHTERY RIM
KLAMATH
WINTER RIDGE
KLAMATH
UPPER OWYHEE CANYON MALHEUR
MIDDLE OWYHEE CANYON MALHEUR
LOWER OWYHEE CANYON MALHEUR
E. TROUT CR. MTN
MALHEUR
RATTLESNAKE CREEK
MALHEUR
TENMILE CREEK
MALHEUR
SOUTH PAULINA
DESCHUTES
CALIFORNIA BIGHORN
AREA
10
14
31
155
17
26
62
29
60
51
34
63
22
4
13
5
30
7
63
11
10
3
75
11
7
59
32
14
-9
-17
3
48
-93
34
68
7
19
864 1216
32
20
29
70
3
24
42
25
61
23
10
35
25
3
2
4
27
6
27
3
8
11
64
42
0
30
20
8
-7
-10
2
55
-66
31
24
9
6
405
7
12
6
41
8
11
22
16
14
18
3
20
8
2
3
0
3
1
11
2
5
1
35
10
1
12
13
11
-6
-2
0
15
-35
6
42
2
1
2485
49
46
66
266
28
61
126
70
135
92
47
118
55
9
18
9
60
14
101
16
23
15
174
63
8
101
65
33
-22
-29
5
118
-194
71
134
18
26
BIGHORNS CLASSIFIED
RAMS EWES LAMBS TOTAL
71
320
143
94
45
18
92
68
86
102
45
29
56
114
75
15
80
90
86
43
27
80
367
85
382
0
51
63
57
-78
-59
67
115
-71
91
35
129
32
61
193
325
93
-74
74
68
46
32
12
16
123
31
48
--48
-42
-9
-89
-29
104
95
218
-220
-100
67
37
41
-10
8
-33
68
41
103
64
68
-63
100
84
56
130
25
-31
--100
3
-49
-16
108
59
-400
138
--------------66
288
480
75
51
-84
85
52
63
-6
21
------120
---57
-100
43
93
77
-------33
---20
48
288
480
135
27
-65
104
67
63
74
36
118
31
--113
74
100
65
-25
54
77
70
100
172
129
21
--5
-33
15
133
42
37
63
150
65
RAMS PER 100 EWES
2004 2003 2002 2001 2000
33
70
86
19
26
47
42
35
55
23
35
9
32
36
50
23
0
10
14
17
18
50
33
47
91
14
20
41
79
-67
-12
0
31
-38
18
62
29
5
33
29
88
50
-56
56
45
66
31
28
34
38
43
18
--18
-28
-27
-35
--36
16
35
-140
-33
33
23
41
-19
23
-10
39
30
34
50
35
-59
45
65
21
10
16
----14
52
-17
-47
62
45
-300
25
--------------38
50
70
41
43
-45
23
46
40
-31
57
------20
---61
-18
26
44
40
-------21
---30
40
50
70
45
54
-73
42
57
17
12
7
53
38
--25
65
100
47
-13
23
55
16
28
24
33
50
--53
-67
27
67
33
30
19
38
6
LAMBS PER 100 EWES
2004 2003 2002 2001 2000
BIGHORN SHEEP HERD COMPOSITION, FALL AND SPRING 2003 - 2004
90
120
75
-28
80
160
100
--------------300
180
25
205
150
120
-60
-60
8
------30
90
120
80
310
-80
100
115
195
70
60
-60
--40
95
40
160
-40
45
300
---------5
-------2971 2005
90
120
80
-100
100
135
100
195
95
100
150
140
100
40
40
100
40
160
-40
-300
-50
140
100
120
-60
-60
6
100
80
-120
100
10
40
1978
1988
1987*
1989 & 1990
2003
1995
1993
1995
1961
EXPANSION
1989
1983
1991
1990
2002
1993
1988
EXPANSION
1989
1992
1996
1996
1954
1977
1984
1991
1989
1988
1995
1991
No transplant
1994
1992
1983
1983
1965
1987
1992
1993
1995
INITIAL
POPULATION EST.
DATE OF
2004 2003 2002 TRANSPLANT
Big Game Statistics: Bighorn Sheep
Oregon Department of Fish and Wildlife
GRANDE RONDE
GRANDE RONDE
GRANDE RONDE
GRANDE RONDE
GRANDE RONDE
GRANDE RONDE
GRANDE RONDE
GRANDE RONDE
GRANDE RONDE
GRANDE RONDE
GRANDE RONDE
GRANDE RONDE
GRANDE RONDE
GRANDE RONDE
GRANDE RONDE
DISTRICT
* Includes 9 sheep transplanted 01-31-97
** Lost Prairie merged with Wenaha
GRAND TOTAL
ROCKY MOUNTAIN BIGHORN TOTAL
LOSTINE
LOWER IMNAHA
BEAR / MINAM
WENAHA
UPPER JOSEPH CREEK
UPPER HELLS CANYON
LOST PRAIRIE **
LOWER HELLS CANYON
MUIR CREEK
SLUICE / SADDLE
LEAP CREEK
BIG SHEEP
MINAM
FOX CREEK
SHEEP MOUNTAIN
ROCKY MOUNTAIN BIGHORN
AREA
1030 1525
309
17
19
9
---39
20
10
5
1
---29
7
166
44
81
12
32
18
18
24
44
9
21
7
9
500
95
5
2
2
---13
1
4
34
3
17
7
7
3055
570
72
159
24
70
32
34
-32
26
12
---81
28
BIGHORNS CLASSIFIED
RAMS EWES LAMBS TOTAL
68
54
55
54
75
66
39
50
-59
26
11
---74
35
59
55
51
38
120
62
37
80
-27
40
14
---103
42
64
55
57
50
77
54
47
82
-5
59
----72
58
62
51
45
36
100
50
42
87
-43
36
0
0
--68
74
48
53
54
69
25
47
25
75
50
13
--17
30
25
135
60
RAMS PER 100 EWES
2004 2003 2002 2001 2000
33
31
9
42
25
53
39
39
-29
11
22
---33
5
35
39
36
60
40
41
58
13
-47
13
0
---39
--
37
32
55
35
46
17
35
14
-45
35
----28
0
38
37
50
42
50
29
32
13
-64
79
75
0
--29
0
41
45 *
27
33
33
19
50
38
57
73
--0
40
38
24
18
LAMBS PER 100 EWES
2004 2003 2002 2001 2000
BIGHORN SHEEP HERD COMPOSITION, FALL AND SPRING 2003 - 2004
625
80
165
35
65
40
45
-35
25
10
---90
35
581
75
150
35
65
35
50
-35
35
----67
34
660 3596 2586
660
80
175
35
80
40
45
-40
30
15
---90
30
1999
2000
2000
1993
1990
1971
1979
1985
1984
EXPANSION
1979
EXPANSION
EXPANSION
1997
INITIAL
POPULATION EST.
DATE OF
2004 2003 2002 TRANSPLANT
Big Game Statistics: Bighorn Sheep
123
Big Game Statistics: Bighorn Sheep
2003 BIGHORN SHEEP SEASON HARVEST
HUNT #
543A1
543A2
543B1
543B2
543C
546A
546B1
546B2
551A
566A1
566A2
567A1
567A2
567B
568A1
568A2
568B
568C1
568C2
568D1
568D2
569A1
569A2
569B1
569B2
570A1
570A2
570A3
570B1
570B2
571A1
571A2
571A3
574
575A
CALIFORNIA BIGHORN HUNTS
# OF
RAMS
HUNT NAME
HUNTERS TAKEN
E. John Day River
W. John Day River
E. Deschutes River #1
E. Deschutes River #2
W. Deschutes River
Aldrich
McClellan #1
McClellan #2
Burnt River Canyon
Riverside #1
Riverside #2
East Owyheee #1
East Owyhee #2
West Owyhee
Upper Owyhee #1
Upper Owyhee #2
East Trout Creek Mts
Alvord-Buckskin #1
Alvord-Buckskin #2
Sheepshead Mts #1
Sheepshead Mts #2
Steens Mt #1
Steens Mt #2
North Catlow Rim #1
North Catlow Rim #2
Hart Mt #1
Hart Mt #2
Hart Mt #3
East Beatys Butte #1
East Beatys Butte #2
Poker Jim #1
Poker Jim #2
Poker Jim #3
Warner Unit
S. Central
3
3
2
2
1
2
2
1
1
1
1
1
1
1
1
2
2
2
1
1
1
2
2
1
1
1
1
2
3
3
1
1
1
4
4
3
3
2
2
1
2
2
1
1
1
1
1
1
1
1
2
2
2
1
1
1
2
2
1
1
1
1
1
3
3
1
0
1
4
4
Total California Bighorn
59
57
Hunter Success Rate
97 Percent
ROCKY MOUNTAIN BIGHORN HUNTS
# OF
RAMS
HUNT #
HUNT NAME
HUNTERS TAKEN
Chesnimnus
Snake River #1
Snake River #2
Hurricane Divide
Bear Creek
Sheep Mountain
Lookouit Mt
1
3
2
2
1
1
2
1
3
2
2
1
0
2
Total Rocky Mountain Bighorn
12
11
558A
559A1
559A2
560A
560B
562A
564
Hunter Success Rate
Auction Tag, W. John Day R.
Tag Sold For: $78,000
1
1
Raffle Tag, E. John Day R.
Total Ticket Sales: $40,300
1
1
GRAND TOTALS: Hunters = 73, Sheep Taken = 70, with 96% Success
NOTE: According to Oregon Revised Statutes, no less than 5% and no more than 10% of Bighorn
Sheep tags will be issued to non-residents. In 2003, 4 non-resident tags were issued; two
in Hart Mountain #3, one in Poker Jim #2, and one in Snake River #2.
124
92 Percent
Oregon Department of Fish and Wildlife
Big Game Statistics: Rocky Mountain Goats
Oregon Department of Fish and Wildlife
125