The food habits and summer distribution of juvenile sage grouse in central Montana
by Joel Gordon Peterson
A thesis submitted to the Graduate Faculty in partial fulfillment of the requirements for the degree of
MASTER OF SCIENCE in Fish and Wildlife Management
Montana State University
© Copyright by Joel Gordon Peterson (1969)
Abstract:
The food habits of juvenile sage grouse (Centrocercus urophasianus) were studied in central Montana
during the summers' of 1966 and 1968. The vegetation was analyzed at all feeding sites where birds
were collected= A measure of preference was established for each plant by correlating the percent
volume found in the crops with the percent canopy coverage found at the feeding sites. For the two
years combined, forbs averaged 75 percent of the diet of 127 juveniles through 12 weeks of age. Use of
forbs was greater in 1968, apparently due to the above average precipitation and the resulting greater
forb cover. The flower buds and leaves of common dandelion (Taraxacum officinale) and common
salsify (Tragapo-gon dubius) were the most highly preferred and utilized forbs, comprising 25 and 15
percent of the diets, respectively= Other forbs commonly utilized by various ages of juveniles were
prairie pepperweed (Lepidium densiflorum), prickly lettuce (Lactuca serriola), alfalfa (Medicago
sativa), curlcup gumweed (Grindelia squarrosa), and fringed sagewort (Artemisia frigida). Big
sagebrush (Artemisia tridentata) received little use until the birds were 11 weeks old. Insect use
declined steadily from a high of 60 percent of the diet in one-week chicks to 5 percent in 12-week-old
juveniles. The vegetational and topographical characteristics of brood sites found along two
observation routes were recorded during each week of the study. After the first few weeks of age,
observed brood locations were less frequent on the sagebrush-grass land benches and more frequent on
lower areas until by September, the majority of broods were located on bottomlands. Sagebrush heights
of 6 to 18 inches were the most prevalent heights at brood sites during their morning and evening
activity periods. Important components of juvenile sage grouse habitat in this area appears to be an
abundance and diversity of forbs and scattered (1-5 percent) or common (5-20 percent) densities of
sagebrush. >
.
THE FOOD HABITS AND SUMMER DISTRIBUTION OF JUVENILE SAGE GROUSE
. IN C E N T R A L M O N T A N A
by
JOEL GORDON PETERSON
A t h e s i s s u b m i t t e d t o t h e G r a d u a t e F a c u l t y in p a r t i a l
fulfillment of the requirements for the degree
of
MASTER OF SCIENCE
in
Fish and Wildlife Management
Approved:
a j o r Dep/arftment
Chairiiian 3 E x a m i ni n g /Cbrnrni t t e e
Graduate Dean
MONTANA STATE UNIVERSITY
Bozeman, Montana
■ J u n e , 1969
iii
ACKNOWLEDGEMENT
To the following, among others, I wish to extend sincere appreci­
ation for their contributions to this study:
Dr. Robert L. Eng, Mon­
tana State University, for technical supervision and guidance in
preparation of the manuscript; Dr. Richard J. Mackie, formerly with
the Montana Department of Fish and Gamei for initial project planning;
Mr. Duane Pyrah, Montana Department of Fish and Game for advice and
field assistance; Mr. Kenneth Greer, Montana Department of Fish and.
Game, for advice and assistance in analysis of grouse stomach contents;
Dr. W. E. Booth, Montana State University, for verification of plant
specimens; Mr. Thomas Mussehl, Montana Department of Fish and Game,
for assistance and advice; Dr. Don C. Quimby and Dr. Richard J. Graham,
Montana State University, for critical reading of the manuscript; the
other graduate students who worked on the project; and to my wife, Sheila,
for encouragement and assistance.
During this study, I was supported by
the Montana Fish and Game Department under Federal Aid Project Nos.
W-105-R-1, W-105-R-2, W-IOS-R-Si and W-105-R-4 and the United States
Department of the Interior, Bureau of Land Management.
J-V .
■ TABLE OF CONTENTS
Page
V I T A . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. ..
ACKNOWLEDGEMENT.
ii
. . . . . . -. . . . . . ..
m
T A B L E O F C O N T E N T S . . . . . . . . . . . ■. . . . . . . . . . . . . . . . . . . . . . .
L I S T O F T A B L E S . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
L I S T 'OF F I G U R E S . . . . . . . . . .
. iv
v
vi
A B S T R A C T ... .. . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . ■ v i i
I N T R O D U C T I O N . .. . . . . . .
I
DESCRIPTION OF AREA...;,....
2
:
M
E
T
H
O
D
S
.. . . . . . . . . . . . 4
R E S U L T S .. . . . . . . . . . . . . . . . . . . . . . ■. . . . . . . . . . . . . . . . . . . . . . . .
F o o d H a b i t s . . . . - ... . . . . . . . . . . . . . . . . .
B r o o d D i s t r i b u t i o n ! ... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
D I S C U S S I O N .... ......
9
9
18
24
A P P E N D I X . . . . -. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
LITERATURE CITE D;..................................-...........!38
V
Table
I.
LIST OF TABLES
Page
H
H
SOURCE AND AGE DISTRIBUTION OF 127 JUVENILE SAGE
GROUSE, AGES I THROUGH 12 WEEKS, 1966 AND 1968.. ..... .......
9
PERCENT FREQUENCY AND VOLUME OF FOOD ITEMS COMMONLY
UTILIZED BY I- THROUGH 12-WEEK-OLD SAGE GROUSE
COLLECTED DURING 1966 AND 1968. ...........................
IO
PERCENT VOLUME AND FREQUENCY OF COMMON PLANT AND
ANIMAL FOOD ITEMS FOUND IN SAGE GROUSE JUVENILES
13 WEEKS AND OLDER AkD ADULTS IN 1966 AND 1968........... 29
DIFFERENCES IN AMOUNT OF COMMON FOOD ITEMS FOUND IN
THE DIETS OF JUVENILE SAGE GROUSE BETWEEN 1966 AND 1968.. 14
V.
VEGETATIVE COMPOSITION FOUND AT 81 JUVENILE SAGE
GROUSE COLLECTION SITES, WITH EMPHASIS ON THE MORE
COMMONLY OCCURRING PLANT SPECIES............................. 30
M
PREFERENCE INDICES ASSIGNED TO PLANT FOOD ITEMS
FOUND IN THE CROPS AND AT THE FEEDING SITES OF 81
JUVENILE SAGE GROUSE COLLECTED DURING THE SUMMERS
O F 19 6 6
19 68 e c o e » f f l O O e e o o e e o e e o e e e o e o ‘e o e e e e e » * » e e e e e # »
H
<
in..
>
VII.
VIII.
IX.
X.
XI.
XII.
13
THE FIVE MOST PREFERRED PLANT -SPECIES IN EACH TWOWEEK AGE DIVISION OF JUVENILE SAGE GROUSE, 1966 AND
1968 (RATED BY PREFERENCE INDICES)........................ 18
VEGETATIVE TYPES AT BROOD LOCATIONS ALONG OBSERVATION
ROUTES IN 1968. ................................................... ..........
19
PERCENT OF BROODS OCCURRING IN DIFFERENT SHRUB
(PRIMARILY SAGEBRUSH) DENSITIES, 1966 AND 1968... ........ .
21
VEGETATIVE MEASUREMENTS TAKEN AT SAGE GROUSE BROOD.
SITES IN 1966 AND 1968 .................................... ..............
33
SHRUB (PRIMARILY SAGEBRUSH) CROWN COVER FOUND WITHIN
BROOD SITES IN 1966 AND 1968. .............. ..........................
22
DISTRIBUTION (PERCENT) OF HEIGHT CLASSES OF SHRUBS
(PRIMARILY SAGEBRUSH) OCCURRING AT BROOD SITES IN 1968... 23
vi
LIST OF FIGURES
Figure
1.
Page
Map showing the study area, and the two vehicle
brood observation routes......................... ...........
7
!
2.
Elevational characteristics of sage grouse brood
locations (benchland vs, bottomland) as found along
observation routes, 1966 and 1968.
- 20
vii
ABSTRACT
The food habits of juvenile sage grouse (Centrocereus Txrophasianus)
were studied in central Montana during the summers' of 1966 and 1968= The
vegetation was analyzed at all feeding sites where birds were collected=
A measure of preference was established for each plant by correlating the
percent volume found in the crops with the percent canopy coverage found
at the feeding sites„ For the two years combined, forbs averaged 75
percent of the diet of 127 juveniles through 12 weeks of age.
Use of
forbs was greater in 1968, apparently due to the above average precipi­
tation and the resulting greater forb cover. The flower buds and leaves
of common dandelion (Taraxacum officinale) and common salsify (Tragapogon dlibius) were the most highly preferred and utilized forbs, compris­
ing 25 and 15 percent of the diets, respectively=
Other forbs commonly
utilized by various ages of juveniles were prairie pepperweed (Lepidivm
densiflorum), prickly lettuce (Lactucg serriola), alfalfa (Medicago
sativa), curlcup gumweed (Grindelia squarrosa), and fringed sagewort
(Artemisia frigida) <> Big sagebrush (Artemisia tridentata) received
little use until the birds were 11 weeks old. Insect use declined
steadily from a high of 60 percent of the diet in one-week chicks to 5
percent .in 12-week-old juveniles. The vegetational and topographical
characteristics of brood sites •'found along two observation routes were
recorded during each week of the study. After the first few weeks of
age, observed brood locations were less frequent on the sagebrushgrassland benches and more frequent on lower areas until by September,
the majority of broods were located on bottomlands.
Sagebrush heights
of 6 to 18 inches were the most prevalent heights at brood sites dur­
ing their morning and evening activity periods.
Important components
of juvenile sage grouse habitat in this area appears to be an abundance
and diversity of forbs and scattered (1-5 percent) or common (5-20
percent) densities of sagebrush.
INTRODUCTION
Range management practices in many areas of the west have shown an
increasing trend toward removal or manipulation of stands of sagebrush.
In light of the potential effect this trend may have on certain game
species, the Montana Fish and Game Department and the United States Bu­
reau of Land Management initiated in 1965 a study to determine the
ecological effects of this manipulation.
As part of this project, my study was conducted during the summers
of 1966 and 1968 to determine the food habits of juvenile sage grouse
(,Centvooerous uroptiasianus) .
Past studies of food habits have indicated a heavy use of forbs and
varying amounts of animal matter by adult sage grouse during the summer
months, as opposed to almost total dependence upon sagebrush during the
late fall, winter, and early spring (Patterson 1952; Batterson and Morse
1948; Griner 1939; and Rasmussen and Griner 1938).
It has also been
shown that juvenile sage grouse rely heavily upon forbs and animal matter
during the first few months of their lives (Klebenow and Gray 1967; Pat­
terson 1952; Griner 1939; and Rasmussen and Griner 1938).
My study placed
emphasis on plant food items with respect to availability of these items,
DESCRIPTION OF THE AREA
The study area is located in central Montana near the town of
Winnett.
This region was described by Gieseker (1938) as having a
semiarid climate, great temperature extremes, and a large number of
sunny days.
The average precipitation for the study area from June
to September each year is 6.74 inches.
During the first summer of ;
ftxe ■
study precipitation was 4.28 below normal, while during the second sum­
mer it was 3.21 inches above.
is 65.4 degrees F.
Average summer temperature for the area
Slightly above normal temperatures prevailed dur­
ing 1966, while those during the summer months of 1968 were below
average (United States Department of Commerce Weather Station at Flat
Willow).
Plants dominating the higher prairie elevations included the
shrubs big sagebrush
(.Artemisva tridentata) and broom snakeweed
(Gutierrezia sarothrae). The predominant forbs were fringed sagewort
(Artemisia frigida), plains pricklypear (Opuntia polyeantha), plan­
tain
phlox
(Plantago spp.), American vetch (Vieia amerieand) > and Hood’s
(Phlox hoodii). Several species of wheatgrass (Agropyron spp.)
were the most predominant grasses.
ed blue grama.
grass
Other common, grass spe'cies includ­
(Bouteloua graaitis), Junegrass (Koleria eristata), blue
(Poa spp.), needle and thread (Stipa oomata), and green
needlegrass
(S> viridula) .
The lower elevations, especially those adjacent to creek bottoms,
were often dominated by shrubs such as big sage, silver.sage
(Artemisia
oana), greasewood (Saroobatus vermieulatus), and rubber rabbitbrush
(Chrysothamnus nauseosus). Common dandelion (Taraxieum officinale) ,
—3—
yarrow
(AchrLtZea mLttefolLim), and curlcup gumweed (GvLndetrLa squar-
vosa), were common forbs.
at the lower elevations.
Wheatgrasses were the major grasses found
Others commonly found were foxtail barley
(Hovdeum jvibatwn) t brome (Bvomus spp.) and desert saltgrass
(DLstLehtis stvieta) .
Many of the stream bottoms have been planted to alfalfa
(MedL-
eago sativa), whereas the adjoining sagebrush-grasslands are used
almost exclusively for livestock grazing.
METHODS
Initially, all portions of the study area were searched by ve­
hicle fol sage grouse broods during the morning and afternoon activity
periods.
Morning searches were later abandoned after it was discov­
ered that crop contents were minimal from birds collected at this
time.
Collections made from about an hour before sundown until dark
provided more adequate crop volumes.
Most collections were made with either a .22 caliber rifle or a
.410 shotgun.
Chicks less than two weeks old were easily caught b y .
hand.
Each collection was made in essentially the same manner.
After
a brood was discovered, the birds while feeding were carefully ob­
served with the aid of a 15-60% variable spotting scope and/or a 7 x 35
binocular.
Observations were made for approximately 30 minutes at a
sufficient.distance to prevent disturbance.
At the end of this period,
I collected one of the chicks, marked the feeding area with stakes for
later vegetational analysis and briefly described the vegetational
and physical characteristics of the site.
The age of each collected bird was determined by measurements of
certain external features:
tail length, foot length, leg length, .and
the stage of molt found on the primary wing feathers (Eng 1955; Pyrah
1963).
Sex was determined by internal examination.
saved from each bird for reference.
One wing was
Both.the crop and gizzard were
marked and preserved in 10 percent formalin.
Crop and gizzard analyses were conducted after the field season.
Normally only the crop was considered since the items found in it
— 5—
should have been most representative of items being fed upon immedi­
ately prior to collection.
Measurements of food items were made volu-
metrically by the displacement of water.
Measurements within each age
class were grouped.by use of the aggregate volume method (Martin
1946).
et .al.
Supplemental crops were obtained during both years from pre­
dator and road kills throughout.the summer and hunter-killed birds on
the opening day of grouse season.
Vegetation analysis of the feeding area at each■collection site
took place within several days.
A method similar to that.used by
Daubenmire (1959) was utilized to determine canopy coverage.
2 x 5
Twenty,
decimeter plots were placed at five-foot intervals along a
hundred-foot tape.
This tape was. placed as close as possible along
the observed path the brood used while feeding.
Within these plots,
the coverage of each plant species was visually determined and re­
corded into classes.
The coverage classes used in 1966 were:
Class I
= 0-5 percent; Class 2 = 5-25 percent; Class 3 = 25-50 percent; Class
4 = 50-75 percent; Class 5 = 75-95 percent; and Class 6 = 95-100 per­
cent.
The midpoints of these classes were used in analysis of data.
The coverage classes used in 1968 were similar to those just mentioned,
but slightly refined for greater ,accuracy.
Additional information in­
s'
eluded in the 1968 analysis was the recording of the heights and
phenology of all plant species occurring within the 2 x 5
plots.
decimeter
Shrub (primarily big sagebrush) characteristics such as canopy,
coverage and average heights, were recorded by the use of the line
-6intercept (Canfield 1941) along the hundred-foot tape.
The amount■of
bareground, moss, lichen, rock, and litter was also recorded.
Plant
nomenclature is that of Booth (1950) and Booth and Wright (1959).
Two vehicle brood routes which followed roads and trails through
sagebrush-grasslands with an interspersion of benchland and stream bot­
toms, were traversed once a week throughout.the summer. ■ The War Horse
route, 45.1 miles in length, was north of Winnett and the Yellow Water
Triangle route, 50.4 miles, was south of Winnett (Figure I).
These
routes were used only in the morning to facilitate comparison and to
reserve late afternoons for chick collections.
Each route was begun
at or near sunrise on mornings when relatively clear, calm weather pre­
vailed.
The vehicle was driven at 15-20 mph and route coverage was'
usually completed before the broods ceased their morning activities.
To prevent bias caused by the length of the routes, they were driven
in alternate directions every other week.
When a brood was observed the birds were flushed, counted, and
the spot where the hen was first seen was marked with a stake.
Nota­
tion was then made of the characteristic features of the surrounding
area in the same manner as described for chick collection sites.
After a route was finished, vegetation analysis- was conducted at
each brood site.
The methods employed were basically similar to those
used at the collection sites, but modified to suit conditions.
One modification involved the measurement of canopy coverage.
2 x5
decimeter plot frame was placed at 10-foot.intervals along two
The
iiiT m
i
t
Figure I.
inn
mil
Hill m
HIu imrn
IlIIIIWI
win min
muun
Map showing the study area and the two vehicle brood
observation routes.
-8“
50-foot steel measuring tapes.
The center of the tapes crossed at 90
degree angles over the stake which marked the location of the hen.
To
prevent bias in placement, one tape was placed perpendicular to the
roadway used by the vehicle.
In 1968, a modification was implemented when measuring a brood
site in a roadside ditch.
The center of the crossed tapes .was placed
in the center of the ditch and the angle adjusted so the tape ends fell
on the edges of the ditch.
Thus, all the measurements recorded were
within the roadside ditch and more accurately portrayed the vegetative
type in which the birds were actually feeding.
In 1966, segments of
the vegetative sample which fell on the road were deleted.
Thus, sites
measured between the years were comparable, but sample sizes on
certain individual sites in 1966 were smaller.
Another difference existed in measurement of shrub intercept be­
tween 1966 and 1968.
In 1966 an 11.7-foot chain was used as the radius
with the hen location as the center.
Measurements were made by placing
the chain on radii to cardinal points and recording the shrub intercept
along the chain.
The number, average height, and average diameter of
the shrubs found within the circle formed by ,the chain were determined.
In 1968, a larger sample was obtained by measuring shrub intercept,
height, and density along two perpendicular 50-foot tapes.
RESULTS
FOOD HABITS
Crop Content Analysis
During the two summers of the study, I analyzed the crop contents
from 151 juvenile and 32 adult.sage grouse.
The juveniles were separated
into weekly age classes, and,the source and age distribution of 127 birds
through 1 2 -weeks is presented in Table I.
The frequency and volume of
food items found in these birds are presented by two-week age divisions
in Table II.
TABLE I.
SOURCE AND AGE DISTRIBUTION OF 127 JUVENILE SAGE GROUSE, AGES
I THROUGH 12 WEEKS, 1966 AND 1968.
Age in Weeks
1966
Intentional
Collection
Road Kill
Hunter Kill
Sub-total
1968
Intentional
Collection
Road Kill
Hunter Kill— '
Predator Kill
(I) (2) (3) (4) (5) (6) (7) (8)
(9) (10)
(11) (12) Total
-
5
-
4
-
2
-
5
2
4
I
5
I
4
2
5
8
I
4
2
I
-
4
3
3
3
3
41
23
8
0
■_
5
4
2
7
5
6
6
14
7
7
9
72
3
2
7
I
.4'
I
3
I
5
2
2
3
2
3
44
9
2.
2
3
7
-
-
-
-
-
-
I
Sub-total
2
2
4
7
5
GRAND TOTAL
2
7
8
9
12
-
-
I
8
-
6
4
7
2
13 -4 2
40
,21
■9
-
-
2
3
55
12. , I?
127
5
I/ No birds younger than 14 weeks' old were collected -at the.hunter
checking station in 1968.
.
TABLE II.
PEkCEMT FREQUENCY AND VOLUME OF FOOD ITQlS COMMONLY UTILIZED BY I- THROUGH 12-WEEK-OLD SAGE GROUSE COLLECTED DURING 1966 AND 1968.
Age in Weeks
Nunber of Birds
Plant Matter
(I &
9
2)
fr/vo^/
(3 & 4)
17
(5 &
25
6)
(7 &
8)
I/
(9 & 10)
30
(11 & 12)
22
24
fr/vo
fr/vo
fr/vo
fr/vo
fr/vo
-
4/tr
28/1
4/tr
24/2
3/tr
30/8
13/1
71/29
FORBS
Achillea millefolim
Artemisia frigida
Camelina microcarpa
Grindelia squarrosa
Laotuca serriola
Lepidim densiflorm
Medicago sativa
Taraxacm officinale
Tragopogon diibius
Unidentified Forbs
SHRUBS
Artemisia tridentata
Bius trilobate
~
-
18/2
6/tr
~
8/1
41/4
32/3
45/20
78/40
—
44/13
33/tr
56/5
18/3
—
82/52
59/19
18/1
4/1
24/1
68/32
84/35
32/2
18/3
50/14
82/24
23/tr
-
12/tr
4/tr
-
-
-
5/7
-
-
-
-
-
-
-
0
2
0
17/6
5
I
2
76
90
12/tr
-
11/tr
-
-
-
-
23/2
67/37
54/6
54/14
3/tr
23/2
47/18
53/8
27/tr
21/3
38/20
67/2
33/1
23/tr
58/6
_
GRASSES
Tritiem aestivm
Other Plant 3/
TOTAL PERCENT PLANT V O L W E
63
77
77
75
0
1
Anlaal Matter
Coleoptera
Hymenoptera
Immature Insects
Orthoptera
Unidentified Insects
Other Animal 4/
TOTAL PERCENT ANIMAL VOLWE
78/11
87/5
67/8
33/tr
44/tr
13
77/4
65/9
41/1
24/3
24/3
3
64/1
60/2
32/1
44/18
32/1
0
37
23
23
6/tr
40/tr
40/24
10/tr
29/tr
50/tr
0
0
24
24
0
10
23/1
41/tr
14/tr
36/23
9/tr
—
33/10
8/tr
I/ Other food !tons utilized by the chicks but which did not represent more than a trace of the volume (less than I cc.) in any individual age
_ division, are listed here: Forbs - Artemisia ludoviciana. Astragalus spp., Laatuaa pulahella, Legminosae (unidentified), Melilotus offici­
nalis, Medicago lupulina, Orobanche fasciculate, Potentilla spp., Sisynibrim loeselii, Solidago missouriensis, Trifolim spp., and Vicia
cmericana; Shrubs - Artanisia cana, Rosa spp., and certain unidentified shrubs; Grasses - species not identified; G rass-1ik e - Carex spp. ;
Animal - Arachnoidea, Diptera, Hemiptera, Homoptera, Lepidoptera, Odonata, and Plecoptera.
2/ fr/vo - percent frequency/percent volume.
3/ Percent volume of plant matter obtained by the combined measurement of those species found in trace quantities (less than I cc.).
4/ As 3/.
I
H
-11Although grouse older than 12 weeks were collected, the primary in­
terest of this study centers around the food habits of juveniles and
this age was decided upon as a suitable breaking point.
Rasmussen and
Griner (1938) found the food habits of:juveniles to parallel those of
adults after three months of age.
The results of the food analysis of
adults and juveniles 13 weeks and older are presented in the Appendix,
Table III.
Considering all birds through 12 weeks of age, the average diet
during the two summers consisted of 76 percent vegetable and 24 percent
animal matter (Table II).
The two most important plant items in the diet throughout the two
summers were common dandelion and common salsify
(Tragopogon dubius).
Dandelion was found in 55 percent of the grouse analyzed, and salsify
was found in 63 percent, while both averaged the two largest individ­
ual crop volumes of all juveniles for both years.
Five other commonly utilized plants appeared to be more periodic
in their occurrence in the diets of the chicks.
Prairie pepperweed
(,Lepidium densiflovim) was very important in the younger age classes.
During the first five weeks, this item was utilized by 44 percent of
the grouse and averaged 15 percent of the total volume, while ocurring in only trace amounts in older birds.
gumweed, prickly lettuce
Fringed sagewort, curlcup
(Labtuca sevviola) , and alfalfa were not
f■
utilized to any extent until the fifth or sixth week.
Prickly lettuce
did not appear in the diet until.the sixth-week class after which it
-12was found in 49 percent of the birds and averaged 21 percent of the
total volume.
Similarly, fringed sagewort occurred only in trace
amounts in a few birds up until the sixth-week class, while thereafter
it occurred in 45 percent of the crops and comprised 11 percent of the
average crop volume.
Big sagebrush never became an important constituent of the chicks'
diet, occurring in only 16.percent of the birds and averaging I per­
cent of the total volume for both summers.
Traces of this shrub (the
leaves) were found in younger birds, but it only occurred in quantity
in chicks over 10 weeks of age.
Animal matter (primarily insects) was the most important constitu­
ent of the diet during the first week of age, totaling 60 percent of
the crop volume.
However, this sample consisted of only two chicks.
This high animal use dropped to 33 percent of the volume in the twoweek birds.
The percentage of animal matter in the diet for the next
four age groups remained quite constant but at a lower, level.
In the
12-week birds, this animal percentage dropped to 5 percent of the total
crop volume.
Orthoptera (primarily grasshoppers), Coleoptera (beetles), and
Hymenoptera (primarily ants), were the most important insects in the
diet.
Ants were utilized heavily by the early-week classes, but their
small size added little to the volume.
They were found in 71 percent
of the crops and averaged 5 percent of the volume of the one- through six-week chicks; however, they had a frequency of 44 percent
-13and were found in only trace amounts in the 7- through I2-week-old birds.
Beetles occurred in nearly every week class during the entire summer and
in 46 percent of all chicks,
However, only 19 percent of the juveniles
from 7- through 12-weeks of age ate beetles, while 73 percent utilized
this group of insects during the first six weeks, where they averaged
5 percent of the crop volume.
Grasshoppers made the largest contribution to the animal portion
of the diet.
They occurred in 35 percent of all grouse and constituted
13 percent of the total diet.
Heavy utilization of grasshoppers began
primarily in the five-week chicks.
Up to this age, this insect oc­
curred in 29 percent of the juveniles, but averaged only 2 percent of
the total crop volume.
In 5- through 12-week-old birds, they occurred
in 38 percent of the crops and averaged 19 percent of the volume.
A marked contrast was observed in the diet between the two years
(Table IV), a contrast which is masked in the combined data presented
in Table II.
The two major plant items and the predominant animal
item were selected for comparison.
The percentage of salsify utilized was found to be closely compar­
able between the two years.
The amount of dandelion found in the crops
in 1968 was over twice that found in 1966.
Grasshoppers were very promi­
nent in the crops of birds collected in 1966, but only occurred in trace
amounts in 1968.
TABLE IV.
/
I
DIFFERENCES IN AMOUNT OF COMMON,FOOD ITEMS FOUND IN THE
DIETS OF JUVENILE /SAGE GROUSE BETWEEN 1966 AND 1968.
_________________________ /
I_ _ _ _ _ _ I
Age in Weeks
(1&2)
(9&10)
(3&4)/ (5&6j) (7&8^
1966
%
%/
%
% ,
% /
Vol.
Wk.
vdi. . Vol. Vol.
No. of Chicks
5
W
w
20
46
5
Al
6
33
Food Item
Salsify
Dandelion
Grasshopper
tr
17 ■
tr,
1968
No. of Chicks
4
10
tr
tr
64
(11&12)
'12/
21
%
Vol.
16
32
6
44
515
31
2
4
22
10'
9
8
21
30
—
2
33
~
(Average)
%
Vol.
W
rO
17
16
23
Food Item
Salsify
Dandelion
Grasshopper
17
tr
29 ;
62,
tr
16
23
-
14
35,
tr
Food Item Preference
In a food habits study, the availability of an item and its ob­
served use by the animal are two of the more important factors to be
considered.
The vegetative composition of 81 grouse collection sites
is presented in the Appendix, Table V.
In Table VI, the percent volume
of each plant food item found in the crops is correlated with the per­
cent canopy coverage of each item in the feeding area.
To establish a relationship between these two factors, the percent
canopy coverage of a particular plant was divided into the percent vol­
ume which that plant composed in the crop.
The quotient was used as a
preference index number, the larger the index number for a given food
TABLE VI.
PREFERENCE INDICES "ASSIGNED TO PLANT FOOD ITEMS FOUND IN THE CROPS AND AT THE FEEDING
SITES OF 81 JUVENILE SAGE GROUSE COLLECTED DURING THE SUMMERS OF 1966 AND 1968.
Age in Weeks
No. of Birds
Taxa
(I & 2)1/
(5 & 6)
(7 & 8)
(9 & 10)
(3 5= 4)
14
17
16
11
8
2/
Vol./Cov.-/ Vol./Cov. Vol./Cov. Vol./Cov. Vol./Cov.
= Rating = Rating = Rating = Rating
= Rating
(13 5= 14)
6
Vol./Cov.
= Rating
11/000.1
110.0
44/ 4.90
= 8.98
40/ 2.65
=15.10
16/ 3.35
= 4.78
2/ 1.55
= 1.29
49/13.9
=03.54
I/ 2.3
= 0.43
I/ 2.8
15/ 8.95
34/14.6
= 2.33
44/ 7.4
= 5.95
I/ 5.5
0.18
—
= 1.68
2/ 1.85
= 1.08
-
5/ 5.45
= 0.92
tr/ 0.11
= 0.91
53/ 29.8
= 1.78
tr/ 0.75
= 0.06
-
= 0.36
-
-
-
-
-
tr/ 0.35
-
-
-
—
-
-
-
15
Tragopogron
26/ 2.45
tf/000.05
= 2.00
L0.60
dub-ins
66/12.4
Taraxacum
24/ 0.6
= 40.0
= 5.32
officinale
tr/ 1.40
tr/ 2.65
Grindelia
= 0.04
squarrosa
= 0.07
Lepidiim
64/ 1.70
6/ 1.7
densiflonm
.= 37.65
= 3.53
tr/ 5 . 3 5 ^
Vicia
= 0.02
americana
Camelina
2/ 0.3
= 6.67
microcoorpa
Laetvuca
pulehella
tr/ 5.0
Artemisia
frigida
= 0.02
Artemisia
tr/ 7.3
= 0.01
tridentata
Laetvuea
serriola
—
Artemisia
ludovieiana
Achillea
millefolium
(11 & 12)
9
Vol./Cov.
= Rating
= 0.29
I/ 0.15
= 0.67
2/ 4.7
= 0.43..
tr/ 1.05
= 0.10
7/ 5.15
= 1.36
16/ 3.3
= 4.85
42/ 7.65
= 5.49
21/
=
2.85
7.37
-
tr/ 0.8
= 0.13
24/ 9.5
= 2.53
I/ 4.0
= 0.25
tr/ 0.15
= 0.67
-
I/
=
tr/
=
3.3
0.3
0.4
0.25
2/ 1.35
1.48
tr/
=
tr/ 4.8
= 0.02
I/ 0.01
=100.00
22/ 0.65
=33.85
tr/ 0.35
= 0.29
tr/ 2.1
= 0.05
tr/ 5.05
= 0.02
-
-
-
-
1.95
0.05
TABLE VI=
(CONTINUED).
Age in Weeks
No. of Birds
Taxa
(I & 2)
Vol .IGov.
= Rating
Medrleago
soitiva
Trifotiim
4)
(7 & 8)
(5 & 6)
(9 .& 10)
16
11
17
Vol.Gov. Vol./Cov. Vol./Gov. Vol./Gov.
= Rating •= Rating = Rating = Rating
(3 &
14
8
-
-
-
tr/ 3.55
= 0.04
■
'
tr/19.0
= 0.01
—
—
—
—
-
-
,-
spp.
Metitotvs
offieinatis
Hhvs
trilobata
Carex
spp.
Gramineae
I/ 1.15
= 0.87
—
—
-
tr/ 2.51
= 0.05
I/ 5.75
= 0.17
(11 & 12)
9
Vol./Cov.
= Rating
5/ 8.55
= 0.59
7/ 4.05
= 1.73
-
-
tr/17.15
= 0.01
tr/11.0
= 0.01
tr/ 8.75
= 0.01
13/ 0.85
=15.29
-
—
-
-
-
-
tr/68,65 tr/69.9
tr/79.5
= 0.001
= 0.001
= 0.001
tr/58.6
= 0.001
• (13 & 14)
6
Vol./Cov.
= Rating
13/
=
-
24.95
0.52 ■
—
tr/ 15.55
== 0.01
—
tr/
=
.
0.20
0.50
tr/ 63.0
=
0.001
I/ Unidentified forbs constituted 12 percent of the volume in the I- and 2-week-age division.
2/ Vol./Cov..= percent volume (divided by) percent canopy coverage.
_3/ Tr - given a value of 0.1 percent volume for each species.
-17item, the greater the1preference.
For example, in the first age divi­
sion, dandelion was the most sought after plant, recording the largest
index number (40.0).
The five most preferred plants utilized by each two-week age divi­
sion of chicks are placed in Table VII.
They are numbered from five
through one in descending order of their importance.
An indication of
the preference for major plant species during the entire summer was ob­
tained by adding together each preference number a species received in
every age class.
Differences in physical structure between plant species will lend
a certain degree of error to these data.
For example, leaves were the
most common part of dandelion found in the crops although flower, buds
were readily taken at the few sites where they occurred.
were the main parts taken from salsify.
Flower buds
It would take many dandelion
leaves from several plants to equal the volume displaced by one or two
salsify flower buds from one plant.
This could tend to give salsify
a higher preference rating than dandelion at certain sites, even if a
chick spent equal or more time eating dandelion leaves. .However, since
it is the contention of this study to give the availability and abun­
dance factor of each plant species as much consideration as possible
in the selection of food items by juvenile sage grouse, the method
used was selected as being the most adequate.
The results of these
preference ratings are somewhat similar to those obtained when crop
contents only were considered.
-18TABLE VII.
THE FIVE MOST PREFERRED PLANT SPECIES IN EACH TWO-WEEK AGE
DIVISION OF JUVENILE SAGE GROUSE, 1966 AND 1968.
(RATED
BY PREFERENCE INDICES). I/
Age in Weeks
Tragopogon
diTbius
Tccraxaawn
officinale
Artemisia
frigida
Laatuoa
serriola
Mediaago
sativa
Lepidivm
densiflorwn
Grindelia
squarrosa
Camelina
miaroaarpa
Achillea
millefolium
Vioia
amerioana
Laotuoa
puldhella
Carex
(1&2)
(3&4)
(5&6)
3
5
4
41/
4
I
5
26
5
3
3
3
2
5
3
24
2
5
4
4
15
5
3
5
(7&8)
(9&10)
2
(11&12) (13&14)
13
3
4
2
-
—
2
I
-
I
4
-
—
.
(T) 2/
2
7
-
6
I
-
-
5
-
-
-
4
_
_
I
—
-
-
-
-
I
2
2
—
—
I
-
-
-
-•
I
—
™
-
-
-
-
I
I
spp.
I/ The number assigned to each species, in descending order of
importance, indicates its status as a preferred plant food item.
2j (T) - Total number of preference points for each species.
3/ Khva tTitobata has the second highest index number in the seventhrough eight-week division, but was not considered as it only
occurred in the crop of one bird.
BROOD DISTRIBUTION
To supplement the food habits study, data were gathered relative to
the spring and summer distribution of sage grouse broods.with respect to
vegetative types along two observation routes.
These data were separated
-19Into two major groups;
(I) the gross vegetational and topographical
features of areas in which the broods were located, and (2) a specific
analysis of the brood site*
Gross Vegetational and Topographical Features
The general vegetative types in which broods were located, ob­
tained only in 1968, are presented for each month (June through Sep­
tember) in Table VIII.
The average percent of each type found along
both observation routes is also presented.
The sagebrush-grassland
type received the highest average use for the entire summer.
Use of
this type decreased from 100 percent in June to 50 percent in Septem­
ber.
Corresponding with this decrease was an increased use of grease-
wood and grassland types.
This increase, particularly in the case of
greasewood, was correlated with brood movements from higher benchland
types, to more mesic bottomland sites as the summer progressed
(Figure 2).
table
viii.
Vegetative
types at brood locations along observation
ROUTES IN 1968.
Number
Percent
of
Sag eb rush-Gras sland
Sites
[6911/
VEGETATIVE TYPE
Percent
Percent
Grassland
Greasewood
[10]
[14]
Percent
Misc.
[8] .
MONTH
June
(H)
July
(19)
August
(16)
September( 4)
100
74
63
50
5
18
25
11
18
25
11
.-
I/ The average percent of each vegetative type found along, both routes.
Percent Benchland Occurrance
LEfflND
August
Figure 2.
September
Elevational features of sage grouse brood locations (benchland vs. bottomland) a«
found along observation routes, 1966 and 1963.
“21The different degrees of shrub density found at brood locations
along observation routes are presented in Table 1X«
Sagebrush densi­
ties of 5 to 20 percent were most commonly used during both summers.
TABLE IX,
PERCENT OF BROODS OCCURRING IN DIFFERENT SHRUB (PRIMARILY
SAGEBRUSH) DENSITIES, 1966 AND 1968.
June
Percent
Density™'
(1966) (1968)
3
No, of Broods 8
—
Absent
(none present)
12
Rare
(present)
Scattered
25
—
July
Percent
(1966) (1968)
23
19
17
11
26
11
33
17
67
August
Percent
(1966) (1968)
26
16
43
18
16
31
18
35
51
23
63
5
11
4
September
Percent
(1966) (1968)
3
4
25
(1-5%)
Common
(5-20%)
Dense
50
12
100
75
'
(20-40%)
Il/ Determined from visual observation in the immediate area of each
feeding site.
Individual Brood Sites
Ninety-one Daubenmire transects were run at brood locations along
the observation routes during both summers.
The vegetative measure­
ments gathered at each of those sites have been combined for each month
and compared between years in the Appendix, Table X,
The combined canopy coverage of forbs for both summers averaged 33
percent.
The 39 percent coverage in 1968 was considerably higher
-22than the 26 percent in 1966 (June was excluded since no transects were
run during that month in 1968).
This difference was particularly promi­
nent during July when over twice as much forb,cover was present at brood
sites in 1968 (53 percent) than was present in 1966 (25 percent), and
again in August, when forb cover was three times greater in 1968 (48
percent) than in 1966 (16 percent).
This trend appeared reversed in
September, but this may have been due to the small sample obtained.
The abundance of sweet clover
(Melilotus officinalis) was the
single biggest reason for forb cover being greater in 1968 than in 1966.
In 1966, this plant provided a cover of 8 and 3 percent for July and
August respectively, while in 1968 it composed 22 percent of the cover
for each of these months„
The crown coverage of sagebrush occurring on brood sites is re­
corded in Table XI.
The combined data for the two years show an average
sagebrush cover of 6 percent from June through August, increasing to an
average of 12 percent during September.
TABLE XI.
Month
June
July
August
September
SHRUB (PRIMARILY SAGEBRUSH) CROWN COVER FOUND WITHIN BROOD
SITES IN 1966 AND 1968.
Number
of Sites
( 8)
(37)
(39)
( 7)
Percent Sagebrush Crown Cover
(1968)
(1966)
4
5
6
13
I/ No vegetational analyses were conducted during June, 1968.
-I/
7
5
11
-23The average heights of the sagebrush stands found at brood sites
in 1966, increased from an average of 16 inches in June to 20 inches in
September.
In 1968, more meaningful data were obtained by placing shrubs
into height classes (Table XII).
Sagebrush heights of 6 to 12 and 12 to
18 inches were the dominant height classes at brood sites each month.
In Montana, Martin (1965) found big sagebrush plant heights ranging from
9 to 15 inches at locations of young broods.
TABLE XII.
Month
I/
July
August
September
DISTRIBUTION (PERCENT) OF HEIGHT CLASSES OF SHRUBS (PRIMARILY
SAGEBRUSH) OCCURRING AT BROOD SITES IN 1968.
Number
of
Sites
(19)
(16)
( 7)
0-6
%
10
3
17
6-12
'%
44
24
40
HEIGHT CLASSES IN INCHES
12-18
18-24
24-30
%
%
%
39
46
17
4
15
7
4
7
20
30 plus
%
0
7
0
_!/ June was omitted since no vegetative analyses were conducted during
that month.
DISCUSSION
The data leave little question as to the importance, o f .forbs in the
summer diets of-juvenile sage grouse.■ The availability of, and seeming
preference for parts of certain forbs, played an important role in the
seasonal use of these plants as well as the distribution of the birds.
The higher utilization of dandelion in 1968, as compared to 1966,
was apparently due to above normal precipitation, which resulted in.
this forb being a very common component of the flora at most brood lo­
cations.
This may have been an important factor in the wide brood
distribution throughout the sagebrush-grassland areas during the summer
months of 1968.
The seed pods of prairie pepperweed were a very impor­
tant constituent'" of the diet of the youngest grouse.
of this plant placed these pods within easy reach.
The small size
In m o s t ,instances,
this plant became desiccated and unavailable as a food source by the
time the chicks.were five or six weeks old.
Availability ■also.ap­
peared to be the main factor governing the use of prickly lettuce.
Although a few leaves of this, plant were taken earlier, the flower
buds became available near the end of July and were heavily utilized
by August,
Although this plant began to desiccate in certain areas
and become less available by the first of September, it still con­
stituted an important item in the diet of birds 11 through 12 weeks of
age.
Availability did not appear to be the most important factor gov­
erning the utilization of fringed sagewort. ■ Although this species
w a s ■commonly found at nearly every feeding site and/or brood location
-25during each month of the study, it did not appear in the .crops until
the fourth week class, where it was present only as a trace.
Thereafter
each successive week class of juveniles utilized increasingly larger
amounts of fringed sagewort leaves until the 11- and 12-week division.
The juveniles’ increased use and apparent preference for fringed sagewort with the advance of summer, may be related to their future diet.
Since fringed sagewort is a close relative of big sagebrush, it con­
ceivably might be used as a transitional food item between the summer
diet consisting of forbs and the winter diet of big sagebrush.
Contrary to previous studies (Rasmussen and Griner 1938 and Pat­
terson 1952), I found the use of big sagebrush as a food source, to
be very minimal among juvenile sage grouse during the summer.
The
leaves averaged I percent of the total diet of 127 juveniles through
12 weeks of age.
Increased use of this plant.was noted in the later
week classes, composing as much as 11 percent of the diet in the 11week-old juveniles.
However, it only comprised I percent of the crop
volume in 12-week-old birds.
Although some use of alfalfa was noted by five- and six-week
chicks feeding in borrow pits or other disturbed areas, this plant
was not utilized to any extent until later in the summer when many
of the birds began feeding in hay meadows.
Even then, alfalfa never
became more than the third most preferred plant food item or com­
prised more than 3 percent of the volume in any given age division.
When I observed and collected juveniles feeding in alfalfa fields,
— 26 -
dandelion and salsify were quite frequently the major items in the crop.
Thus, it would appear that in most instances sage grouse are attracted
to hay meadows by the lush vegetational aspect, and not specifically
to alfalfa as a food item.
Grass occurred in nearly every age class, but never constituted
more than a trace of the volume in any bird.
It is believed that most
of this use occurred incidentally while feeding on other species.
Considerable difference was observed in the percentage of animal
matter in the diet between 1966 and 1968.
This difference was attrib­
uted to heavy utilization of grasshoppers in 1966, which in 1968
constituted only a trace.
There appeared to be an abundance of grass­
hoppers present during m o s t .of the 1966 summer season.
Most of the
plants on the study area became desiccated early that year.
This con­
dition tended to concentrate both grouse and grasshoppers, into common
areas of succulent vegetation, and therefore made this insect group
readily available to the birds.
By .contrast, in 1968, the grouse
were still highly distributed throughout the study area during midand late summer, presumably due to the above normal precipitation
and resulting forb cover.
If the grasshopper population was also
highly distributed, there would be less chance of high numbers of
grasshoppers being available to individual birds, even if the insect
population was the same for both years.
It can be readily ascertained from this study that during the sum­
mer, juvenile grouse are highly dependent upon forbs for food and uti-
-
21* -
Iize sagebrush in scattered or common densities for cover.
Further,
a desirable forb composition would be one which is sufficiently di­
verse to provide a variety of succulent plants as the season progresses.
Therefore, range manipulation which would eliminate sagebrush and reduce
the abundance and variety of.forbs, would lower the ability of this
range to support juvenile sage grouse.
APPENDIX
TABLE III.
PERCENT VOLUME AND FREQUENCY OF COMMON PLANT AND ANIMAL FOOD ITEMS FOUND IN'SAGE
GROUSE JUVENILES 13 WEEKS AND OLDER AND ADULTS IN 1966 AND 1968.
Age
Year
Number of Birds
Food -Items
PLANT
Artemisia frigida
Artemisia tx^Ldentata
Laotuoa serriota
Medioago sativa
Taraxaoun officinale
Tragopogon dubius
ANIMAL
Orthoptera
I/
THIRTEEN WEEKS
AND OLDER
(1968)
(1966)
10
f/v
;%/
ADULTS
August
(1968)
(1966)
15
3
f/v
f/v
94%
100%
62%
100%
32/27
44/ 4
51/42
6/1
44/16
21/1
20/tr
10/tr
50/34
80/12
90/44
60/10
60/12.
40/10
40/22
13/ I
40/11
• 53/ I
67/10
33/tr
33/tr
67/15
100/54
67/19
6%
tr%
38%
60/34
37/ 6
-
September
/
(1966)
(1968)-'
12
2
f/v
f/v
100%
100%
25/ 2
17/ 3
58/70
8/tr
17/ I17/tr
50/ 3
100/ 3
tr%
tr%
tr%
-
-
-
100/ 8
100/ 3
AohyLtZea miltefoH i m (,leaves) supplied 75 percent of the volume of September.adults in
1968.
2/ f/v = percent frequency/percent volume.
-
TABLE V.
VEGETATIVE COMPOSITION FOUND AT 81 JUVENILE SAGE GROUSE COLLECTION SITES, WITH
EMPHASIS ON THE MORE COMMONLY OCCURRING PLANT SPECIES.
I/ (1 5 2)
No. Feeding Sites=/
8 _.
Taxa
cy/fr/cv—
FORBS:
100/92/33
AehiVlea
38/ 6 / 1
miVlefoiium*
Androsaee
septentrionalds 50/ 3/tr
Arenaria
25/ 4/ I
hookeri
Artemisia
100/35/ 8
friqida*
Artemisia
13/ 3/tr
ludovieiana*
Camelina
18/ 2/tr
mieroearpa*
Erigeron
63/ 6/,I
ipimilvs
Grincielia
38/16/ I
squarrosa*
Laetuea
25/ 2/tr
serriola*
Laetuea
pulehella*
Lepidium
36/24/ 2
densiflorum*
Medieago
sativa*
Opuntia
38/ 5/tr
polyeantha
Phlox.
25/13/ 2
hoodii
AGE IN WEEKS
(7 & 8)
(9 & 10)
16
11
cy/fr/cv
cy/fr/cv
(3 & 4)
14
cy/fr/cv
(5 & 6)
17
cy/fr/cv
100/99/47
100/96/49
100/86/47
100/93/50
48/ 8/ I
40/15/ 5
52/ 9/ 3
27/ 8/ 2
28/ 2/tr
24/ 3/tr
11/ 1/tr
11/ 1/tr
13/11/ 2
6/ 1/tr
7/ 1/tr
59/24/ 5
66/24/ 5
70/19/ 5
53/15/ 3
6/ 1/tr
21/5/ 2
7/ 4/ 2
25/ 4/tr
18/ 4/tr
11/ 3/tr
15/ 2/tr
12/ 2/tr
53/17/ 3
57/11/ 2
50/ 7/ 2
68/17/ 6
59/24/ 6
50/ 8/ I
19/ 9/tr
11/ 1/tr
35/ 5/ 2
41/24/10
9/ 1/tr
33/ 4/tr
-
13/ 2/tr
11/ 5/ I
20/ 5/ I
-
-
53/17/ 2
47/16/ 3
31/ 6/ I
32/ 3/tr
-
-
7/ 1/tr
18/ 5/ I
32/ 9/ 6
35/17/ 9
42/14/ 4
50/46/25
—
24/ 2/tr
18/ 3/tr
20/ 1/tr
50/ 5/tr
34/ 4/ I
__
7/ 1/tr
11/ 2/tr
-
-
-
(11 & 12) (13 & 14)
9
6
cy/fr/cv cy/fr/cv
100/96/32 100/97/60
42/13/ I
—
9/ 2/tr
75/31/ 8
33/ 7/ 2
—
50/24/ 3
-
-
-
-
-
-
-
9/ 1/tr
17/ 2/tr
TABLE V.
(CONTINUED)
(I & 2)
(3 & 4)
14
8
No. Feeding Sites
cy/f-r/ov .. ' cy/fr/cv
Taxa
AGE IN WEEKS
(7 & 8)
(5 & 6)
17
16
•cy/fr/cv-. cy/fr/cv
(9 & 10)
11
cy/fr/cv
(11 & 12) (13 & 14)
9
6
cy/fr/cv cy/fr/cv
39/ 8/ I
42/ 9/tr
FORBS-(cont.)
Plantago
spp.
Sphaeraloea
coooinae
Taraxacum
officinale*
Thlaspi
arvense
Tragopogon
dubius*
Vicia
americana*
SHRUBS:
Artemisia
■ cana ,
Artemisia
tridentata*
Atriplex
nuttallii
Chrysothamnus
nauseosus
88/25/ I
28/ 8/tr
47/13/ 4
43/17/ 2
13/14/tr
7/ 1/tr
24/ 3/ I
20/ 5/ 2
-
13/ 2/tr
-
34/ 6/tr
—
14/ 2/ I
18/ I/ I
9/ 1/tr
-
75/16/ I
50/13/tr
54/ 9/ I
31/ 6/ I
7/ 1/tr
25/ 4/tr
17/ 3/tr
63/ 7/ I
60/30/12
76/41/14
53/33/ 9
73/32/15
84/46/ 7
67/45/30
16/ 3/tr
17/ 3/tr
18/ 7/tr
13/ 1/tr
63/17/tr
66/18/ 5
78/12/ 3
60/17/ 3
50/13/ 2
50/ 4/tr
75/30/ 5
71/20/ 3
41/ 8/ I
62/10/ I
27/ 2/ I
33/ 6/tr
17/ 1/tr
100/43/16
63/25/8
72/18/ 7
56/11/ 4
60/ 9/ 3
15/19/ 4
34/16/ 4
—
21/ 4/ I
11/ 2/tr
7/ 1/tr
38/ 8/ 2
27/ 3/ I
75/40/15
-
42/16/ 7
32/13/ 3
54/11/ 5
-
5/ 1/tr
-
-
-
7/ I/ I
-
-
—
50/17/ 4
-
34/13/ 3
-
TE-
spp.
Psoralea
tenuiflora
Sisymbrium
TABLE V.
(CONTINUED)„
(I & 2)
No. Feeding Sitesi
8
cy/fr/cv
Taxa
S H R U B S (cont.)
Gut-IevFez-Ia
savothvae
Rhus
tvilobata*
Saveobatus
VevnrLeuZatus
GRASSES*
(3 & 4)
14
cy/fr/cv
43/11/ 3
25/ 5/ I
13/ 2/tr
-
AGE IN WEEKS
(5 S= 6)
(7 & 8)
16
17
cy/fr/cv
cy/fr/cv
10/ 4/tr
_
-
(9 & 10)
11
cy/fr/cv
(11 & 12) (13 S= 14)
9
6
cy/fr/cv cy/fr/cv
21/ 3/ I
9/ 1/tr
13/ 3/ I
25/ 3/ I
17/ 3/tr
7/ I/ I
12/ 1/tr
-
200/99/63
100/100/74
100/99/80
100/87/69
100/99/70
13/ 5/ I
42/16/ .2
54/14/ 2
42/11/ 4
52/11/ 2
-
100/100/59 100/94/63
GRASS-LIKE:
Cavex spp .*
I/ One feeding site/collected chick equaling 20 plots.
2/ Constancy/frequency/canopy coverage.
* Indicates its use by chicks as food.
34/15/ 2
34/ 4/tr
TABLE X.
VEGETATIVE MEASUREMENTS TAKEN AT SAGE GROUSE BROOD SITES IN 1966 AND 1968.
Month
Year
No. of Transects
Taxa
Junel/
(1966)
_______ July _____
(1968)
- (1966)
18
19
8
2/ co/fr/ca
co/fr/ca
co/fr/cal'
100/87/25 100/99/53
100/92/34
IrO R B S :
AohiVLea
32/ 4/tr 39/ 6/ I
13/ 1/tr
miVLefoiiwn
Andvosaee
15/ 4/ I 11/ 1/tr
septenbrionaUs 25/ 4/tr
Avenaria
5/ 2/tr 22/ 5/ I
hoohevi
Artemisia
75/26/ 4 • 57/18/ 4 78/31/ 7
fvigida
Artemisia
17/ 2/ I 11/ 4/ I
Ludovioiana
Aster
spp.
50/ 9/tr
10/ 1/tr
33/ 8/ 2 ’
■
_____ August_______
(1968)
(1966)
23
16
co/fr/ca co/fr/ca
100/64/16 100/95/48 100/80/36
100/84/15
67/10/ I
75/ 5/tr
19/ 4/tr
21/ 7/ I
7/.3/tr
12/ 1/tr
-
8/ 1/tr
Bahia
oppositifolia
Cqmelina
miorooarpa
Collomia
linearis
Convolvulus
arvensis
Erigeron
vumilus
Gaura
oooeinea
Grindelia
squarrosa
_
13/ 2/tr
6/.3/tr
-
-
-
-
13/ 2/tr
25/15/ 3
-
-
-
33/32/ 8
42/16/ 4
26/ 4/tr
12/ 2/ I
-
43/ 4/ I
36/ 7/ 2
-
16/ 2/tr
—
—
-
-
-
-
-
-
-
-
-
-
6/ 2/tr
—
-
37/16/ 3
Astragalus
spp.
_____ September
(1966)
(1968)
3
4
co/fr/ca
co/fr/ca
6/ 2/tr
-
56/11/ I
-
6/ 1/tr
-
22/ 2/tr
-
8/ 2/tr
21/ 8/ 3
-
16/ 1/tr
6/.3/tr
10/ 1/tr
10/ 2/tr
17/ 4/tr
22/ 4/ I
8/ 1/tr
43/ 7/ I
28/12/ 2
24/ 7/ I
59/15/ 4
33/ 2/tr
—
50/23/ 5
75/ 4/ I
25/ 3/ I
TABLE X.
(CONTINUED).
Month
Year'
No. of Transects
Taxa
June
(1966)
8
co/fr/ca
July
(1968)
(1966)
18
19
co/fr/ca co/fr/ca
August
(1966)
(1968)
16
23
co/fr/ca co/fr/ca
September
(1966)
(1968)
3
4
co/fr/ca
co/fr/ca
FORBS (cont.)
Haplo-Pap-PiiS
- nuttdll-i
Hedeoma
■hispida
HeVLanthus
spp.
Hymenoxys
-aeaulus
Iva
axillaris
Laotuea
puldhella
Laetuea
sevriola
Lepidium
densiflorwn
Lepidium
perfoliatum
Medieago
lupulina
Medieago
sativa
Melilotus
officinalis
Opuntia
polyeantha
Penstemon
albidus
25/ 3/tr
“
—
—
11/ 2/tr
—
—
—
11/ 1/tr
—
.
4/ 1/tr
—
17/ 2/tr
—
6/ 1/tr
.
13/ 4/ I '
13/ 3/tr
75/11/ I
-
—
6/.3/tr
38/ 6/tr
-
"
"
"
6/.3/tr
—
6/.3/tr
12/ 3/ I
15/ 3/tr
34/ 3/tr
18/ 3/ I
38/15/ 4
-
67/33/ 5
30/ 3/tr
20/ 5/ I
-
—
6/ 4/ 2
6/.3/tr
-
-
—1
—
25/ 4/tr
5/.3/tr
-
"
6/.3/tr
50/32/13
38/ 6/ I
-
‘
13/ 7/ 5
33/32/31
72/43/22
44/20/ 3
90/49/22
33/ 2/ I
50/ 8/ 2
—
17/ 4/ I
32/ 3/tr
12/ 2/tr
33/ 2/tr
50/ 9/ I
-
6/ 1/tr
62/26/ 8
-
-
-
-
TABLE X.
(CONTINUED).
Month
Year
No. of Transects
Taxa
FORBS (cont.)
Phlox
hoodi-i
Plantago
spp.
Polygomm
avioulan
Polygonum
' ■douglasii
Psovalea
■Tenulflova
RaTlblda
■oolumnlfeva
Salsola
■- kail
Slsymbvlum
spp.
Solldago
mlssouvlensls
Solldago
mollis
Symphovlqavpos
spp.
Sphaevaleea
.eoeelnae
Tavaxaeum
officinale
Thlaspl
avvense
June
July
( 196 6)
(1966)
(1968)
8
co/fr/ca
19
•co/fr/ca
18
co/fr/ca
50/8/ I
14/ 7/ I
63/16/ I
37/ 3/tr
August
(1966)
(1968)
16
co/fr/ca
23
co/fr/ca
September
(1966)
(1968)
3
co/fr/ca
4
co/fr/ca
67/12/tr
75/23/ I
3/ 1/tr
61/39/ 3
51/ 9/ I
31/ 5/tr
6/.3/tr
6/ 3/tr
29/ 3/ I
10/ 1/tr
17/ 2/ I
-
15/ 4/ I
17/ 3/ I
18/ I/ I
6/.3/tr
-
-
-
27/ 7/ 2
28/ 3/ I
12/ 1/tr
16/ 1/tr
-
-
-
-
-
-
-
-
25/ 8/ I
7/.3/tr
-
-
-
-
17/ 2/tr
6/.3/tr
6/.3/tr
-
_
-
25/ 8/tr
__
9/ 1/tr
4/.3/tr
.
—'
-
-
4/ 1/tr
63/12/tr
68/11/ I
72/15/ I
24/ 5/ I
29/ 5/ I
33/ 8/tr
50/ 5/ I
50/ 8/ I
41/28/10
89/35/ 8
20/ 7/ 2
75/26/ 4 100/23/ 9
75/29/ 3
25/11/ I
11/ 1/tr
6/ 3/tr
-
17/ 2/tr
-
-
TABLE X.
(CONTINUED).
Month
Year
No. of Transects
Taxa
FORBS (cont.)
Thelas-perma
marginatum
Tragopogon
diibius
Verbena
braeteata
Vioia
americana
Xanthium
strumarium
Unknown Forbs
SHRUBS:
Artemisia
oana
Artemisia
tridentata
Chrysothamnus
nauseosus
Gutierrezia
sarothrae
Saroobatus
vermioulatus
Unknown Shrubs
June
(1966)
8
co/fr/ca
38/ 3/ I
- July
August
v (1966)
(1968)______ (1966)
(1968)
19
co/fr/ca
18
co/fr/ca
5/.3/tr
6/.3/tr
51/ 7/ I
61/ 9/ I
-
11/ 1/tr
September
(1966)______ (1968)
16
co/fr/ca
23
co/fr/ca
19/ 2/tr
42/ 5/ I
-
16/ 2/tr
-
-
3
co/fr/ca
4
co/fr/ca
25/ 1/tr
-
57/ 7/ I
78/25/ 3
19/ 2/tr
35/ 5/ I
75/10/ I
62/44/ 4
44/ 6/ I
44/ 6/ 2
13/ 1/tr
17/ 2/tr
33/ 2/tr
25/ 3/tr
88/21/ 7
78/24/ 8
83/28/27
76/21 2
56/20/ 6
67/42/19
100/53/14
25/10/ 3
16/ 3/ I
17/ 4/ I
12/ 2/ I
8/ 1/tr
50/ 9/ 3
56/16/ 6
72/20/ 7
58/14/ I
36/10/ 4
33/27/14
75/41/12
13/ 1/tr
5/.3/tr
6/ 1/tr
31/ 6/ I
39/ 6/ 2
27/ 4/tr
23/ 4/ I
33/10/ I
50/ 8/ I
24/ 3/tr
6/.3/tr
15/ 2/ I
63/23/ 3
-
-
25/ 3/ I
-
-
-
33/ 2/tr
33/ 12/ 5
-
-
-
—
50/ 6/ I
TABLE X.
(CONTINUED).
Month
Year
No. of Transects
Taxa
GRASSES:
GRASS-LIKE:
Carex spp.
June
(1966)
8
co/fr/ca
100/96/74
38/ 9/ I
. -,..... July
(1966)
(1968)
'19
co/fr/ca
18
co/fr/ca
100/97/75 100/99/69
73/15/ 3
39/15/ 2
August
(1968)
- (1966)
16
co/fr/ca
23
co/fr/ca
September
(1966)
(1968)
3
co/fr/ca
100/93/62 100/97/64 100/100/63
44/21/ 2
I/ No Daubemire transects were completed ,during June, 1968.
2j co/fr/ca = constancy/frequency/Canopy coverage.
12/ 2/tr
33/20/ 4
4
co/fr/ca
100/96/67
50/11/ 2
LITERATURE CITED
Batterson, W. M . , and W. B . Morse.
1948.
Game Comm.
Fauna Series.
1:1-29.
Oregon sage grouse.
Oregon
Booth, W. E.
1950. Flora of Montana. . Part I , Conifers and Monocots.
Research Foundation, Montana State College, Bozeman.
232 pp.
_____ , and J . C. Wright.
1959. Flora of Montana. Part II, Dicoty­
ledons . Research Foundation, Montana State College, Bozeman.
250 p p .
Canfield, R. H.
1941. Application of the line interception method in
sampling range vegetation. J . Forestry.
39(4):388-394.
Daubenmire4 R. 1959. A canopy-coverage method of vegetational analysis
Northwest Sci.
33(1):43-64.
Eng, R. L.
1955. Wildlife Investigations. Montana Fish and Game Dept.
Job Compl. Rept., Project W-74-R-1, Job 3.1. 6 pp.
Gieseker, L. F.
1938.
Soils of Petroleum County.
Expt. Sta. Bull. 363.
46 pp.
Montana Agri.
1939. A study of the sage grouse (Centroeereus vrophasianus)> with special reference to life history, habitat re­
Griner, L. A.
quirements, and numbers and distribution.
State Agri. Coll., Logan.
83 pp.
M. S . Thesis.
Utah
Klebenow, D. A. and G. M. Gray.
1967. Food habits of juvenile sage
grouse. Proc. 20th Am., Soc. Range M gmt. pp. 80-83.
Martin, A. C., R. H. Gensch and C . P. Brown.
1946. Alternative methods
in upland game bird food analysis. J. Wildl. Mgmt. 10(1):8-12.
Martin, N. S . 1965. Effects of sagebrush manipulation on sage grouse.
M. S . Thesis. Montana State College, Bozeman.• 38 pp.
PattersQn, R. L.
1952,
Denver.
341 pp.
The sage grouse in Wyoming.
Pyrah, D. B.
1963.
Sage grouse investigations.
Dept,, Job CompI . Rept., Project W-125-R-2.
Sage Books, Inc.,
Idaho Fish and Game
71 p p . .
-39Rasmussen, D. I. and L. A. Griner. 1938. Life history and management
studies of the sage grouse in Utah, with special reference to
nesting and feeding habits.
Trans. N. Am. Wildl. Conf. 3:852-864.
U. S. Department of Commerce,
69(6-9):109-203.
_____ 1968.
1966.
Climatological data Montana.
Climatological data Montana.
71(6-9) :109-209.
vv,0781 8
N378
P443
cop.2
Peterson, Joel Gordon
The food habits and
distribution of
^^^^juvenile sage grouse in
central Montana
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