EMSL-LV-539-6                                             EMSL-LV-539-6
            FOOD HABITS AND RADIONUCLIDE TISSUE CONCENTRATIONS
                 OF NEVADA DESERT BIGHORN SHEEP 1972-1973
           Monitoring Systems Research and Development Division
             Environmental Monitoring and Support Laboratory
                  U.S. ENVIRONMENTAL PROTECTION AGENCY
                          Las Vegas, NV  89114
                            Published  June  1976
              This study performed under a Memorandum
                 of Understanding No. AT(26-l)-539
                            for the
         U.S. ENERGY RESEARCH AND DEVELOPMENT ADMINISTRATION

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EMSL-LV-539-6
EMSL-LV-539-6
            FOOD HABITS AND RADIONUCLIDE TISSUE CONCENTRATIONS
                 OF NEVADA DESERT BIGHORN SHEEP 1972-1973
                                   by               '     *
               K. W. Brown, D. D. Smith, D.  E.  Bernhardt,
                     K. R. Giles, and J. B.  Helvie**
          Monitoring Systems Research and Development Division
            Environmental Monitoring and Support Laboratory
                 U.S. ENVIRONMENTAL PROTECTION  AGENCY
                         Las Vegas, NV  89114
                          Published June 1976
                 This study performed under a Memorandum
                    of Understanding No. AT(26-l)-539
                               for the
            U.S. ENERGY RESEARCH AND DEVELOPMENT ADMINISTRATION
   Mr.  Bernhardt is Chief, Artificial  Radioactivity Section, Office of
  Radiation Programs, Las Vegas Facility.
    Mr.  Helvie is Refuge Manager of the Sacramento National Wildlife
  Refuge,  U.S. Fish and Wildlife Services, Rt. 1, Box 311, Willows,
  CA  95988.

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Effective June 29, 1975, the National Environmental  Research Center-
Las Vegas (NERC-LV) was designated the Environmental Monitoring and
Support Laboratory-Las Vegas (EMSL-LV).  This Laboratory is one of
three Environmental Monitoring and Support Laboratories of the
Office on Monitoring and Technical Support in the U.S. Environmental
Protection Agency's Office of Research and Development.

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FOOD HABITS AND RADIONUCLIDE TISSUE CONCENTRATIONS OF NEVADA DESERT
BIGHORN SHEEP 1972-1973*
 Kenneth W. Brown, Donald D. Smith,
 David E. Bernhardt, and Kenneth R. Giles
 U.S. Environmental Protection Agency
 Environmental Monitoring and Support Laboratory
 P. 0. Box 15027
 Las Vegas, Nevada  89114
 Jack B. Helvie
 Sacramento National Wildlife Regure
 U.S. Fish and Wildlife Services
 Rt. 1, Box 311
 Willows, CA  95988
Abstract:  The botanical composition of the diet and radionuclide
content of selected tissues of desert bighron sheep (Ovis canadensis
nelsoni) collected during the 1972 and 1973 hunting seasons were
determined by analyzing rumen contents, and lung, liver, kidney,
and bone tissues.
Botanical examination of the rumen contents showed that grass
exceeded 50% of the diet of 10 of 14 animals collected in 1972
and 12 of 18 animals collected in 1973.  Desert needlegrass (Stipa
speciosa), Indian rice grass (Oryzopsis hymenoides), and squirrel
tail (Sitanion hystrix) were the major grasses utilized.  The
dominant shrub species consumed included the joint firs (Ephedra
viridis) and (Ephedra nevadensis), Mohave yucca (Yucca schidigera),
and cliff rose (Cowania mexicana).
*
 Presented at the 19th Annual Meeting of the Desert Bighorn Council,
April 9-11, 1975, Indio, California.

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With the exception of potassium-40, gamma-emitting radionuclides
were not detected in desert bighorn sheep tissue.  The tritium
levels reported were within environmental levels.  Strontium-90
levels averaged 4.9 and 4.1 pCi/gram of bone ash for 1972 and
1973, respectively, continuing the downward trend observed in
recent years.  Uranium levels were similar to those reported from
cattle grazing the same general geographic areas.  The daily con-
sumption for one year of 500 grams of liver containing the highest
levels of plutonium and uranium would result in a dose to the human
bone, the tissue expected to receive the highest dose, of approxi-
mately 1 mrem/year.  This is less than 1% of the radiation
protection guides for the general population.

                           INTRODUCTION

The  U.S. Fish and Wildlife Service of the U.S. Department of
Interior and the Environmental Monitoring and Support Laboratory-
Las  Vegas (EMSL-LV) of the U.S. Environmental Protection Agency
have in past years initiated and cooperated in many investigations
concerning the desert bighorn sheep (Ovis canadensis nelsoni).  The
information and data obtained from these cooperative studies such as
reported by Helvie and Smith (1970), Kramp (1965), and Cohen (1968),
have contributed not only to a greater understanding of this animal's
behavior, but also to better management practices.

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 Investigations  to  determine  radionuclide  concentrations  in various
 tissues  of  wildlife  species  have  been  conducted  for many years by
 the  Animal  Investigation  Program  (AIP)  of EMSL-LV.  This program
 was  established in 1957 by the  U.S. Atomic  Energy Commission  (AEC).
 (Recently renamed  the  Energy Research  and Development Administra-
 tion,  ERDA).  The  program assesses fission  and activation products
 in biological samples, maintains  veterinary relations with off-site
 populations, and investigates alleged  damage to  domestic animals
 from the ERDA testing  activities.

 During the  past few years, a number of  studies have been conducted
 in Nevada in areas inhabited by desert  bighorn sheep.  These  investi-
 gations  have been  conducted  in  both southern Nevada and central
 Nevada.  The emphasis  has been  either on  habitat analysis or  vege-
 tative surveys  and, in some  cases, food habit analyses.  A few
 reports  have been  published  concerning  radionuclide concentration
 in selected tissues of big game animals in  the southern Nevada area.

 The  data from most of  these  reports have  been incorporated into a
 soon to  be published book entitled, The Desert Bighorn, Its Life,
 History, Ecology, and Management, edited  by Lowell Sumner and
Gale Monson (1971).  Other data, which will be extremely useful
to investigators, include bighorn habitat evaluations by Ferrier
and Bradley (1971) and Breyen (1971), and the floras of the Virgin
and the McCullough Mountains by Armstrong  (1969) and Bostick  (1973).

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Most of the data dealing with radionuclide concentrations in desert
bighorn sheep have been reported in AIP annual progress reports.
Some additional data have been published in Desert Bighorn Council
Transactions.  These papers were authored by Smith (1971), Kramp
(1965), and Fountain (1962).
In 1972, a cooperative  study between the two Federal  agencies
mentioned and the Nevada Fish and Game Commission was initiated to
identify species composition of vegetation in the rumen ingesta of
desert bighorn sheep and to determine the radioactive concentration
in selected tissues.  The data presented in this report are from
animals collected during the 1972 hunt from November 16 to
December 17, and from the 1973 hunt from November 17 to December 16.

The authors are indebted to personnel of the Region III Headquarters
of the Nevada Department of Fish and Game for disseminating sample
collection kits and receiving samples from participating hunters.
The cooperation of these sportsmen in collecting samples from their
kills made this study possible.

                               METHODS

Prior to the 1972 and 1973 hunting seasons, hunters were given an
indoctrination course which emphasized the identification of
legally harvestable rams.  During this course, each hunter was
requested, on a voluntary basis, to collect the following tissues,

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lung, liver, kidney, and bone, and to collect a sample of
rumen ingesta.

The samples were delivered to EMSL-LV for radionuclide and food
habit analyses.  All samples except the bone were analyzed for
gamma-emitting radionuclides on a 4- by 4-inch Nal(Tl) crystal at-
tached to a 400-channel pulse height analyzer.  Kidney samples were
analyzed for tritium using the method described previously by
Moghissi trt al_.  (1973).

The samples for  strontium, plutonium, and uranium analyses were
prepared by dry  ashing.  Plutonium and uranium were analyzed by
alpha spectroscopy  (Talvitie, 1971 and 1972).  Other radionuclide
analytical procedures used at the NERC-LV are described by
Johns (1970).

The botanical analysis of the rumen ingesta was accomplished by
examining a random aliquot of the ingesta with a binocular micro-
scope.  The sample was washed on a fine mesh screen preparatory
to examination.  After the species in the sample were identified,
a visual estimate of the percentage of each species was made and
recorded (Leach, 1956).  No effort was made to determine the
radionuclide content of individual species found in the rumen
ingesta.

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The browse and forb species were identified according to Munz (1965)
and grasses according to Hitchcock (1950).

In 1972, the tissues and rumen ingesta from 14 animals were analyzed.
All were harvested in southern Nevada with eight collected on the
Desert National Wildlife Range, two from the Meadow Valley Range,
two from the Muddy Mountain area, and one each from the McCullough
Mountains and the Eldorado Mountains.  These rams ranged from
4  to 11 years of age.

 In 1973,  18 animals were sampled.  Similar to the 1972  hunt, most
 of these  animals were collected in southern Nevada with 10 coming
 from  the  Desert National Wildlife Range.  Of the remaining eight
 animals,  three were  collected  in the Muddy Mountains-Boulder Wash
 area,  two from the  Eldorado Mountains, one from the Meadow Valley
 Range area, one from the Highland Range, and one from central Nevada
 near  the  Lone Mountain  in  Esmeralda County.  These rams ranged from
 4 to  10 years of age.

                       RESULTS  AND DISCUSSION
 Food  Habits Analysis
 The animals collected on the  Desert  National Wildlife Range  will  be
 discussed and  presented as a  single  grouping, because of  their
 geographical  relationship.  The data  from  the remaining animals,
 except the ram harvested in Esmeralda  County during  the 1973 hunt,
 will  be composited  and  presented  as  another separate group.   The

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compositing of data from the latter group was done because of the
small sample size collected from any specific geographical area.

 Tables  1  and  2  show the  botanical  composition of  forage utilized by
 desert  bighorn  sheep collected  on  the  Desert National Wildlife Range
 in 1972 and 1973,  respectively.  The data  show that  in 1972  grasses
 exceeded 70%  of the diet of five of the  eight animals collected,
 with two having less than 15% and  40%.   Browse species contributed
 an average of 40% composition,  with animals  No. 1 -and No.  4  having
 in excess of  85%.   The forbs in the rumen  contents of these  eight
 animals averaged less than 1.0%.   However, wild buckwheat
 (Eriogonum spp.) was present in 75% of the desert bighorn sheep
 collected.   Identified grasses  included  blue grass  (Poa spp.) and
 desert  needlegrass (Stipa speciosa) which  contributed an  average
 of 2.4% and 1.0%,  respectively,  to the diet  of these animals while
 unidentified  grasses constituted 53.2% of  the diet.  Cliff rose
 (Cowania mexicana), the  joint firs (Ephedra  vicidis) and  (Ephedra
 nevadensis),  and big sagebush (Artemisia tridentata) were the major
 browse  species  consumed, contributing  12.8%, 10.6%,  9.8%, and 5.9%
 of the  diet,  respectively.

 In 1973, the  type of vegetation consumed by  the ten  animals  col-
 lected  on the Desert National Wildlife Range was  comparable  to
 that utilized by the eight animals collected in  1972.   Grasses

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                                                                8
made up slightly more than 50% of the diet with browse species con-
tributing 45%.  Forb species consumption increased over 1972 with
the spurge (Euphorbia spp.) and other unidentified species con-
tributing over half of the forbs utilized.  A total of seven grasses
were identified in the ingesta with four of these contributing an
average of 39.4% of the diet.  The frequency of occurrence of these
four species in the rumen was 80% for Stipa specidsa, 70% for
Indian rice grass (Oryzopsis hymenoides), 50% for squirrel tail
(Sitanion hystrix), and 60% for Hilaria jamesii.   The major dif-
ference in browse species utilized between the two years was the
presence of the Mohave yucca (Yucca schidigera).   This species}
which was absent in 1972, contributed over 17.0%  of the diet and
occurred in 70% of the animals in 1973.  Other important browse
species  included Ephedra viridis, Cowania mexicana, four-winged
saltbush  (Atriplex canescens), and Artemisia tridentata.

Tables  3 and  4 show the  average botanical composition and frequency
of occurrence of plant species eaten by the second group of animals
harvested  in  southern  Nevada from areas other than the Desert
National  Wildlife  Range  during the 1972 and 1973 hunting seasons.
Grasses were  the  dominant  type of vegetation by composition found
in these animals with  73%  in 1972 and  72% in 1973.  Forbs exceeded
 13% of the diet  in  the 1973  animals with  Euphorbia spp. accounting
for 7.8% of this  total.  The amount  of forbs in the ingesta of  the
 1972 animals, 1.2% (Table  3),  and  that consumed by the  1973 animals,

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harvested on the Desert National Wildlife Range, 0.7% (Table 1),
are comparable.  The occurrence of browse species for both groups
was approximately the same with Ephedra viridis heading the list
followed by CoWam'a mexicana, Ephedra nevadensis. and Artemisia
tridentata.  Yucca schidigera was present in both groups of 1973
animals (Tables 2 and 4); however, the difference is quite signi-
ficant.  An explanation for this difference is difficult as
Yucca schidigera is commonly found in all the bighorn habitats.  The
preferred grasses were approximately the same as those found in
the animals collected on the Desert National Wildlife Range, with
Oryzopsis hvmenoides. Stipa speciosa. Sitanion hystrix, and
Hi!aria jamesii being dominant.

The single ram harvested on the Lone Mountain in Esmeralda County
had nearly 100% grass in its rumen.  There was only a trace amount
of Eriogonium spp. in the ingesta and no browse species.  The
preferred grasses included Stipa speciosa followed by Sitanion
hystrix, and giant wild rye (Elymus cinereus).  The data obtained
from this animal substantiated the work done by Yoakum  (1964).
He concluded that grasses were the preferred food during the fall
and winter months in this area.

The results of the food habit analysis from all these animals which
were collected in a variety of geographical areas in southern
Nevada, support previous investigations by Barrett (1964),

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                                                              10
Yoakum (1966), and Browning (1971).   They reported that grasses
made up more than 50% of the diet of animals collected on the
Desert National Wildlife Range, the  Meadow Valley Range,  and near
the Potosi Mountain.

Radionuclide Content of Selected Tissues
The radionuclide data for each tissue from each  animal  sampled
during 1972 and 1973 are presented in the AIP annual  reports
authored by Smith Łt aJL (1975 a, b).  These data are summarized
in Tables 5 and 6 and in the following discussion.   The data are
                                      12
expressed as pCi or fCi.  A pCi is 10    Curies  and a fCi is
10    Curies.  The Curie is a group  of units indicating 3.7x10
disintegrations per second or the disintegration rate of one gram
of radium.

Other than the naturally occurring potassium-40, gamma-emitting
radionuclides did not exceed minimum detectable activities  (MDA)
in any of the tissues sampled during 1972 or 1973.  The rumen
contents occasionally contained detectable levels of zirconium-95,
ruthenium-103, cesium-137, and cerium-141.

Tritium levels in the aqueous portion of the kidneys during 1972
ranged from 260 to 1,800 pCi/liter (median value 355 pCi/liter)
while the 1973 levels ranged from 240 to 730 pCi/liter (median
value of 390 pCi/liter).  These values are considered to be within

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                                                               11
environmental limits as the water from Lake Mead in 1973 averaged
890 pCi/liter (range of 640 to 1,300 pCi/liter) as reported by
the Monitoring Operations Division of EMSL-LV  (1974).
The average strontium-90 content in the 1972 bones was 4.9 pCi/gram
of ash and 4.1 pCi/gram of ash in the 1973 samples.  This continues
the downward trend observed in recent years; e.g., the average for
1971 was  5.8 pCi/gram of ash.

As reflected in Tables 5 and 6, bone (hock) was the only tissue
sampled during both years in sufficient numbers to allow meaningful
comparison of actinide values.  The actinide levels in desert
bighorn sheep are generally of the same magnitude as reported in
cattle from similar areas.   Uranium values were higher in animals
collected in southern Nevada than in animals from the Desert
National  Wildlife Range.  This was also found in a 1972 study with
cattle from an area near Searchlight, Nevada, and from the Nevada
Test Site (Smith e_fc ajk  1976).  This probably reflects the levels
of naturally occurring uranium present in the soils of the two
areas (Garside 1973).

Human dose estimates, for assumed ingestion of the liver from
bighorn sheep, are given in Table 7.  The estimates are for human
bone, based on postulated consumption of 500 grams of liver per day
from the animal  containing the highest measured concentrations of

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                                                               12
plutonium and uranium.   The concentrations of radionuclides, in pCi
per kilogram of wet tissue versus gram of ash, are taken from the
tabulation by Smith et_ al_. (1975 a, b).
The dose calculation parameters are based on the data and assump-
tions of the International Commission on Radiological Protection
(1959, 1968).  Details  concerning the calculations of the dose
conversion parameters are given by Smith e_t aj_.  (1976).

The total dose committment to the bone, accrued  over a 50-year
period after ingestion  for one year, is 7 mrem.    The total dose
rate at the end of one  year's ingestion (not given in Table 7) is
about 1 mrem/year.  This is less than 1% of the  radiation
protection guides of the National Council on Radiation Protection
and Measurements  (1971) for a sample of the general population.

It is obvious from these calculations that the consumption of the
flesh of these animals would pose little hazard  to the public.
Insufficient data are available to draw any conclusions on possible
radiation effects on the desert bighorn sheep.  However, detrimental
or deleterious effects  have not been observed in domestic animals
whose tissues contained similar levels of radionuclides.  Moreover,
pathological lesions have not been found at necropsy that could be
attributed to ionizing  radiation.
 —.
  The mrem is 0.001 rem, a radiation dosimetry quantity that
 considers energy absorption and biological effectiveness.

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                                                               13
                          LITERATURE CITED
Armstrong, J. D., 1969.  Vegetation of the Virgin Mountains, Clark
     County, Nevada.  A thesis.  University of Nevada, Las Vegas.
     106 pp.

Barrett, R. H., 1964.  Seasonal Food Habits of the Bighorn at the
     Desert Game Range, Nevada.  Desert Bighorn Council Trans-
     actions (8) pp. 85-93.

Bostick, V. B., 1973.  Vegetation of the McCullough Mountains,
     Clark County, Nevada.  A thesis.  University of Nevada, Las
     Vegas.  232 pp.

Breyen, L. J., 1971.  Desert Bighorn Habitat Evaluation in the
     Eldorado Mountains of Southern Nevada.  A thesis.  University
     of Nevada, Las Vegas.  96 pp.

Browning, B. M., 1972.  The Desert Bighorn, Its Life History,
     Ecology and Management.  Edited for the Desert Bighorn
     Council by Lowell Sumner and Gale Monson.  Chapter 4.  Food.
     (Preprint).

Cohen, S. L., 1968.  Amputation of the Forelimb of a Desert
     Bighorn Sheep.  Desert Bighorn Council Transactions (12)
     pp. 28-39.

The Desert Bighorn, Its Life History, Ecology and Management.
     Edited for the Desert Bighorn Council by Lowell Sumner
     and Gale Monson.  1971.  (In review).

Ferrier, G. J. and W. G. Bradley, 1970.  Bighorn Habitat in the
     Highland Range.  Desert Bighorn Council Transactions (14)
     pp. 66-93.

Fountain, E. L., 1962.  Nuclear Test Program as It is Related to
     the Desert Bighorn Sheep.  Desert Bighorn Council Trans-
     actions (6) pp. 62-67.

Garside, L. J., 1973.  Radioactive Mineral Occurrences in Nevada.
     Nevada Bureau of Mines and Geology.  University of Nevada, Reno.
     Bulletin 81.  121 pp.


 Helvie, J. B. and D. D. Smith, 1970.  Summary of Necropsy Findings
      in Desert Bighorn Sheep.  Desert Bighorn Council Trans-
      actions (14) pp. 28-42.

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                                                               14


Hitchcock, A. S., 1950.  Manual of the Grasses of the United
     States.  U.S. Department of Agriculture Misc. Publ. 200,
     1051 pp.  U.S. Government Printing Office, Washington, DC.

International Commission on Radiological  Protection,  1959.   Report
     of Committee II  on Permissible Dose for Internal Radiation,
     Report 2.

International Commission on Radiological  Protection,  1968.   Evalu-
     ation of Radiation Doses to Body Tissues from Internal
     Contamination Due to Occupational  Exposure, Report 10.

Johns, F. B., 1970.  Southwestern Radiological  Health Laboratory
     Handbook of Radiochemical  Analytical  Methods.  SWRHL-11.
     Southwestern Radiological  Health Laboratory, Las Vegas,
     Nevada.  122 pp.
                                           90
Kramp, R. C., 1965.  Preliminary Report on   Sr Levels in Hock
     Joints of Desert Bighorn Sheep and Mule Deer.  Desert Bighorn
     Council Transactions (9) pp. 87-92.

Leach, H. R., 1956.  Food Habits of the Great Basin Deer Herds of
     California.  California Fish and Game No.  4.  Vol. 42.
     pp. 243-308.

Moghissi, A. A., E. W. Bretthauer, and E.  H. Compton, 1973.
     Separation of Water from Biological  and Environmental  Samples
     for Tritium Analysis.  Analytical  Chem.  Vol. 45.
     pp. 1565-1566.

Monitoring Operations Laboratory, 1974.  Environmental Monitoring
     Report for the Nevada Test Site and Other Test Areas Used
     for Underground Nuclear Detonations.   NERC-LV-539-31.
     National Environmental Research Center-Las Vegas, Las Vegas,
     Nevada.  106 pp.

Munz, P. A. and D. D. Keck, 1965.  A California Flora.  University
     of California Press.  Berkeley and Los Angeles.

National Council on Radiation Protection and Measurements, 1971.
     Basic Radiation Protection Criteria.   NCRP Report No.  39.

Smith, D. D., 1971.  Radiation  Surveillance of Ruminants On and
     About the Nevada Test Site.  Desert Bighorn Council Trans-
     actions (15) pp. 101-108.

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                                                               15
 Smith,  D.  D.,  S.  C.  Black,  D.  E.  Bernhardt,  R.  R.  Kinnison,  and
      K.  R.  Giles,  1976.   Tissue  Burdens  of Selected  Radionuclides
      in  Beef Cattle  On  and  Around the  Nevada Test  Site.   NERC-LV-
      539-29.   National  Environmental Research Center-Las  Vegas,
      Las  Vegas,  Nevada.   84 pp.

 Smith, D. D.,  K. R. Giles,  and D.  E. Bernhardt, 1975a.  Animal
      Investigation Program  1972 Annual Report.  NERC-LV-539-35.
      National  Environmental  Research Center-Las Vegas, Las Vegas,
      Nevada.   82 pp.  (in press)

	, 1975b.  Animal  Investigation Program 1973 Annual
      Report.   National Environmental Research Center-Las Vegas,
      Las Vegas, Nevada,   (in preparation)
 Talvitie,  N.  A.,  1971.   Radiochemical  Determination  of  Plutonium  in
      Environmental  and  Biological  Samples  by  Ion  Exchange.   Western
      Environmental  Research  Laboratory,  Las Vegas, Nevada.
      Analytical Chemistry, Vol.  43,  pp.  1827-1830.

 	,  1972.   Electrodeposition of  Actinides  for Alpha
      Spectrometric  Determination.  Western Environmental  Research
      Laboratory,  Las  Vegas,  Nevada.  Analytical Chemistry,  Vol. 44,
      pp. 280-283.

 Yoakum, J.,  1964.   Bighorn Food  Habits - Range  Relationships in the
      Silver  Peak  Range,  Nevada.   Desert  Bighorn Council  Trans-
      actions  (8)  pp.  95-102.

 	,  1966.   Comparison  of Mule  Deer  and  Desert Bighorn
      Seasonal  Food  Habits.   Desert Bighorn Council Transactions  (10)
      pp. 65-70.

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                                            Table 1

                  Botanical Composition by Percent of Forage  Eaten  by  Bighorn
               Sheep Collected on the Desert National  Wildlife  Range,  Nevada-1972


                                              Animal                     Av. Compo-
Species                    1     2     3     45      6      7     8  sition (%)   Frequency  (%)
Other  (unidentified)      O6770TOTO  3370  S570   TO   71.0      53.2          100
Poa_ spp.                  0.0   0.0   0.0   0.0   7.0   0.0   2.0   10.0      2.4           37
Stipa  speciosa            0.0   7.0   0.0   0.0   0.0   0.0   0.0    0.0      1.0           12
Hi!aria jamesii           1.0   5.0   0.0   0.0   0.0   0.0   0.0    0.0      0.7           25
Festuca spp.              0.0   0.0   0.0   2.0   0.0   0.0   0.0    3.0      0.6           25
Stipa  spp.                0.0   0.0   0.0   0.0   0.0   4.0   0.0    0.0      0.5           12
Oryzopsis hymenoides      0.0   0.0   1.0   0.0   0.0   2.0   0.0    0.0      0.3           25
Bromus tectorium0.0   0.0    T    0.0   0.0   0.0   0.0    0.0        T            12
            Total grass   7.0  79.0  75.0  12.0  40.0  95.0   78.0   84.0      58.7
Other  (unidentified)       T    0.0   0.0   1.0   2.0   1.0   0.0    0.0      0.5           50
Eriogonum spp..            0.0   1.0    T    0.0   1.0    T      T     T      0.2           75
Chaenactis spp.           0.0    T    0.0   0.0   0.0    T    0.0    0.0        T            25
Phacelia spp.             0.0   0.0   0.0   0.0   0.0   0.0     T     0.0        T            12
            Total forbs    T    1.0    T    1.0   3.0   1.0     T     T      0.7
Cowania mexicana         89.0   1.0   1.0   0.0   0.0   1.0   9.0    1.0      12.8           75
Ephedra vTridis           0.0   0.0   0.0  84.0   0.0   0.0   0.0    0.0      10.6           12
Ephedra nevadensis        0.0   2.0  20.0   0.0  54.0   1.0   6.0    1.0      9.8           62
ArtemisiFtridentata      4.0  15.0   2.0   0.0   0.0    T    12.0   14.0      5.9           75
Other  (unidentified)      0.0   2.0   2.0   0.0   3.0   1.0   1.0    0.0      1.1           62
Cercocarpus  intricatus    0.0   0.0   0.0   2.0   0.0   1.0   0.0    0.0      0.3           25
Ceanothus g'reggii         0.0   0.0   0.0   1.0   0.0   0.0   0.0    0.0      0.1           12
Pinus monophylla          0.0   0.0   0.0    T    0.0   0.0   0.0    0.0        T            12
            iota I shrubs 93.0  20.0  25.0  87.0  57.0   4.0   22.0   16.0      40.6
    trace

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                                             Table 2

                   Botanical  Composition by Percent of Forage Eaten by Bighorn
               Sheep Collected on the Desert National  Wildlife Range,  Nevada-!973
  ecies
     ^ speclosa
Oryzopsis hymenoides
Sitanion hystrix
Other (unidentified)
Hi!aria jamesii
Stipa spp.
Elymus cinereus
Bromus tectorium
1
b.O
9.0
17.0
0.0
0.0
0.0
0.0
0.0
2
b.
20.
0.
18.
0.
0.
0.
0.

0
0
0
0
0
0
0
0
3
ly.o
0.0
0.0
9.0
6.0
0.0
0.0
0.0
4
10.0
0.0
0.0
26.0
4.0
14.0
0.0
0.0
Animal
5 6
34.0
13.0
0.0
0.0
0.0
0.0
0.0
0.0
0.
13.
0.
15.
0.
0.
6.
0.
0
0
0
0
0
0
0
0
7
0.0
36.0
26.0
0.0
19.0
0.0
0.0
0.0
8
24.0
0.0
16.0
0.0
17.0
0.0
0.0
2.0
9
21.0
6.0
15.0
3.0
6.0
0.0
0.0
0.0
10
19.0
6.0
21.0
14.0
4.0
0.0
0.0
0.0
Ay
si
  Compo
tion
13
10
 9
 8
 5
 1.4
 0.6
 0.2
50.1
Frequency
     80
     70
     50
     60
     60
     10
     10
     10
Other (unidentified)
Euphorbia spp.
Sphaeralcea spp.
Eriogonum spp.
Erodi um~c"i cutari urn
Linum lewisii
Astragalus spp.
           Total forbs
2.0
0.0
0.0
0.0
0.0
0.0
0.0
2.0
2.0
0.0
0.0
T
0.0
0.0
0.0
2.0
4.0
0.0
0.0
1.0
0.0
0.0
0.0
5.0
0.
0.
0.
0.
0.
0.
0.
0.
0
0
0
0
0
0
0
0
0.0
3.0
2.0
0.0
3.0
0.0
0.0
8.0
8.0
0.0
0.0
0.0
0.0
0.0
0.0
8.0
0.0
3.0
0.0
3.0
0.0
0.0
0.0
6.0
0.0
0.0
0.0
0.0
0.0
o.o.
0.0
0.0
0.
4.
4.
0.
0.
3.
0.
11.
0
0
0
0
0
0
0
0
0.0
0.0
0.0
0.0
0.0
0.0
T
T
 1.6
 1.0
 0.6
 0.4
 0.3
 0.3
  T
 4.2
     40
     30
     20
     30
     10
     10
     10

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                                               Table 2 (contd)

                    Botanical Composition by Percent of Forage  Eaten  by  Bighorn
                Sheep Collected on the Desert National  Wildlife Range, Nevada-1973
Species
Yucca schidigera
Ephedra viridis~
Cowania mexicana
Atrip!ex canescens
Artemisia tridentata
Juniperus monosperma
Cercocarpus intricatus
Other (unidentified)
Yucca brevifolia
Encelia spp.
Colegyme ramosissima
Atn'plex spp.
           Total shrubs

T = trace
1
36.0
0.0
7.0
0.0
20.0
0.0
0.0
3.0
0.0
0.0
0.0
0.0
2
32.0
0.0
16.0
0.0
0.0
0.0
4.0
0.0
0.0
0.0
0.0
2.0
3
38.0
11.0
6.0
0.0
0.0
0.0
4.0
2.0
0.0
0.0
0.0
0.0
4
0.0
17.0
6.0
0.0
2.0
1.0
9.0
0.0
8.0
0.0
3.0
0.0
Animal
5 6
4.0
12.0
19.0
6.0
4.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
28.0
14.0
0.0
0.0
0.0
0.0
9.0
4.0
0.0
0.0
3.0
0.0
7
4.0
2.0
1.0
0.0
0.0
0.0
0.0
0.0
6.0
0.0
0.0
0.0
8
0.0
2.0
1.0
28.0
2.0
0.0
0.0
8.0
0.0
0.0
0.0
0.0
9
0.0
0.0
0.0
0.0
0.0
26.0
0.0
0.0
0.0
12.0
0.0
0.0
Av. Compo-
10 sition (%}
32.0"
0.0
0.0
0.0
2.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
17.4
5.8
5.6
3.4
3.0
2.8
2.6
1.7
1.4
1.2
0.6
0.2
Frequency (%)
70
60
70
20
50
20
40
40
20
10
20
10
66.0 54.0 61.0 46.0 45.0 58.0 13.0 41.0 38.0 34.0
45.7
                                                                                                      00

-------
                              Table 3

        Botanical Composition and Frequency of Occurrence
           of Plant Species Eaten by Six Bighorn Sheep
               Collected in Southern Nevada-1972*
                                                              19
Species
Other (unidentified)
Hi!aria jamesii
Festuca spp.
Stipa speciosa
Oryzopsi s hymenoi des
Poa spp.
Hordeurn spp.
    Common Name

Galleta grass
Fescue
Desert needlegrass
Indian rice grass
Blue grass
Wild barley
                Total
                                             grass
    Average
Composition
     69.0
      1
      1
      0.
      0.
      0.
      0.2
     TO
                                ,3
                                .0
                                ,5
                                .3
                                ,2
                                     (%)
                          Frequency (%)
                              100
                               83
                               16
                               16
                               16
                               16
                               16
Eriogonum spp.
Other (unidenti fi ed)
Helianthus spp.
SphaeralZea spp.
Wild buckwheat

Sunflower
Mallow
               0.5
               0.3
               0.2
               0.2
Total forbs    1.2
                                              100
                                               16
                                               33
                                               16
Ephedra vi ri di s
Other (unidentified)
Ephedra nevadensis
Ceanothus greggn
CeanothuT spp.
Yucca spp".
Artemisia tridentata
Cowania mexicana
Cercocarpus intricutus
Coleogyne ramosissima
EncelTaTpp.
Atriplex canescens
Joint fir

Nevada joint fir
Desert ceanothus
Ceanothus
Yucca
Big sagebrush
Cliff rose
Little-leaved mahogany
Blackbrush
Encelia
Four-winged saltbush
                Total browse
              12.0
               7.3
               2.7
               1.3
               0.8
               0.6
               0
               0
               0
               0.2
                T
                T
                                               33
                                               66
                                               66
                                               33
                                               50
                                               16
                                               50
                                               33
                                               33
                                               33
                                               16
                                               33
T = trace
*Excluding the Desert National Wildlife Range

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                                                               20
                               Table 4

        Botanical  Composition and Frequency of Occurrence
          of Plant Species Eaten by Seven Bighorn Sheep
                Collected in Southern Nevada-1973*
Species
Qry^opsis
S/tipa
          hmenoi des.
Sitanion hystrix
Other (unidentified)
Elymus qinereus
Hilaria jamesij
Sporobolus spp.
   Common Name
Indian rice grass
Desert needlegrass
Squirrel tail
                       Giant wild rye
                       Galleta grass
                       Dropseed
                                   Total grass
    Average
Composition (%)
      23.4
      22.8
      13.9
       8.1
       1.4
       1.4
       0.9
      7T79-
Frequency (%)
    TOO
    100
     57
     57
     29
     29
     14
Euphorbia spp.
Other  (unidentified)
Argemone spp.
Eriogonum spp.
Erodium"cicutarium
Chaenactis spp.
Linum  lewisii
                       Spurge                     7.8
                                                  2.6
                       Poppy                      0.8
                       Wild buckwheat             0.7
                       Heron's bill               0.6
                       Pincushion                 0.6
                       Blue flax                  0.1
                                   Total forbs   TIT?
                                          71
                                          57
                                          29
                                          43
                                          29
                                          29
                                          14
Cowania mexicana
Other (unidentified)
Artemi s i a tridentata
Ephedra Viridis
Yucca schidigera
Ephedra nevadensis
Quercus gambelii
Coleogyne ramosissima
Arctostapliylos spp.
                       Cliff rose

                       Big sagebrush
                       Joint fir
                       Mohave yucca
                       Nevada joint fir
                       Gambel's oak
                       Black brush
                       Manzanita
                                   Total browse
                           5.
                           3.
                           2.
                           1
                           0.
                           0.
                           0.
                           0.
                           0.1
                          TO
         ,1
         .8
         .0
         ,4
         .9
         .9
         ,4
         ,3
     29
     71
     14
     43
     29
     14
     14
     29
     14
 Excluding the Desert National Wildlife Range

-------
                                                   Table 5

                 Surmiary of Actinide and Strontium Levels in the Ash from Selected Tissues from
             Desert Bighorn Sheep Collected on the Desert National Wildlife Range, Nevada, 1972-1973
Tissue
Bone
Liver
Lung
Year
1972
1973
1972
. .^^
1973
1972
1973
238Pu
fCi/g
# Samples
# >MDA
Range
Medi an
6
0
<0.87-<2.2
<2
8
7
0.77-45
2.4

7
5
<1. 6-790
11
1
0
<5.4
10
7
3.3-130
11
239PU
fCi/g
# Samples
# >MDA
Range
Median
6
4
<1.3-5.2
3.1
8
4
<0.41-2.6
1.6

7
7
5.4-210
83
1
18
10
6
<7. 1-190
19
234U
fCi/g
# Samples
# >MDA
Range
Median
6
6
1.2-7.7
6.4
8
8
1.8-6.4
2.85
NO SAMPLES
2
2
4.5-49
26.7
NA
6
6
5.8-140
14
235U
fCi/g
# Samples
# >MDA
Range
Median
6
1
<0.31-<0.88
<0.43
8
0
<0.28-<1.2
<0.43
COLLECTED
2
0
<2.4-<12
7.2
NA
6
1
<4.6-6.4
<1.75
238U
fCi/g
# Samples
# >MDA
Range
Median
6
6
1.1-7.3
6
8
8
1-3.9
1.8

2
2
5.5-25
15.3
NA
6
6
1.7-150
10.5
89Sr
pCi/kg
# Samples
# >MDA
Range
Median
6
0
<3.4-<4.7
<3.5
8
2
MDA
Range
Median
6
6
3.4-9.4
4.8
8
8
2.4-7.7
4.3

NA
NA
NA
NA = Not analyzed.

-------
                                                   Table 6

                 Summary of Actinide and Strontium Levels in the Ash from Selected Tissues
                     from Desert Bighorn Sheep Collected in Southern Nevada, 1972-1973*
Tissue
Bone
Liver
Lungs
Year
1972
1973
1972
1973
1972
1973
238n
Pu
. fCi/g
# Samples
# >MDA
Range
Median
5
0
<0.76-<2.9
<2.2
7
6
<1.7-77
17

1
1,800 ±310

8
7
<6. 9-1 ,000
33
?^Q
"yPu
fCi/g
# Samples
# >MDA
Range
Median
5
4
<1.3-17
2.9
7
2
<0. 62-15
<1.5

1
1
670 ± 140

8
4
<5.2-29
<14
234,
fCi/g
# Samples
# >MDA
Range
Median
5
5
4.7-16
10
7
7
1.5-16
3.8
NO SAMPLES
1
1
710 ± 78
NO SAMPLES
7
6
<12-170
46
235U
fCi/g
# Samples
# >MDA
Range
Median
5
2
<0.4-2
<0.63
7
1
<0.41-1.5
<0.49
COLLECTED
1
1
35 ± 14
COLLECTED
7
2
<2.5-10
<5
238U
fCi/g
# Samples
# >MDA
Range
Median
5
5
4.4-15
9.2
7
6
<0.91-13
2.5

1
1
610 ± 72

7
7
8.9-170
34
89Sr
pCi/kg
# Samples
# >MDA
Range
Median
5
0
<3.4-<5.2
<4
7
0
<0.83-<22
<2

NA

NA
90Sr
pCi/kg
# Samples
# >MDA
Range
Median
5
5
2.6-7.9
2.6
7
1.2-11
2.6

NA

NA
NA = Not analyzed.
^Excluding the Desert National Wildlife Range

-------
                                                    23


                       Table 7
Estimated Human Bone Doses from Ingestion of Liver
       Dose Accrued Over 50-Year Period After
     Ingestion of 500 Grams per Day for 1 Year
Nuclide
238Pu
239Pu
234,
Maximum
Observed Concentration
pCi/kg of Wet Tissue
33
12
13
Dose Factor
mrem:pCi/day
0.27
0.31
0.036 .
50-Year Dose
mrem
4.5
1.9
0.2
                                                TOTAL  7

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                                 DISTRIBUTION
 1 - 40  Environmental Monitoring and Support Laboratory -Las Vegas
     41  Mahlon E. Gates, Manager, ERDA/NV, Las Vegas, NV
     42  Troy E. Wade, ERDA/NV, Las Vegas, NV
     43  Bennie G. DiBona, ERDA/NV, Las Vegas, NV
     44  David G. Jackson, ERDA/NV, Las Vegas, NV
     45  Arthur J. Whitman, ERDA/NV, Las Vegas, NV
     46  Elwood M. Douthett, ERDA/NV, Las Vegas, NV
47 - 48  Ernest M. Campbell, ERDA/NV, Las Vegas, NV
49 - 50  Paul B. Dunaway, ERDA/NV, Las Vegas, NV
51 - 52  Mary G. White, ERDA/NV, Las Vegas, NV
     53  Roger Ray, ERDA/NV, Las Vegas, NV
     54  Robert W. Taft, ERDA/NV, Las Vegas,  NV
     55  Leon Silverstrom, ERDA/NV, Las Vegas, NV
     56  John 0. Cummings, ERDA/NV, Las Vegas, NV
     57  Bruce W. Church, ERDA/NV, Las Vegas, NV
58 - 59  Technical Library, ERDA/NV, Las Vegas, NV
     60  Chief, NOB/DMA, ERDA/NV, Las Vegas,  NV
     61  Martin B. Biles, DOS, ERDA/HQ, Washington, DC
     62  Tommy F. McCraw, DOS, ERDA/HQ, Washington, DC
     63  Major General Joseph K. Bratton, Asst. Gen. Mgr.,
         DMA, ERDA/HQ, Washington, DC
     64  Gordon F. Facer, DMA, ERDA/HQ, Washington, DC
     65  James L. Liverman, Director, DBER, ERDA/HQ, Washington, DC
     66  Robert L. Watters, DBER, ERDA/HQ, Washington, DC
     67  John S. Kirby-Smith, DBER, ERDA/HQ,  Washington, DC
     68  L. Joe Deal, DOS, ERDA/HQ, Washington, DC
     69  Charles L. Osterberg, DBER, ERDA/HQ, Washington, DC
     70  Robert W. Wood, DBER, ERDA/HQ, Washington, DC
     71  Harold F. Mueller, ARL, NOAA, Las Vegas, NV
     72  Gilbert J. Ferber, ARL, NOAA, Silver Spring, MD

-------
 75  Wiliam A.  Mills,  Dir.,  Div.  of Criteria and Standards,
     ORP, EPA,  Washington, DC
 76  Floyd L.  Galpin,  Dir.,  Field Operations Div., ORP, EPA,
     Washington,  DC
 77  E. David  Harward, Dir., Technology Assessment Div.,
     ORP, EPA,  Washington, DC
 78  Albert C.  Printz, Jr.,  Dir., Office of Technical  Analysis,
     Washington,  DC
 79  Library,  EPA, Washington, DC
 80  Richard L. Blanchard, Director, Radiochemistry and Nuclear
     Engineering Branch, EPA, Cincinnati, OH
 81  Peter Halpin, Chief, APTIC,  EPA, Research Triangle Park, NC
 82  Paul DeFalco, Jr., Regional  Admin., Region IX, EPA,
     San Francisco, CA
 83  James K.  Channel 1, Regional  Radiation Representative,
     Region IX, EPA, San Francisco, CA
 84  Charles R. Porter, Dir., Eastern Environmental Radiation
     Facility, EPA, Montgomery, AL
 85  K. M. Oswald, Mgr., Health and Safety, LLL, Mercury, NV
 86  Bernard W. Shore, LLL,  Livermore, CA
 87  James E.  Carothers, LLL, Livermore, CA
 88  Howard W. Tewes,  LLL, Livermore, CA
 89  Lawrence S. Germain, LLL, Livermore, CA
 90  Paul L. Phelps, LLL, Livermore, CA
 91  Mortimer L. Mendelsohn, LLL, Livermore, CA
 92  J. C. Hopkins, LASL, Los Alamos, NM
 93  George E. Tucker, Sandia Laboratories, Albuquerque, NM
 94  Harry S.  Jordan,  LASL,  Los Alamos, NM
 95  Arden E.  Bicker,  REECo, Mercury, NV
 96  Savino W. Cavender, REECo, Mercury, NV
 97  Carter D. Broyles, Sandia Laboratories, Albuquerque, NM
 98  Melvin L.  Merritt, Sandia Laboratories, Albuquerque, NM
 99  Richard S. Davidson, Battelle Memorial Institute, Columbus, OH
100  Steven V.  Kaye, Oak Ridge National Lab., Oak Ridge, TN
101  Leo K. Bustad, College  of Veterinary Medicine, Washington
     State University, Pullman, WA
102  Leonard A. Sagan, Palo  Alto  Medical Clinic, Palo Alto, CA

-------
      101   Leo K.  Bustad, College of Veterinary Medicine,  Washington
           State University, Pullman, WA
      102   Leonard A.  Sagan, Palo Alto Medical  Clinic,  Palo  Alto,  CA
      103   Vincent Schultz, Washington State University,  Pullman,  WA
      104   Arthur Wallace, University of California,  Los  Angeles,  CA
      105   Wesley E.  Niles, University of Nevada,  Las Vegas, NV
      106   Robert C.  Pendleton, University of Utah,  Salt  Lake, UT
      107   William S.  Twenhofel, U.S. Geological  Survey,  Denver, CO
      108   Lloyd P. Smith, President, Desert Research Institute,
           University  of Nevada, Reno, NV
      109   Paul  R. Fenske, Desert Research Institute, University of
           Nevada, Reno, NV
      110   Verle R. Bohman, University of Nevada,  Reno, NV
      111   Manager, Desert National  Wildlife Range,  U.S.  Fish and
           Wildlife Service, Las Vegas, NV
      112   Supervisor, Region III, Nevada Fish and Game Department
           Las Vegas,  NV
      113   Paul  Lyons, Nevada Wildlife Research,  Division of Archives,
           Capitol Building Annex, Carson City, NV
      114   Deward W.  Efurd, McClellan Central Laboratory,
           McClellan Air Force Base, CA
      115  L. L. Skolil, San Diego State University,  San  Diego,  CA
116 - 142   Technical  Information Center, ERDA, Oak Ridge, TN
           (for public availability)

-------