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horn concentration areas.

METHODS AND PROCEDURE

A dye spraying device for marking bighorn, developed by Hansen
(1964) and improved upon b.v Simmons and Phillips (1966), was in-
stalled at the upper spring in Carrizo Canyon above Palm Desert. The
sprayer was installed by the first of May to allow the bighorn time
to become accustomed to it. American Cyanamid Company's Calcocid
Blue AX Double Dye was used. This nontoxic dye was mixed in a
50% solution of isopropyl alcohol. The lower spring and a water trovigh
in Carrizo Canyon were covered with brush from June 22 to July 13
to force the bighorn to come to the upper spring to be marked. Big-
horn Avere mark(Hl from June 29 to July 10. After marking was com-
pleted, the brush was removed.

1 Accepted for publication February 1968.



(289)



290 CATJFOKXTA FTSTT AXD r,A:\rE

An effort was inado to loarn liow often the sheep came to drink
durin<j: tliree 5-da,y periods between June 28 and Jnly 24. A search was
m;\(\o to h)cate marked bip'horn at least 2 days of every week in July
and tlie last 3 weeks in August. Several days in September were spent
locating bighorn in the study area.

Tlie Department's annual bighorn waterhole count, held July 7
to 10, jirovided a cheek on the movement of these marked sheep. The
count covered 10 waterholes. Particijiants in the count were members
of the U.S. Forest Service, California Department of Parks and Eec-
reation, U. S. Bureau of Land Management. U. S. Bureau of Sport
Fisheries and Wildlife, University of California, and the T^niversity of
Eedlands.

"Weather records were obtained from llie University of California
Desert Laboratory, at the mouth of Deep Canyon (Table 1). We re-
corded air temperatures at the upper spring in Carrizo Canyon. On-
site temperatures were approximately 2 F cooler than the maximums
recorded at the Desert Laboratory.

RESULTS OF THE MARKING OPERATION

We intended to mark all of the bighorn that came to Carrizo Spring.
However, at least nine bighorn came to the spring and drank without
being marked. This was partly due to operating difficulties with the
spray gun on July 7.

The marking device worked Avell. Excessive mechanical noise was
eliminated by assembling the marking device so that the solenoid
plunger did not hit the head of the chamber.

Twenty bighorn were marked; seven were sprayed twice with dye.
One ewe w^as not marked because a conspicuous hole in the horn was
sufficient for identification. The first two bighorn marked appeared
less reluctant to kneel under the marking gun than those that fol-
lowed. Later they knelt to drink uneasily, especially if there was wet
dye on the ground.

The dye faded considerably on the hair witliin 10 to IG days, but
remained clearly visible on the horns. Most of the bighorn were shed-
ding when they were marked. It rained on July 17 and 18, washing
some of the dye off the bighorn. By this time it was obvious that the dye
was retained best on the liorns.

By August 18 there had been 2 days of fairly heavy rain and 6
days of light showers in the area. Bain faded the water-soluble dye
rapidly. Forty-five days after marking, the dye was difficult to see on
th(> horns with a 20-i)()wer spotting scope, and was not visible on the
hair. By the end of August, the dye was gone.

Summer Population Density

With the aid of the 20 marked sheep and observations on sex, horns,
and other physical characteristics, we were able to get a count of 33
individual bighorn in Cari-izo Canyon dui-ing flic marking period. Sex
and age ratios of the 33 bighorn classified by the first week of July
were 100 ewes: 84 rams: 40 lambs: 23 yearlings.

Within the concentration area of 4^ square miles in tlu^ Carrizo
drainage and adjacent ram area (Figure 1), there were at least seven
bighorn per square mile in July and August.



SUMMER WATER REQUIREMENTS DESERT BIGHORN



291



TABLE 1

Weather Records Obtained From the University of California Desert
Laboratory, Located at the Mouth orf Deep Canyon







Daily Temperature (F)






June


July


August


September




Max.


Min.


Max.


Min.


Max.


Min.


Max.


Min.


1 . ..


72
78
84
88
92
92
79
76
88
91
98
94
91
84
75
74
80
85
88
91
92
91
89
89
81
80
92
95
96
97


58
54
58
60
64
65
66
68
55
64
68
71
67
63
63
61
56
62
01
67
67
65
64
64
63
56
63
73
73
76


100

105

100

108

103

106

105

99

95

97

96

97

95

90

96

98

94

94

98

99

98

94

97

97

96

98

101

102

92

94

103


72
76
86
84
83
80
81
75
74
75
71
70
71
79
82
80
80
74
79
72
72
71
76
77
71
72
70
84
76
74
78


103

102

104

101

102

102

97

94

105

96

91

95

100

92

94

95

90

95

92

90

94

92

94

97

98

100

97

102

103

97

96


80
79
78
75
80
80
81
78
81
83
79
78
85
78
76
80
78
74
73
78
78
08
68
70
76
78
78
81
87
74
73


94
93

94
90
84
81
82
88
92
94
92
93
96
101
103
80
76
72
70
83
80
92
96
94
91
91
85
77
79
84


70


2


71


3 ._ ...


78


4 - -


74


5


68


6 . .


70


7 . . - - -


63


8


60


9 ... -


73


10


74


11 . .


69


12 ... . -


68


13 .. ...


73


14 - . . -.


76


15


77


16


73


17 ...


62


18


63


19 _ . ...


58


20 . . . .


57


21 -.


68


22 ......


65


23


78


24 . .. .-


78




69


26 -.


68


27

28


63
63




61


30 . . ...


67


31 -









Precipitation (inches)



June


July


August


September


October


Total 0.00


17 0.32

18 0.27

29 0.05

Total 0.64


7 0.52

11 T

16 0.32

Total 0.84


6 0.05

Total 0.05


Total 0.00



It rained hard in Carrizo Canyon on August 10. Showers which fell over Carrizo Canyon on August
14, 15, and 17 were not recorded at the mouth of Deep Canyon.



Frequency of Trips to Water

After June 27, the weather turned hot (Table 1). On June 29, the
bighorn started coming regularly to the upper spring in Carrizo Can-
yon. Some of these bigliorn came to the spring nearly every day dur-
ing the 12-day marking period, but they did not drink on each trip to
the spring. Possibly some of the ewes and young sheep did not drink



292



CALIFORNIA I-MSII AXD GAME



116 25







/Roncho
/ Mirage



Palm Desert



33 40



Ram Area



r "" *" ■*. Concentration Area



A Marking Site
Q,Spring
CI7 Water Trough



2 Miles



Scole



FIGURE 1— Map of the study area in the Santa Rosa Mountains, Riverside County, showing
the location of the summer concentration area in 1965.



SUMMER WATER REQUIREMENTS DESERT BIGHORN 293

on one or two of the trips to water because of disturbance caused by
the marking.

Following 5 hot days (July 2-6), wdth the temperature reaching 102
to 104 F in the shade, there were 21 bighorn at the spring for 2 days
in succession. Most of these drank at least once during the 2 days. For-
tunately, by this time we had marked most of these sheep, so that they
could be identified. On July 9, the weather turned slightly cooler,
with maximums in the 90 's. Only three ewes and one mature ram came
to the spring on July 10.

Between July 20 and 23, we were able to locate most of the marked
bighorn. During this period they followed about the same pattern of
travel and drinking as they did between June 29 and July 9.

Some of the ewes and lambs took a drink 5 or 6 days of the 12 days
that they came to the spring. Twice ewes came to water without their
lambs. One- and 2-year-old rams usually accompanied the ewes and
lambs to the spring and drank about as frequently as the lambs. Prime
and older rams did not water in July as often as the ewes with lambs.
Water was available in potholes during much of August because of
frequent showers. After these rains had produced new growth on the
vegetation, the bighorn made fewer trips to the waterholes.

Welles and Welles (1961) reported that bighorn in Death Valley
drank every day if near water, but 1 to 3 full days without watering
were common. Our brief survey indicated yearlings and ewes with lambs
visited a waterhole daily or every other day in hot, dry weather.

Area Used by Bighorn During the Summer

It is 6 miles from Carrizo Canyon to Magnesia Spring, the nearest
waterhole to the north in bighorn habitat. It would take a strong man
1 day to make this hike over the same route that a bighorn would travel.
The nearest springs from Carrizo Canyon to the south are in Deep
Canyon, 1^ miles southeast of Carrizo Spring.

We did not find any sign that the bighorn of Carrizo Canyon traveled
to Deep Canyon in July and August 1965. However, we have seen big-
horn travel this route in other summers.

During the July and August observation periods the ewes, lambs,
and young rams were observed to stay w^ithin three-quarters of a mile
of the w\aterholes in Carrizo Canyon. Most of the time the bighorn
stayed wdtliin a half-mile cruising radius of a spring during the hot
summer period. The longest distance ewes and young bighorn traveled
in 1 day was 1| miles. Most of the time they covered less ground. Rams
traveled as far as 3 miles from w^ater during July and the first 2 weeks
in August. After the middle of August, the beginning of the rutting
season, the rams stayed nearer the waterholes.

We have observed a similar pattern of bighorn distribution between
Cat Canyon and Highway 74 (Figure 1) in other summers. Jones et al.
(1957) found the same bighorn distribution during the summer of 1953
in Carrizo Canyon as we did in 1965.



294 CALIFORNIA FISH AND GAME

DISCUSSION

Water Distribution

Cnn-izo Canyon ewes and lambs ranged up to Ihrcc-ijuai-lcrs dl' ;i mile
from Avater during tlie summer of lf)65. Kanis range over a much larger
area and make fewer trips to water. Adequate water distribution in
suitable habitat is at intervals of 1\ to 2 miles in the Santa Kosa Moun-
tains. Where springs are loeated 2 miles or less apart in these moun-
tains, we liave observed bands of bighorn 1i-a\('ling from one si)riiig Id
another in the summer.

Water Development

Most of the springs in the bighorn habitat of these mountains have
been developed. There are five waterless areas on the desert slopes of
these mountains that are used by a few rams during tlie summer. To
])rovide water for ewes and young bighorn in these areas would require
installation of rain catchment devices. Helicopters could be used to
move equipment into the development area.

Human inroads upon the bighorn habitat in Magnesia Canyon in
1064 and 1905 provided an important sidelight on future water develop-
ment and bighorn management. In March 1954 a tank was blasted out
of a rock face below^ the Magnesia Spring seep by the Department of
Fish and Game (Weaver, Vernoy, and Craig, 1959).

In years when there was water in this tank, bighorn used it heavily
during the summer. This waterhole is now about 1 mile from a resi-
dential area. Vandalism of the tank and year-round picnicking at this
location in 1964 and 1965 discouraged bighorn from using this water-
hole. No bighorn tracks were found at this waterhole in July or August
of 1965. Bighorn that formerly drank at Magnesia Spring went to a
water trough recently constructed in Bi-adley Canyon, where they were
not disturbed. This trough, built by local residents, is located 1 'j miles
north of Magnesia Spring.

This incideiit shows that bighorn avoid water where there is r(>pea1ed
human disturbance, and demonstrates that the animals readily adapt
to a new water source.

Evaluation of the Waterhole Counts

The Department has conducted bighorn waterhole counts in the Santa
Rosa Mountains since 1958. Avith the exception of 1960 (Blong. 1965).
These counts have been held for 3 to 4 days at eight waterholes when
the Aveather first turns hot in th(> summer. The principal objectives
Avere to record ])opulati(m trend, sex ratios, and age composition. A
better evaluation of previous counts is made possible by experience
gained from the marking study.

Waterhole counts must be held at the same time each year, in the
same areas, and for the same ncM-iod of time to obtain accurate informa-
tion. The Avaterholes should be rei^rescntative of the entire mountain
range. Bighorn behavior should be taken into account. A more complete
count is obtained if it is held during extremelv hot Aveather. We knoAV
that some bio-horn Avater on bright moonlight nights and rams often
drink at daAvn.



SUMMER WATER REQUIREMENTS DESERT BIGHORN 295

In measuring population trend, the waterhole count has two factors
for error that oppose each otlier. One is duplication, which applies
mostl}' to ewes and young bighorn. This error becomes greater each day
of the count. The other factor is that some of the bighorn may not visit
the waterholes from 4 to 8 days. The longer the waterholes are watched,
the greater the opportunity to observe most of the local population as
well as bighorn from nearby waterholes. In these mountains, 3 days of
counting appear to be adequate for lamb survival information as well
as to detect major fluctuations in the population. This length of time
also minimizes duplication. Some of the bighorn using the waterholes
may escape observation but when counts are made for a number of
years they provide an index to the relative abundance of bighorn in
the mountain range.

Very likely more than 33 bighorn lived in Carrizo Canyon and the
adjacent ram area in the summer of 1965. A few rams that were not
seen during the counting period were in the area later in the summer.
Rams characteristically travel from one waterhole to another during
the summer (Welles and Welles, 1961; Simmons, 1964). It appears that
33 is close to the maximum number of bighorn that water in Carrizo
Canyon. The largest number of bighorn counted during a previous
waterhole count in Carrizo Canyon was 27. Jones et al. (1957) recorded
26 bighorn for the Carrizo drainage in 1953.

SUMMARY

A survey was made in 1965 to obtain a better understanding of
desert bighorn dependence upon water in the Santa Rosa Mountains
during the summer. Twenty bighorn were marked in a 12-day period
at one spring by using Hansen's dye spraying device. This made it
possible to identify 33 bighorn in the summer concentration area. The
nontoxic dye could be seen on the horns of the sheep for li months.
Many of the ewes, lambs, and young bighorn came nearly every day
to the waterholes before the summer showers occurred. During July
and August the ewes, lambs, and young bighorn stayed witliin three-
quarters of a mile of the waterholes. Rams in their prime or older
traveled as far as 3 miles from water and made fewer trips to water
during July and the first half of August.

Adequate water distribution for bighorn in the Santa Rosa Moun-
tains is at intervals of 2 miles.

A clearer insight was obtained into such problems as duplication and
frequency of trips to water that complicate the evaluation of bighorn
waterhole count data.

ACKNOWLEDGMENTS

It would have been impossible to properly watch the waterholes and
search the area for bighorn without the assistance of William Asserson,
Edmund Green, William Sproul, and Robert Vernoy of the Department
of Fish and Game and John Lively of the U. S. Forest Service.



296 CALIFORNIA FISH AND (iAMt:

REFERENCES

Blong, Bonnnr. lOG."). Status of hiuliorn in the Santa Knsa Mminlaiiis. Trans.
Desert Bighorn Council, !> : 1-5.

Hanson, Charles G. 19G4. A dye spra.ving device for marking desert iiigliorn shooii.
.lour. Wildl. Mangt., 28 (3) : 584-587.

Jones, Fred L., (Jlonn Flittner, and Bic-hard Gard. 1957. Beport on a survey of
bighorn sheep in the Santa llosa Mountains, Bivorside Count.\'. Calif. Fish and
Game, 43 (3) : 179-191.

Simmons, Norman M. 19(»4. A desert l)igh(un study; part two. Trans. Desert Big-
horn Council, 8 : 103-111.

Simmons, Norman M., and J. L. Phillips. 19(50. ]\Ioditifations of a dye-spraying
device for marking desert bighorn sheep. Jour. Wildl. Mangt., 30 (1) : 208-209.

Weaver, Bichard A., Floyd Vernoy, and Bert Craig. 1959. Game water development

on the desert. Calif. Fish and Game, 45 (4) : 333-342.
Welles, Balph E.. and Florence B. Welles. 1901. The bi-horn of Deatli N'alley.

U. S. Nat. Park Serv., Fauna Ser. : G : 242 p.



Calif. Fish and iUune, 54(4; : 1207-303. 1908.



THIRD COOPERATIVE SURVEY OF THE
CALIFORNIA CONDOR^

FRED C. SIBLEY 2
U.S. Fish and Wildlife Service

ROBERT D. MALLETTE
California Department of Fish and Game

JOHN C. BORNEMAN
National Audubon Society

RAYMOND S. DALEN
U.S. Forest Service

The third annual C«!ifornia condor (Gymnogyps csilifornianus) survey
was conducted October 17 and 18, 1967. One hundred fifty sightings
were reported from 19 of 67 stations manned on October 17, 1967.
Seventy-five sightings were reported from 21 of 68 stations manned on
October 18, 1967. These sightings, by an evaluation of field reports,
were reduced to a minimum count of 46 and 33 individual birds, re-
spectively, for the 2-day survey. A decrease of 5 birds on the first day
of the 1967 survey from the count of 51 birds during the 1966 survey
does not necessarily indicate a decrease in the condor population. The
evaluation procedures have been the same through all three annual
surveys, and results are conservative minimum population counts. The
actual condor population is in all probability greater than the minimum
population figure arrived at in the survey.

INTRODUCTION

The first cooperative survey of the California condor was conducted
in October 1965 (Mallette and Borneman, 1966) and the second in
October 1966 (Mallette et al., 1967). The survey procedures are co-
ordinated by a Condor Survey Committee representing the California
Department of Fish and Game, U. S. Fish and Wildlife Service, U. S.
Forest Service, National Audubon Society, University of California,
and other conservation interests.

Objectives of the survey are to: (i) establish periodic condor popu-
lation counts which will provide an index to the population; (ii) gain
an indication of nesting success based on the age classification of birds
observed; (iii) obtain more information on the distribution of condors;
(iv) foster public awareness of the precarious status and problems
related to the protection of the species; and (v) gain other knowledge
of condors and raptors as incidentally provided by such survey.



1 Accepted for publication April 1968. A contribution from Federal Aid In Wildlife

Restoration Project W-47-R, "Upland Game Investigations".

2 Prepared for and with approval of the Condor Survey Committee : Chairman Ben

Gladlng, Chief of Wildlife Management Branch, California Department of Fish
and Game ; A. Starker Leopold, Professor of Zoology, University of California :
William P. Dasmann, U. S. Forest Service ; Clinton H. Lostetter, U. S. Fish and
Wildlife Service ; .John C. Borneman, National Audubon Society ; Fred C. Sibley,
U. S. Fish and Wildlife Service ; and Robert D. Mallette, California Department
of Fish and Game.



( 297 )



298



CALIFORNIA FISH AND GAME



METHODS

The methods and evaluation jji-dccdures were essentially as reported
for tlie 1965 and 19G6 surveys (Mallette and Borneman, 19(){]; IMallette
et al.. 1907). Clianges in tlie 1967 survey involved minor sliifts in
station locations and the establishment of survey headquarters in
Bakersfield. The evaluation procedures and jjliilosopliy are described
in more detail in Ihc discussion section.

WEATHER

The weather on both days was fair and warm, with mainly easterly
winds of 10 to 15 miles per hour. Except for increased haze causing
reduced visibility the afternoon of October 18, observers reported little
difference in conditions between the two days. The Timber Canyon
fire, located in Ventura County at the lower od^e, of the condor rantxe,
caused abandonment of several stations, and tlie smoke restricted visi-
bility at a few other stations. Table 1 presents weather conditions at
five stations, for comparison Avith conditions in other j^ears.

TABLE 1

U.S. Forest Service Lookout Stations Reporting Weather Information
Which Were Also Condor Survey Stations

Readings Were Taken 2 p.m. October 17 and 18, 1967

October 17



Lookout station


County


Average
wind

velocity

(miles

per hour)


Direction

of

wind

(from)


Temperature
(F)


Relative
humidity


Thorn Point


Ventura


6
6
8
6
10


S

SE

SW

W

NW


72
81
74
81
80


4


Nordhoff . .


Ventura





M cPherson


Santa Barbara

Santa Barbara.

San Luis Obispo


9


Figueroa


G


Hi Mountain


11







October 18



Thorn Point


Ventura


9
8
2
fi
8


SE

SE

NE

S

K\V


09
78
69
87
80


11


Nordhoff


A'cntura


13


McPherson . .


Santa Barbara

Santa Barbara

San Luis Obispo


20


Figueroa


9


Hi Mountain


13







RESULTS

Duriu": the survey 69 stations were manned by L3n observers. On
October 17, 150 condor sightings were reported from 19 stations. These
sightings, by an evaluation of the reports, were reduced to 46 indi-
vidual condors. The age classification breakdown was 3 juveniles, 1
immature, 4 subadults, 30 adults, and 8 unknown. An estimated 1,287
raptors of 11 species were also reported on the first day of the survey
(Table 2).



THIRD CALIFORNIA CONDOR SURVEY



299



TABLE 2
Raptors Reported During Condor Survey October 17—18, 1967



Species



Date reported



Oct. 17


Oct. 18


906


1,206


77


67


1





25


20


29


38


122


225


11


71


3


2


1


3


67


57





1


2


8


43


51



Turkey vulture, Catharles aura

Golden eagle, Aquila chrysaetos

Bald eagle, Haliaeeius leucocephalus

Sharp-shinned hawk, Accipiter striatus

Cooper's hawk, Accipiter cooperii

Red-tailed hawk, Buteo jamaicensis

Swainson's hawk, Buteo swaitisoni

Rough-legged hawk, Buteo lagopus

Pigeon hawk, Falco columharius

Sparrow hawk, Falco sparverius

Prairie falcon, Falco ynexicanus

Marsh hawk. Circus cyaneus

Miscellaneous raptors

Totals-



1,287



1,749



On October 18, 75 condor sightings were reported from 21 stations.
By an evaluation of the reported sightings, 33 individual condors were
seen. The age classification breakdown was 2 juveniles, 4 inimatures,
1 subadult, 23 adults, and 3 unknown. The observers also reported an
estimated 1,749 raptors of 11 species (Table 2).

The details of individual sightings have not been included in an
appendix, as was done for the 1965 and 1966 surveys. Copies of the
supporting data are available for review at the office of the California
Department of Fish and Game, 1416 Ninth Street, Sacramento, Cali-
fornia. Observation station locations and sighting success are plotted



in Figure 1.



DISCUSSION



During the past year many questions have been asked concerning
interpretation of the survey results. Some of these reflect a considerable
misunderstanding of the purpose of the survey and its evaluation and
results. A discussion of these aspects has therefore been included in
this paper.

The condor survey was initiated to develop methods of quickly de-
tecting significant changes in the condor population. The methods used
by Koford (1953) and Miller, McMillan, and McMillan (1965) give
population trends over a long period and are not applicable to an
annual population survey. The cooperative condor survey is still in an
experimental stage, and results are not yet comparable. Although not
yet indicating changes in population, the results have confirmed a
minimum population figure higher than previous estimates. The survey
is essentially a simultaneous count of condors, and the resultant figure
may be considered the minimum number of condors still in existence.
The 1967 count may be correctly quoted only as 46 plus, not as 46
plus or minus.

Survey methods have been described by Mallette and Borneman
(1966) and wall only be reviewed here. Rapid reporting of sightings



300



CALIFORNIA FISH AND GAME





CONDOR SURVEY 1967



Q Observation stotions at wtiich one or more
condors were sighted on October 17, 1967

O Observation stations at which one or more
condors were sighted on October 18, 1967

O Observation stations at which one or more
condors were sighted on October 17 and 18, 1967

• Observation stations at which no condors
were sighted

Condor Sanctuaries



T i ll Condor Range



FIGURE 1— Locations of condor survey observation stations and sightings on October 17 and

18, 1967. Drawing by CliRa Corson.


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