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California. Dept. of Fish and Game.

California fish and game (Volume 42, no. 4)

. (page 1 of 11)



CALIFORNIA!

FISH- GAME

"CONSERVATION OF WILDLIFE THROUGH EDUCATION"







California Fish and Game is a journal devoted to the conserva-
tion of wildlife. Its contents may be reproduced elsewhere pro-
vided credit is given the authors and the California Department
of Fish and Game.

The free mailing list is limited by budgetary considerations to
persons who can make professional use of the material and to
libraries, scientific institutions, and conservation agencies. Indi-
viduals must state their affiliation and position when submitting
their applications. Subscriptions must be renewed annually by
returning the postcard enclosed with each October issue. Sub-
scribers are asked to report changes in address without delay.

Please direct correspondence to:

LEO SHAPOVALOV, Editor
Department of Fish and Game
722 Capitol Avenue
Sacramento 14, California

Individuals and organizations who do not qualify for the free
mailing list may subscribe at a rate of $2 per year or obtain indi-
vidual issues for $0.75 per copy by placing their orders with the
Printing Division, Documents Section, Sacramento 14, California.
Money orders or checks should be made out to Printing Division,
Documents Section.



u









1

1



V



VOLUME 42



OCTOBER, 1956



NUMBER 4




Published Quarterly by the

CALIFORNIA DEPARTMENT OF FISH AND GAME

SACRAMENTO



STATE OF CALIFORNIA

DEPARTMENT OF FISH AND GAME



GOODWIN J. KNIGHT
Governor



FISH AND GAME COMMISSION

HARLEY E. KNOX, President
San Diego

WILLIAM J. SILVA, Commissioner WELDON L. OXLEY, Commissioner

Modesto Redding

CARL F. WENTE, Commissioner ANDY KELLY, Commissioner

San Francisco Los Angeles



SETH GORDON
Director of Fish and Game



CALIFORNIA FISH AND GAME
Editorial Staff

LEO SHAPOVALOV, Editor-in-Chief — Sacramento

JOHN E. FITCH, Editor for Marine Fisheries Terminal Island

CAROL M. FERREL, Editor for Game Sacramento

J. B. KIMSEY, Editor for Inland Fisheries Sacramento



TABLE OF CONTENTS

Page

Pood Habits of the Greal Basin Deer
Herds of California _Howard R. Leach 243

Average Lunar .Month Catch of Sardine
Fishermen in Southern California,
1932-33 Through 1954-55 .Frances N. Clabk 309

A Tagging Experiment With Channel
Catfish (Ictalurus punctatus) in the
Lower Colorado River George W. McCammon 323

Largemouth Bass Tagging _ -T. l'>. Ki.mskv 337

A Simple Optic Bench for Scale Photomi-
crography- Harry M. Mekjiax and Jack \Y. Scitott 347

Note

Conditioned Space Response in an
Aquarium Tank by the California
Yellowtail, Seriola dorsalis Earl S. Herald 351

Reviews — 353

Index to Volume 42 359



(l>ii .



FOOD HABITS OF THE GREAT BASIN DEER
HERDS OF CALIFORNIA'

HOWARD R. LEACH

Game Management Branch

California Department of Fish and Game

TABLE OF CONTENTS

Page

[INTRODUCTION -••

ACKNOWLEDGMENTS 245

HIS ruin' OF DEER COLLECTIONS- 245

METHOD OF STIHV 245

PRESENTATION OF DATA 247

CLIMATE ___ 247

DEVILS GARDEN DEER HERD 247

Description of Area 247

Vegetative Composition of the Range 247

Migration 250

Food Habits 250

Climatic Conditions as They Affect Food Habits 255

Summer Food Habits 260

LASSEN-WASHOE DEER HERD (DOYLE SUBUNIT)^ 260

I rescription of Area 260

Vegetative Composition of the Range 260

Migration 262

Food Habits _ 262

Climatic Conditions as They Affect Food Habits 267

Summer Food Habits 273

SIERRA VALLEY DEER HERD (VERDI SECTION) 274

Description of Area -71

Food Habits - 2711

INYO DEER HERD.. — 279

Description of Area _- __ 279

Vegetative Composition of the Range 281

Migration __. 282

Food Habits _ — 2S6
FSF OF WINTER DIE-OFF DEER FOR FOOD HABITS

DETERMINATION — 291

SUMMARY 292

REFERENCES — 293

APPENDIX-CLIMATOLOGICAL DATA 295

1 Submitted for publication June, 1956. Tbis study was carried out with funds pro-
vided by Federal Aid in Wildlife Restoration Project California W-25-R, "Food

Habits Investigations", with Project W-35-R, "Wildlife Disease Studies" and
W-41-R, "Big Game Studies", cooperating.

( 1-43 )



244



' AI.IFDKXIA FISH AND GAME



INTRODUCTION

East of the Sierra Nevada and the Cascade Kange lies a section of
California considered geographically t<> be an extension of the Greal
Basin of tin- western United suites. It is characterized by a sagebrush
climax. Inhabiting this area in California are the Rocky Mountain nude
deer, Odocoileus hemionus hemionus (Rafinesque), and the [nyo mule
deer, Odocoileus hemionus inyoensis (Cowan) (Figure 1). These decl-
are largely migratory, summering high in the Sierra Nevada and the
Cascade Range and wintering in the foothills and adjacenl lower eleva-
tions in the < rreal Basin.

The purpose of this study was to determine the food habits of
Rocky Mountain and Inyo mule deer on the Great Basin winter
ranges in < 'alifornia, in an effort to contribute to a better understanding



z Odocoileus h. hemionus
Odocoileus h. inyoensis

Devi Is Garden Range

2. Lassen Washoe Range

3. Verdi Range

4. North Inyo Range

5. South Inyo Range




FIGURE 1. Map of the distribution of Rocky Mountain and Inyo mule deer in California,
showing the location of the winter ranges of deer herd management units and subunits.



DEER FOOD EABITS -4~)

of the ecology of deer with respecl to food conditions and climatic
phenomena.

ACKNOWLEDGMENTS

The food habits study presented in this paper is hut a pari of the
laboratory and field research conducted by the California Department
of Pisli and Game in cooperation with the I'. S. Foresl Service, I'. S.
Bureau of Land Management, Oregon State Game Commission, and
Nevada Pish and Game Commission.

Special acknowledgment is given to Trevenen Wright, James Blais-
dell, Robert Lassen, and Fred Jones of the Department of Fish and
Game. They cooperated noi only in the collection of deer stomach
samples, hut also were responsible for many of the field data incorpo-
rated into the study. The material from the authorized special deer
collections was obtained through the line cooperation of the staff of
Department's wildlife disease laboratory, which was given the responsi-
bility of collecting the animals. The author wishes to thank the staff
of the Herbarium of the University of California for use of specimens
and for assistance in the identification of plant materials. To Cliffa
M. Corson is given grateful acknowledgment of the excellent drafting
work on the many charts, graphs, and figures used in the report. Carol
M. Fcrrel contributed substantially to the analyses and assisted in
editing the paper.

Free use was made of published and unpublished reports of the
Devils Garden Interstate Deer Herd Committee, Lassen-Washoe Inter-
state Deer Herd Committee, and California Pittman-Robertson Project
W-41-D. "Big Came Studies".

HISTORY OF DEER COLLECTIONS

The study of the food habits of California's deer herds by the stomach
analysis technique began in 1046. when permission was granted to the
disease staff of the California Department (then Division) of Fish
and Game to collect 60 female deer from the Interstate Deer \h'Vi\
in Modoc County. Subsequently, eolleetions of female deer from other
herds were authorized by the Fish and Game Commissions of Oregon,
Nevada, and California.

The special authorized collections were supplemented by extensive
collections of stomach samples and data from deer made available from
hunter kills, highway mortality, and winter die-offs.

Table 1 is a history of the sources of the 978 stomach samples
reported on in t his paper.

METHOD OF STUDY

stomach samples were obtained in the field by removing a pint or
more of material from the rumen. After appropriate labeling they
were preserved in formalin.

The samples were examined with ;i binocular microsco] quipped

with a T\ ocular and a o.Tx objective. The material was thoroughly
washed through a fine-mesh screen preparatory to examination. After



246



( ILIFORNIA PISH AND CAME



TABLE I
Summation of the Field Collection of 978 Deer Stomach Samples



Deer herd


C6 '>f material




Number


leu


( Commission-authorized ci >1-
lection

\ hi Inn ized colled i In

gon li-h unci ( lame ' 'inn
mission 1

Highwaj mortality
Hunter-killed deer.
Winter die-off


Monthly collection from November,
1946, to April, L947


60




Monthly collection in Oregon from
May to October, 1947


:st




Winters of 1940-47, 1950-51, and
1951-52.


94




Special antlerless hunt, November,
1950


40




February and March, 1952


99




Subtotal .






327








la - , N \\ ashoe. ..


( 'ommission-authorized col-
led ion

Highway mortality.

1 1 uutcr-killcd deer.


Monthly collection in 1951. _.


50




Winters of 1949-50, 1950-51, and
1951-52.


27)




Special antlerless hunt, November,
1951.












Subtotal






343








Verdi—


Commission-authorized col-
lection

] lunter-killed deer


From January to May and from
September to December, 1951- .

September, 1951 —






30
6






Subtotal






30








Inyo.-


< Commission-authorized col-
lection

Winter die-off


From December, 1951, to April, 1952,
and from February to April, 1953_

January to April, 1952






121
151






Subtotal






272




Total .


978









the items in the sample were identified, 2 a visual estimate of the per-
centage of each item was made and recorded. No effort was made to
separate the planl materials or to measure them individually.

In summarizing the data, the aggregate percentage method, as de-
scribed by .Martin, Gensch, and Brown (1949), was used to determine
the volume percentage of food items eaten. The frequency of occur-
rence expressed in percentage was determined by dividing the number
of occurrences of each food item by the total number of samples
mined.



Brov i i have been id.-ntificd :n , ,,, ,im K to McMinn (1939), and forbs and

isses according to Jepson (1923). The scientific names of the plants not found
in the tables have been included in the text.



DEER POOD HABITS 247

PRESENTATION OF DATA

Doer management studies in California have been conducted by re
gions, units, and subunits based on natural deer populations and range
boundaries (Longhursl el al.. 1952). Certain of these units have been
subjected to intensive study. The food habits data represented by the
stomach analyses of 978 Greal Basin Acer have been broken down into
the following four managemenl units and subunits: Devils Garden
deer herd unit, Doyle subunit of the Lassen-Washoe deer herd unit.

Verdi Section of the Loyalton-Truckee subunit of the Sierra Valley

deer herd unit, and Inyo deer herd unit.

To interpret fully the dynamics of the deer herds in relation to
Food habits and range condition it was necessary to present the variable
climatic factors affecting both the deer and the range encountered dur-
ing the course of study. This necessitated the breakdown of the data
into monthly and yearly increments for each deer herd, and the dis-
cussion is arranged accordingly.



"to J



CLIMATE

The climate of the Great Basin is semiarid and characterized by low
ainfall, some subzero temperatures in winter, and warm, dry summers.
'recipitation is generally limited to a period from September through
April. In the northern ranges precipitation normally varies from 8 to
10 indies at the lower elevations to as much as 20 inches in the higher
timbered areas. Semidesert conditions exist in the southern Inyo ranges;
the precipitation may be no more than 5 inches annually. In the
Appendix are included climatological data giving the monthly means
of daily maximum and minimum temperatures, the lowest recorded
monthly temperatures, precipitation, and snowfall representative of
the study areas and of the winter periods concerned.

DEVILS GARDEN DEER HERD
Description of Area

The Devils Garden Interstate deer herd is made up of Rocky Moun-
tain mule deer that summer principally in the Fremont National Forest
in Oregon and winter in the Modoc National Forest in California. The
snnnner range covers approximately 406,000 acres and the winter range
about 375,000 acres. However, the acreage on which the *\ocv spend the
greal part of the winter is much smaller, covering approximately 100,-
000 acres (Interstate \)n'\- Wi^rA Committee, 1!U7).

Geologically, the Devils Garden area is a portion of the Modoc Pla-
teau. It is of volcanic origin, characterized by an undulating plain with
areas of lava overflow and occasional hills rising from .100 to 1,500 feet
above the general plateau level. The elevation in California runs from
4,050 feet at Tulelake to over 5,000 feet at Badger Well and Crowder
Flat.

Vegetative Composition of the Range

The flora of the region is typically Great Basin sagebrush formation
interspersed with other cover type associations i Figures 2, 'â– >. and 4).
The higher portions of the range, notably the Crowder Flat and Badger



248



i ai.ii ORN] \ risii ami i;.\ \n.








FIGURE 2. A general view of the ponderosa pine vegetative type characteristic of much of
the area inhabited by the Devils Garden deer herd during the early portion of the winter.
It is essentially a ponderosa pine-bitterbrush association with open sagebrush flats. Photo-
graph by the author.




FIGURE 3. A transition area predominantly of bitterbrush exists between the ponderosa pine
type and the lower elevations of the winter range, where juniper is dominant. Photograph
by the author.



DEER I'ool) BABITS



249







mam








FIGURE 4.



The Casuse Mountain area, showing the juniper-annual grass type, c
of the lower portions of the winter range. Photograph by the author



haracteristic



Well areas, are characterized by the extension of the ponderosa pine
forest type, which supports an umlerstory dominated by bitterbrush.
Interspersed are open areas of grassland and fiats of sagebrush, :i with
a scattering of Sierra juniper. Associated with the pine forest is the
prostrate-growing squaw carpet, an evergreen shrub, thickly matting
the ground in some areas. Thickets of mature curlleaf mountain ma-
hogany occur principally on the hill slopes and ridges. Extensive brush
fields of greenleaf manzanita and snowbrush fringe the winter range
on the slopes of the higher mountains.

An intermediate area, dominated by bitterbrush. exists between the
pine forest and the lower portions of the winter range. This bitterbrush
association gives way to open flats of sagebrush or grassland inter-
spersed with areas of Sierra juniper. Rubber rabbitbrush and sticky-
flowered rabbitbrush occur as subdominants in this plant association.
Several species of grasses occur throughout the range; certain areas aro
dominated by annual cheat grass. The principal perennial grasses
present are the blue grasses (Poa spp.), squirreltail (Sitanion sp.),
Idaho fescue (Festuca idahoi nsis \ . Junegrass (Koeleria sp.), needle
grasses iSlipa spp.). and rye grasses (Elymus spp.). Forbs for the
most part are frozen out during the first days of frost. Imt available in
the form of dry Leafage are balsam root, mule's ear, and Douglas phlox.
which are widespread over the area. Tumbling mustard is conspicuous
in the disturbed fields in the flats and along the roads.

Table 2 is a summary of the vegetative composition of the Devi's
Garden area based on 204 line-intercepl plots.

8 In this paper "sagebrush" Is considered Artemisia trident at a, although several of

its siiiispri-it-s, as presented by Flail and Clements (!!'-•"• ». may \>v included.



250



CAM! OKNIA FISH AND (IAMK



TABLE 2
Percentage Composition of Vegetation of the Devils Garden Winter Range



Grass

Vnnual grasses —
Perennial grasses.



Total grass.

I orbl

Vniiual forbs

Perennial forbs..



Total forbs.



Browse

Arclostaphi/loa patula Greenleaf manzanita

Artem isin tridentata Sagebrush

Ceanothus prostrutus Squaw carpet

i eanothus velutinus.. Snowbrush

Cei ocarjnu ledifolius Curlleaf mountain mahogany.

Chrysothamntu spp Rabbitbrush

Juniperus occidentalis . . . Sierra juniper

I'inus sp Pine

I'runus emarginata Bitter cherry

Pvrahia tridentata... Bitterbrush

Kibes sp.. Gooseberry

Tetradymia sp Horsebrush

Others



14.2

L'li. I



40.0



10. i

6.9



Total browse

Percentage of ground covered with available forage.



17.3



0.3
21.1

3.8

Trace

0.3

4.4

1.3

0.6

0.3

9.1

Trace

Trace

0.9



42.1
32.0



Migration

The fall migration of deer from Oregon usually occurs in October,
with the mass of deer taking well-defined trails into the northeast por-
tion of the winter range. By late November the deer have moved south-
ward from the Crowder Plat and Blue Mountain areas to the Badger
Well area and tend to concentrate in this general vicinity during De-
cember and January. Movement from this concentration area is deter-
mined by climatic conditions. In an open winter the deer distribute
themselves over a wide area of the winter range, while heavy storms
have a tendency immediately to concentrate the deer in the north-
western portions of the winter range. In very severe winters the deer
remain there until the weather permits a return to more favored areas
to the south and east. By May the deer move northeastward to the
Oregon summer range.

Food Habits

Table 3 is a monthly summary of the food items eaten by 199 Rocky
Mountain mule deer on the Devils Garden winter range, expressed in
volume percentage and frequency of occurrence in percentage. This is
a summary of the food habits of the Interstate deer herd over the three
winters of 1946-47, 1950-51, and 1951-52. The graphical presentation
of this diet is shown in Figure 5. Not included in this summation of
data, but discussed later, are the results of the analyses of the 99 deer
stomachs collected From winter-killed deer in 1!»52.

It is evident from an examination of Table :! and Figure 5 that there
is a definite seasonal trend in deer food habits throughout the winter.



i >i:i:ii !••(>( id ii. M'.ris



251



100



o
ui

<

t-
z

o

or

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M« 0CT -

No.
Specimens 10

FIGURE 5. Graphic representation of the food habits of the Interstate deer herd in the

winters of 1946-47, 1950-51, and 1951-52.

This monthly trend correlates closely with the movement of deer on
the wintering area, which is determined by weather conditions and
food preferences.

Present at the higher elevations of the winter range and accessible to
the tier during the early part of the winter are such browses as cuiv
leaf mountain mahogany, snowbrush, greenleaf manzanita, and squaw
carpet. These plants contribute most heavily to the diet from October
through December, and of these plants, squaw carpet is apparently a
preferred forage. Deer are known to seek- ou1 this plant even when it
is covered by snow.

The consumption of bitterbrush exhibits a definite seasonal utiliza-
tion. As seen in Table 3, bitterbrush made up 59.8 percent by volume
of the October diet and was found in 100 percent of the stomachs, but
by January and .March the consumption of bitterbrush decreased to a
point where it contributed little to the diet.

As bitterbrush use falls off in the late winter months, sagebrush takes
its place as the staple browse in the diet. There was but one occurrence
of sagebrush in the October stomachs and little sagebrush was eaten in
November. Beginning in December, the consumption of sagebrush in-
creased appreciably. It made up 12.2 percent of the December diet and
was found in (i.'!.(i percent of the stomachs; by January and February
it constituted 26.3 and 25.2 percent, respectively, of the diet. This
heavy consumption of sagebrush continued in March, bul decreased
noticeably in April.



252



CALIFORNIA PISH AM> GAME



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Using the text of ebook California fish and game (Volume 42, no. 4) by California. Dept. of Fish and Game active link like:
read the ebook California fish and game (Volume 42, no. 4) is obligatory