Group Title: host-flea relationships in a sylvatic plague endemic region of the southwestern United States, with special studies on some new approaches to plague control /
Title: The Host-flea relationships in a sylvatic plague endemic region of the southwestern United States, with special studies on some new approaches to plague control
CITATION PDF VIEWER THUMBNAILS PAGE IMAGE ZOOMABLE
Full Citation
STANDARD VIEW MARC VIEW
Permanent Link: http://ufdc.ufl.edu/UF00097631/00001
 Material Information
Title: The Host-flea relationships in a sylvatic plague endemic region of the southwestern United States, with special studies on some new approaches to plague control
Physical Description: 89 leaves : ill. ; 28 cm.
Language: English
Creator: Parsons, Ray Edward, 1936-
Publication Date: 1972
Copyright Date: 1972
 Subjects
Subject: Plague   ( lcsh )
Fleas as carriers of disease   ( lcsh )
Dissertations, Academic -- Entomology and Nematology -- UF
Entomology and Nematology thesis Ph. D
Genre: bibliography   ( marcgt )
non-fiction   ( marcgt )
 Notes
Thesis: Thesis (Ph. D.)--University of Florida, 1972.
Bibliography: Includes bibliographical references (leaves 84-89).
Additional Physical Form: Also available on World Wide Web
General Note: Typescript.
General Note: Vita.
Statement of Responsibility: by Ray Edward Parsons.
 Record Information
Bibliographic ID: UF00097631
Volume ID: VID00001
Source Institution: University of Florida
Holding Location: University of Florida
Rights Management: All rights reserved by the source institution and holding location.
Resource Identifier: alephbibnum - 000432014
oclc - 37798766
notis - ACJ1518

Downloads

This item has the following downloads:

PDF ( 4 MBs ) ( PDF )


Full Text









The Host-Flea Relationships in a Sylvatic Plague Endemic
Region of the Southwestern United States, with Special
Studies on some New Approaches to Plague Control











By

RAY EDWARD PARSONS


A DISSERTATION PRESENTED TO THE GRADUATE COUNCIL OF
THE UNIVERSITY OF FLORIDA IN PARTIAL
FULFILLMENT OF THE REQUIREMENTS FOR THE DEGREE OF
DOCTOR OF PHILOSOPHY








UNIVERSITY OF FLORIDA


1972































UNIVERSITY OF FLORIDA
I 1262 08552 4758111111111111 IIII
3 1262 08552 4758





























DEDICATION

To my wife, Anita













ACKNOWLEDGEMENTS


The author wishes to express his gratitude to the Surgeon

General, U.S. Army for making this research possible.

Special thanks go to Colonel D.E. Newson (retired) and

Lt. Colonel W.G. Pearson, entomology consultants, Office

of the Surgeon General.

The author would also like to express his gratitude to

the Chairman of his Supervisory Committee, Dr. F.S. Blanton

for his advise and assistance during the study; to his co-

chairman Dr. D.E. Weidhass, United States Department of

Agriculture, for his advice and guidance, and for the use

of supplies and facilities at the Insects Affecting Man and

Animals Investigations Laboratory; special thanks to Mr. M.M.

Cole of this laboratory for his advice and encouragement

throughout the study; to Dr. W.G. Eden, Dr. J.F. Butler,

Dr. B.J. Smittle, and Dr. D.S. Anthony of his Supervisory

Committee for their interest and advice during his graduate

program. Special appreciation goes to all members of the

staff at the Insects Affecting Man and Animals Investigations

Laboratory.

Sincere gratitude is expressed to Mr. B.E. Miller of the

New MIexico Environment Improvement Agency for making the


iii








field portion of this research possible; to all his staff

members, with special thanks to J.R. Wheeler, and N. Weber,

and former staff members C.D. Rael and D.L. Forcum.

I am also deeply indebted to the Special Forces, U.S. Army.













TABLE OF CONTENTS

Page

ACKNOWLEDGEMENTS. ......... .... ... .......... iii

LIST OF TABLES. .................................. vii

LIST OF FIGURES. .. ................................ ix

ABSTRACT ............................ ....... .. ... xi

INTRODUCTION... .. .......... ....... ..... 1

REVIEW OF THE LITERATURE ........................
Plague-A Brief History........................ 4
Plague-Western United States and Canada....... 5
Plague Epidemiiology.......*................... 6
Host-flea Relationships.. ........ .... ..........
Biology......... .................... ......... 8
Rearin ...................... ........... 9 o
Flca Relationshins ............* ..... ....*. 10
Flea Surveys.................... ............... 10
Animal Relationships............................ 13




Laboratory Studies ........ .. ... . .. . 14

iATERIAL A!ID I!ETHODS .................. ........... 18
Location and Description of the Field Study Area 18
Climate . . . . . .. ................ .. 18
Flora . . . . . . . . ......... ......... 18
Fauna ........... ........................ 19
Selection and Preparation of Study Site....... 20
Preparation and Trapping of Grid.............. 21
Animal Processing..... ........ ...... ...... 23
Laboratory Studies ......... .... ...... ........ 29
!Mlethods and Procedures... .............. ..... 30

RESULTS AM'D DISCUSSION .................... .. ....... 37
Field Studies................................... 37
Discussion of Aspects Relating to the Study
Sit+ .. ..... . . . s o ..** . . . . . . 37
Trapl in-., Results ............................. 38
Population Estimate. ................... .... 4







TABLE OF CONTENTS (Continued)

Page

Trap Preference..........................*.... 41
Animal Species Trapped........................ 45
Host-plague Relationships..................... 47
Animal Temperatures ............... .......... 47
Sex-plague Relationships...................... 48
Host-flea Relationships........*............ 49
Flea Indices...... ..... .. .... .. .. .... . . 52
Laboratory Studies.................. .. .... 66

SU AARY ..................... ... .. .......... 70

APPENDIX I ** ***....................... 71
APPENDIX TI..................................... 74

LITERATURE CITED ................................... 84











LIST OF TABLES


TABLE Page
1. Trapping results, including captures and recaptures
from a 24 x 114 meter study plot on Red Bluff
Ranch, New Mexico, March 13 through July 16
1968. .... ... ... *...................... 39

2. Estimate of the animal population on the 24 x 114
meter study plot on Red Bluff Ranch, New
r Oxico .... .... ... ........................ 42

3. Comparison of trapping success by animal species,
between National (Tomahawk) and Sherman live
traps on Red Bluff Ranch, New .exico....... 44

4. Relative abundance of animals caught during 17
trap nights from March 13 through July 16,
1968 on Red Bluff Ranch, New Mexico........ 46

5. Percent adult males and females of each species
trapped from the 24 x 114 meter study plot
on Red Bluff Ranch, New Mexico............. 50

6. Summary of weekly flea indices for all hosts made
during the study period, IMarch 13, through July
16, 1968 at Red Bluff Ranch, New Mexico.... 53

Appendix I

1. 'l!ean anal temperatures of animals trapped on Red
Bluff Ranch, New Mexico, M.arch 13, through
July 16, 1968 .............. ..... ...... 72

Appendix II

1. monthly indices of flea species on Dinodomvys
re-rirmi, !.arch 13, through July 16, 1968 at
Red. luff Ranch, Now xico................ 75

2. monthly indices of flea species on Dirodoryfv
orJdl, i.arch 13, through July 16, 1968 at
Red Bluff Ranch, New Kexico................ 9

3. >onthly indices of flea species on Dinio]Loia
snectbis1, Ma rch 13, through July .6, 1968
at Red Bluff Ranch, Niew ]exico.......*..... 7







LIST OF TABLES (Continued)

TABLE Pae

4. i.onthly indices of flea species on Orychomys
.eiooaester_, March 13, through July 16, 1968
at Red Bluff Ranch, New :le::ico. .......... 78

5. monthly y indices of flea species on Perogathus
flav-is, iMarch 13, through July 16, 1968 at
Red Bluff Ranch, New oxico. ............ 79

6. monthly indices of flea species on PeroMvscus
!.eucon,-, -:rch 13, through July 16, 1968
at Red Bluff Ranch, New rMexico............. 80

7. Monthly indices of flea species on Neotoma
micropu .:.rch 13, through July 16, 1968
at Red Bluff Ranch, New ].,exico. .......... 81

8. Monthly indices of flea species on SEnrm nhilus
(Citellus) spilosona, :i.rch 13, through
July 16, 1968 at Red Bluff Ranch, New
iexico ........ ....................... 82

9. Monthly indices of flea species on SylVily g
auduhonii, March 13, through July 16, 1968
at Red Bluff Ranch, New !lexico ............ 83


viii












LIST OF FIGURES


FIGURE Page

1. Trans at stake sitc.............. .......... 22

2. Animal field processing laboratory ............. 2L

3. Individual animal data sheet................... 25

4. Telethermometer for taking animal temperatures. 27

5. Weekly summary data sheet...................... 28

6. Rat colony holding cage........................ 31

7. Individual animal holding container............ 34

8. Artificial rat runs ....... ... .... .. .. .... 35

9. Total flea indices for animals collected March
13, through July 16, 1968 at Red Bluff
Ranch, New Mexico ...**...*. .... .***** .. 53

10. Flea index for Dipodomys snectabilis, March 13,
through July 16, 1968, from the study site
on Red Bluff Ranch, New Mexico............. 58

11. Flea index for Dirodomvs snectabilis, December
1969 through December 1970 at Red Bluff
Ranch, New Mexico... .. .. e.*..****.* 59

12. Flea index for NE2 otoa microu2, March 13,
through July 16, 1968, from the study site
on Red Bluff Ranch, New 1Mexico ............. 6

13.. Flea index for Neotorn mieropus., December 1969
through December 1970 at Red Bluff Ranch,
New !"cxico. ........... ............ ...... 61

14. Flea index for Peromvcu( 1 ouconT., llMarch 13,
through July 16, 1968 for the study site
on Red Bluff Ranch, New IMexico ............. 62






LIST OF FIGURES (Continued)


15. Flea i dex for Spemonbilu, (Citelluf) sillosna ',
:Ca.rch 13, through July 16, 1968 from the study
sitc on Red Bluff Ranch, New Zexico........... 63

16. Flea index for Sajl.llgns audubcn ij, "n.rch 13,
th:-'. h July 16, 1968 from the study site on
Red Bluff Ranch, Yew Mexico. ................. 64

17. Flea index for Sv1vila ,s acduboniji, December
1969 through December 1970 at Red Bluff
Ranch, New : exico. . . . .. a . ... 65






Abstract of Dissertation Presented to the Grad lat Cou'nc-l
of the University of Florida in Partial '!lfill-o"nt orf +1.
requirements for the Decree of Doctor of Phiosenhy7

The ost -Flea Relationshins in a Sylvatic Plague Endenic
Roei~on f the Southwestern United States, '!ith Special
S- "''.- on Some New Approaches to Pla~uo Control




RAY :D'.'\A D PARSOC S

June, 1972
Chairman: Dr. F.S. Blanton
Co-chairman: Dr. D.W. Weidhass
MIvajor Department: Entonology and Nematology

Host-flea relationships were studied from March 13,

through July 16, 1968, on a field plot at Red Bluff Ranch,

New I.Coico. Data on host abundance, occurrence of male

versus female animals, and a population estimate were

given, and their relationship to plague discussed. Trap-

ping efficiencies of the two live traps used during, the

study were determined. Total flea indices, and indices

for individual flea species by animal host were given.

A laboratory study was conducted at the U.S. Department

of AT-ricul-ture's Insects Affecting i''an and Animals Lab-

oratory, Gainesville, Florida, 1970-1971. A potential

method for controlling fleas on wild animals was evl.iated,

and other possible solutions to flea control during pla'r.e

enizooticn were discussed.

None animal species, totaling 306 animals and renresent-

ing 903 captures and recapturo:, w.0c-- collected durin- the







studr. fl podonys --r ismJ.. M'e'mrns, was the rrdomia an1i"al

on the study site, it represented 30 percent of the total

nrinals tra=-ned. "'tional (Tomahawki) traps were found more

efficionl- fcr tra.-pping animals on the study site than

Sherman tra Exceptions were the very small animals that

could sli- through the wire sides of the National trap.

F'le indices were determined graphically and in Table

form to show the variation in the two methods. Advantages

and disadvantages of the two methods were discussed.

Flea indices generally declined during the period of study.

A vaseline-fenthion mixture was used in an attempt to

develop a new approach to flea control on wild animals.

The material was placed in artificial rat runs with a bait

in the center of the run. To reach the bait the rat would

have to pass through the sticky mixture. It would then

lick its feet, the material would be taken internally,

act as a systemic insecticide, and kill the fleas placed

on the rats. The method was not considered a practical

flea control measure.


xii












INTRODUCTION

The plague bacillus, Psteirell (Yersinia) nestis

(Lehman and e.eumann), (Herms 1961) has been a scourge to

mankind since time immemorial. We are fortunate today,

with our high standard of living and scientific knowledge

to have this disease for the most part, under control.

Even now, under these conditions, we find the disease get-

ting out of hand, for short periods of time in various parts

of the world. India, over the past 20 years has experi-

enced epidemics of considerable magnitude (Pollitzer 1954).

More recently and extending to the present, we find South

Vietnam an area with a present plague problem of consid-

erable dimension. In 1966, an estimated 5,000 cases occur-

red in the indigenous population, but less than 10 cases

were reported, among United States (U.S.) military person-

nel in the area, although in many cases they were in close

contact with the civilian population. It has been surmised

that the routine immunization given U.S. personnel entering

the area has been effective in preventing plague from this

susceptible population (Cavanaugh 1967).

This disease has never been a major problem in the United

States, although periodic cases have occurred in seaport

cities both on the east and west coasts. These cases were

considered ship-borne plague, i.e., plague brought into the
1







U.S. by infected rats and/or fleas, (Kartman et al. 1967).

This type of plague is non-existent in the U.S. today, but

the potential still exists, especially from the U.S. retro-

grade movement out of South Vietnam.

The primary focus of plague in the U.S. today is in epi-

zootic form. Since McCoy, in 1908. (as cited by Kartman,

1970) discovered plague in the California ground squirrel,

Spermophilus (Citellus) beechevi (Richardson), the disease

has moved eastward as far as the western portions of Texas,

Oklahoma and Kansas.- Numerous animals, primarily wild

rodents and lagomorphs (rabbits) have been found to harbor

the disease. In addition, many of the flea species of these

animals have been found infected.

Government organizations, principally the U.S. Public

Health Service and local state health agencies,have been

following the disease for a number of years. In the last

few years the U.S. Army, due to the situation in South

Vietnam, has sponsored research on plague ecology and control.

At the present time, studies, on the basic ecological

relationships of the hosts and their fleas, and the con-

trol of these fleas, are being conducted by the New Mexico,

Environmental Improvement Agency (formerly New Mexico Health

and Social Services Department). The studies are being

financed by the U.S. Army Medical Research and Development

Command. In addition, cooperative studies on flea control,

with systemic insecticides plus certain new control approaches,





3
are being evaluated jointly by the U.S. Department of Agri-

culture, Entomology Research Division, Insects Affecting

Man and Animals Research Laboratory, Gainesville, Florida,

and the New Mexico, Environmental Improvement Agency.

The field studies were conducted in southeastern New

Mexico where known human and zootic plague had been pre-

viously recorded, (Kartman 1960). The New Mexico Environ-

mental Improvement Agency had done previous work in the

area, and had shown suitable animal and flea population were

present to conduct the type of study desired. (Rael et al.

1969).

To control any arthropod-borne disease the classic method

of breaking the transmission cycles is either at the host

or vector level. Plague is no exception to this rule. In

South Vietnam, immunization appears the most practical and

seemingly effective method. When plague is in a zootic

form such as the western U.S., this approach is not possible.

The most practical control method seems to be control of the

insect vector or the reservoir animal.

The purpose of this research was: to study the basic

biology of the wild animals and their fleas associated with

plague, and to evaluate some new control approaches for

future studies in plague control. The latter experiments

were conducted at the U.S.D.A. Laboratory in Gainesville,

Florida.













REVIEW OF THE LITERATURE


This work, though not directly involved as a plague study,

was done to provide basic background material for future

ecological studies in plague control operations. Because

of the volumous material written on all facets of plague

over the years, no attempt will be made to review the liter-

ature completely. However, a brief resume of plague, begin-

ning at a world level and terminating in areas related to

the field of study is given.

PlaPue A Brief History

Plague, according to Wu Lien-teh et al. (1936) and cited

by Pollitzer (1954), has been present since time immemorial

in the areas within or near the central Asiatic plateau.

This area is considered the original home of the infection.

Wu Lien-teh further states the first plague epidemic on

record was the outbreak among the Philistines in 1320 BC.

This is described in the Bible in I Samuel V and VI.

Pollitzer (1954)reports that some writers refute this date

due to interpretations of the Biblical text and further states

t~e first really satisfactory evidence regarding the preva-

lence of plague concerns a pandemic that occurred in Pelusium

in lower Ucypt in 542 A.D. This outbreak, which lasted

approximately sixty years, spread as far as Constantinorle

4






and killed an estimated 100 million people.

Probably the most well-known epidemic as far as modern

man's historical record is concerned was during the Middle

Ages, when the "Black Death" (plague). killed 25 million in

Europe (Herms 1961).

A more recent epidemic occurred in Hong Kong in 1894 and

spread to many world ports via shipping lanes (Pollitzer

1954). According to Herms (1961), rats, infested by rat

fleas, and transported in goods, are the chief dissemina-

tors of the disease.

From 1900 to 1952, plague was recorded in 39 countries, and

from 1945 to 1952, there were 37 cases reported from seaports

of various countries (Atlas of Plague, 1952).

Today the largest focus of plague in the world is in

South Vietnam. In 1966 there were approximately 5,000 re-

ported cases (Cavanaugh et al. 1967). Strict quarantine

measures seemed to have contained the disease in that country

(Rust et al. 1969).

Plague was first recorded in the United States from San

Francisco in 1900 (Jellison 1959). The outbreak ended in

1904, but reappeared in 1907. Other cases occurred in

Seattle in 1907, New Orleans in 1912, several Gulf coast

cities in 1920 and Los Angeles in 1924.

Pla.ue Western United States and Canada

Sylvatic, or wild rodent plague as it is called by many

workers, is endemic throughout the western United States,

and in the provinces of Alberta and Saskatchewan, Canada








(Likfiel_ d 1I2 ). Various workers have reported on plague

in the western United States. .cCoy (1910), in 1908, first

discovered plague was no longer confined to rats and rat

fleas in the United States as it had spread to the wild

rodents and their fleas in the San Francisco Bay area.

Eskey and Haas (1940) reported the primary reservoirs of

plague were ground squirrels, _Snermonhilus (Citellus) s. ;

woodrats, NeotLomnp sn. ; and prairie dogs, Cynonvs s-__.

Today, according to Kartman (1970), there are 10 rodent

and 2 lagomorpha (rabbit) genera, that include 45 species,

found important in the ecology of sylvatic plague.

In New --exico (where this field study stook place) plague

organisms have been recovered from wild rodents, rabbits,

and hares and/or their fleas, in 23 of New M!exico's 32

counties (Rael et al. 1969). Further documentation of the

study site as a potential nlague area is given by Kartman

(I960), wiho reported that two hunters contracted the disease

"' handling diseased rabbits they had shot. These cases

occurred approximately eight kilometers north of the study

site selected for this research and contains similar

+topo-r hy, flora, and fauna.

pi .I e '*^'n 'dc .oloev

Kartman (1970) lists three main situations which lead

to the rice and dissemination of plague. He states that

wars are a primary factor in the spread of the disease,

cp-ciJly the wars of the 18th and 19th centuries where

trcoon were involved as both victims and agents of dissem-







nation. Further, Kartman reports, the unusual exacerba-

tion of plague incidence in Southeast Asia, especially in

Vietnam, should be examined carefully from the epidemio-

logical standpoint as a basis for a reevaluation of the

plague problem in specific countries of the world. Another

type of epidemiological situation illustrated by Kartman

includes those endemic and enzootic regions where the great

mass of the people live in a condition of extreme poverty.

He cites the recent plague epidemics in Bolivia (1964-1965),

Nepal (1967), Java (1967-1968), and the prolonged cycle of

epidemics in southern India as examples.

His third category is that found in more affluent societies,

or in countries that have reached a stage where they can ef-

fectively organize a public health service. In these cir-

cumstances rat-borne plague tends to disappear and sporadic

plague cases are due to the occasional transmission of the

infection when people invade a nidus of sylvatic plague.

An excellent review of plague epidemiology is given by

Pollitzer (1954)1 he covers most of the significant plague

epidemiological work up to that date. The World Health

Organization (WHO) publication/Vector Control/66.217.1966

gives a more recent report on plague epidemiology, including

sections on plague associated rodents and rodent ectoparasites.

A brief, but informative survey of plague epidemiology is

made by Starke et al. (1966).

The plague situation in the United States, falls into

Kartman's third category. He states 120 human cases occurred







in the United States from 1908 to 1968, that were directly

attributed to wild rodents, rabbits, and/or their fleas.

Of these, ew r-xico has had 20 cases. Since I1'6, each

case has been well documented, either by the New I'exico

Envirorme ,ntal movement Agency, Vector Control Unit,

miller r 1971) or the U.S. Public Health Service (Kartman, 1970).

Tost-'lep Relationshins

.'iany workers have created countless publications on the

Siphonaptera. No attempt will be made to review all the lit-

erature on this subject. A general description of the

Siphonaptera is given by iIatheson (1950). Snodgrass (1946)

presents a very comprehensive review on the skeletal ana-

tomy of fleas. Probably the most complete work on Siph-

onaptera taxonomy was done by Hopkins and Rothschold (1953)

(1956) (1962). Stark (1959) presents an excellent study of
many of the western fleas in his book The Sinhona.tera of Utah.

The most complete, but rather outdated book on western fleas

was written by Hubbard (1947). WVheeler et al. (1971) have

prepared a taxonomic key to the fleas of New I.iexico and is

no-,. in manuscript. In addition, Wheeler (1968) developed a

working taxonomic key specific to the fleas of Red Bluff

Ranch, which includes all the fleas in this study, plus

other species that the New "exico Environment Improve-

ment Agency collected during their ecological and flea con-

trol studies in the area.


Various workers have studied the life history of fleas.







Bacot's (1914) classic work with Pulex irr-i.an Linneaus

remains one of the basic guides to life history studies.

i..ost of the research in flea biology has been done with

Xenonpsvl cheopis, Rothschild. This is due to its associa-

tion with plague and, in addition, it is one of the easier

fleas to rear in the laboratory. This species was used for

all the laboratory work done in this study. Most of the

following comments deal with X. cheonis. Note will be

made if any other species are involved.

Buxton (1948) concluded the adult flea could survive at

temperatures from 24-320C and the life cycle of the flea

will vary according to the temperature and humidity.

Hopkins (1935) reported that the life cycle could be com-

pleted in about 56-63 days, the minimum being 42 days, at

a temperature of 200C and a relative humidity of 100 percent.

Krishnamarthy at al. (1963) found that at a temperature between

25-280C, and a relative humidity between 75-80 percent, the

life cycle could be completed in 24-29 days. Studies made

by Burroughs (1953) indicated that six species of fleas in-

festing rodents in the western United States had maximal

periods of survival comparable to X. cheopns.

Repri n

Fleas utilized in the laboratory portion of the study
were provided by the U.S. Department of Agriculture, Insects

Affecting Man Branch and Animals Branch, Gainesville, Florida.

They were reared by the technique described by Cole ct al.

(1972). No fleas from the study area in New Mexico were

reared.







Flen Rletion shiDns

Numierous workers have collected fleas and their host for

taxonomic or distribution studies; Hirst (1923) was the first

to study the relationships between the flea and the host.

He demonstrated that in addition to X. cheomis, two other

Xenonsvlla s-.-n, namely X. asti. Rothschild and X. brasi-,-

iensis (Baker) were present on the rats he collected. It

led the way for further work on plague-vector studies.

Taylor and Chitre (1923), as cited by Pollitzer (1954), con-

firmed Hirst's findings and showed that although X. astia

is capable of becoming blacked and transmitting plague, it

is a markedly less efficient vector than X. cheopis or X.

brasiliensis.

F3e Surveys

Before appreciating the influence exerted on the trans-

mission of plague by variations in the incidence of the

vector fleas, it is necessary to consider the methods re-

commended for flea surveys.

Cole and Koepke (1947) give an excellent guide for all

workers to follow. It states:

1. Indices commuted from total fleas are unreliable
because they are apt to include non-vectors, as
well as species which are unequally effective as
vectors.

2. The time fleas of different species spend on
their hosts is apt to vary considerably.

3. No reliable measurements of the absolute number
of the fl.ess can be made without considering the
number of rodents because "a decreasing host npou-
lation will reduce the average counts".







I;. 'Te host species ou ht to be uniform in compared
sa'7l~s because, as in the case of R. nare.'-ies .nd
3. --+ts -, for instance, di.rfrent rodent-srecics show
c *'fren2ces in flea infestation.

5. T2he a.'e, as well as the size, of the individuals
affects the counts, young and old rodents being liable
to heavy, infestation. The same may hold true of un-
healthy animals.

6. Trapping techniques must be consistent in order to
obtain comparable data.

7. Widely different indices may be obtained from
rodents trapped in different sections of a tovwn, or
in different locations within one particular neigh-
bourhood, or even on different levels of one building.
X. choo.is, for instance, particularly infests rats
in grain stores, and is markedly more abundant on
rodents trapped. inside buildings than on those caught
outdoors.

8. Fleas do not uniformly infest all rodents of a
locality, but show a patchy distribution so that,
sometimes, a large part of a flea population is con-
centrated on a few animals.

Other workers (Pollitzer 1954) believed that instead of

indices, more reliable results can be obtained in flea surveys

by computing the percentage incidence of the various species

or the infestation rates, i.e., the percentages of rodents

infested with the various flea species.

Workers such as 'Macchiavello (1950) have recommended that

the total or "absolute" flea index should be determined by

considering the results of examination of the burrows and.

nests, as well as those of surveys carried out in the usual

manner. He recommends the application of the formula:

AFI RF + NF when AFI stands for the absolute flea index,
TR
RP for the total flea population living on the rodents, NF

for the absolute number of fleas from flea breeding or flea








harborage, and fR for the total rat ponmulation of the area

concerned.

Pollitzer (1954) states that desirable as determina-

tions of the absolute flea indices by this or other methods

are, it seems difficult if not impossible to make routine

use of such procedures.

A recent study (Uitchell 1971) in India, utilizes the

graphic method of comparing flea indices with total number

of animals infested. Though not as accurate as some formulas

presented by earlier workers, it appears to be a practical

and relatively simple method of showing trends in host-flea

relationshiDs.

In New MIexico, Rael et al. (1969), using an ecological

approach to host-flea relationships, discuss these assoc-

iations by frequency of fleas on a particular host and per-

cent occurrence of the flea on the host.

There is no one-and-only guide that can be given to the

study of the host-flea relationships of plague. What might

work in one area may not be feasible or practical in another

area. Kartman (1970) ably describes the status of this

work in the United States by stating:

It is important to indicate that oecolo.ical studies
of mammals involved in plague in the United States
have only scratched the surface of that formidable
epizootieolocic complex represented by the phrase
"wild rodent placgue". Vie need intensive and long-
term studies of mammalian oecology specifically within
the environs of plague localizations or nidi.






Animal Relationships

Identification--Hall and Kelson (1959) present one of the

best reviews of mammalogy available for definitive taxonomic

work. An earlier, but valuable book for the student of

mammal taxonomy is a check list of North American Mammals

by Miller and Rahn (1901). For the basic identification

of mammals needed for this study a field guide by Burt and

Grossenheider (1964) was found adequate.

Ecol Qgy--One of the primary objectives of this work was

to study the host-flea relationships of the animals on the

study site. An excellent presentation of desert animals by

Miller and Stebbins (1964) gave an insight into the habits

of the animals under scrutiny.

Microclimate--Kennerly (1964) conducted a study on the

microenvironment of pocket gophers, and tested some instru-

mentation not before used by the field ecologists. Haas

(1965) did a similar study but created artificial burrows

for his work. Another paper dealing with microclimates

was done by Mitchell (1971). He simulated burrows of

Bandicota benJaleensis in India. His work, though well

documented, seems to conflict with results of earlier workers.

Populations--One of the most widely utilized techniques

for determining animals populations was devised by Schnabel

(1938). In studies that have large numbers of captures and
recaptures the method is very accurate but when small num-

bers of recaptures occur, it results in a large standard

error. Wildlife workers have devised numerous census







methods for estimating animal populations. Many of these

are discussed by Mosby (1963). A number of these techni-

ques are statistically feasible but have such large con-

fidence limits they are not practical.

Laboratory Studies

Numerous papers have been published on various aspects of

flea control. Because this paper deals with just one method,

control through the systemic route, only brief mention will

be made of the more conventional techniques.

Metcalf et al. (1962) and Herms (1961) give basic flea

control procedures including recommendations of insect-

icides to use. Pollitzer (1954). gives an excellent summary

of flea control as applied to plague control operations.

Most of his recommendations deal with DDT, which has now

been replaced by newer materials. A list of insecticides

effective against the oriental rat flea is given by

Burden (1966).

Most of the work to date has been done on domestic ro-

dents and their fleas. A few papers have been presented on

control of fleas on field rodents. Ryckman et al. (1953)

evaluated four compounds including DDT for control of wild

rodent fleas of the California ground squirrel. All the

compounds were found effective in laboratory tests (Smith

1951). Ryckman also tested various application methods,

including. spraying the surface, dusting the surface and

spraying individual burrows. Of these applications only the

latter produced significant reductions in flea indices.






Miles and Wilcomb (1953) working in west Texas with DDT

found that the broadcast method of application was not

effective in reducing flea populations on pack rats

(Neotoma micropus Baird). Miller et al. (1970) working on

the New Mexico ranch site used in this dissertation eval-

uated five insecticides under field conditions. None of the

chemicals gave satisfactory control though two of the chemi-

cals showed some initial reduction in flea indices. All the

materials had been shown effective in laboratory screening

tests (Burden 1966). The problem of successfully controlling

fleas on wild rodents and lagomorphs seems to be a problem

of application method rather than effective insecticide.

A new approach to this application problem has taken the

form of systemic insecticides. This concept, though new as

far as the flea control on wild animals is concerned, has

been around for a number of years. Parman et al. (1928)

administered unsuccessfully, oral doses of chemical com-

pounds to poultry to determine systemic insecticidal activity.

One of the first successful attempts at systemic control

was reported by Lindquist et al. (1944) who showed that the

bed bug, Cimax lecturlarius L., could be killed when fed on

rabbits that had. been given oral doses of DDT and pyrethrum.

DeMeillen (1946) found that the bed bug, the yellow-fever

mosquito, Aedes aeggpti (L.), and a tick, Ornithodoros

mpoubata (Murray), either died or showed toxic effects after

feeding on rabbits that had been fed BHC. Knipling et al.

(1948) fed 33 chemicals to rabbits to test their effectiveness






on bed bugs. Only indandione compounds caused complete mort-

ality. Eddy et al. (1954) demonstrated that populations of

the yellow-fever mosquito, the stable fly, Stomnoxvs

calcitrpr (L.), and the horn fly, Haematobia irritans (L.)

were reduced when allowed to feed upon cattle receiving

lindane. Larvae of the stable fly, horn fly, and house fly

7u1sca domestic (L.), were killed in the droppings of live-

stock fed aldrin and dieldrin. Adkins et al. (1955) found

Trichlorofon to be the best of 13 compounds for bed bugs and

nymphs of the lone star tick, Amblvomma americanum (L.).

Drummond (1958) found three organic phosphorous compounds to

be effective against screwworms on sheep and goats, and one

effective against stable flies and ticks. Systemic insect-

icides have been widely used for control of cattle grubs,

Hvooderma Jineatum (de Villers) and H. bovis (L.) Harvey

(1960) tested the systemic activity of several compounds

against the oriental rat flea, Xenopsvlla cheopis (Rothschild).

In small scale experiments, Bennington (1960) found that 6 g

of ronnel-cornmeal mixture killed all fleas in 3 days. Hill

et al. (1963) evaluated 21 compounds for systemic activity

for control of the oriental rat flea on white rats. None

of the 21 compounds produced more than 50 percent mortality

of the fleas. Five compounds were considered worthy of more

extensive study. All these compounds caused 80 to 100 percent

mortality up to twenty hours.

Clark and Cole (1968) found that four systemic insecticides

incorporated into the diet of hooded white rats produced 100






17
percent mortality in the oriental rat flea. Further work

by Clark et al. (1971) showed that three insecticides,

fenthion, mirex, and diazinon, successfully controled wild

caught fleas of cotton rats, SiJ-odon hisjidus (Baird),

Kangaroo rats, Dinodomio s snectabil.is Ierriam, and the

cottontail rabbit, STlviiZllau audubonj Nelson. Present

studies are underway to further test the applicability of

systemic insecticide baits to control wild animals fleas.












MATERIAL AND METHODS


Location and Descrintion of Field Study Area

A permanent study site was established at Red Bluff Ranch,

a cattle ranch located approximately 48 km north of Roswell,

New Mexico. This region lies within the lower Sonoran life

zone (desert biome) at an elevation approximately 1158-

1239 m. A series of bluffs from where the name Red Bluff

originated, transects the western quarter of the ranch from

north to south. The bluffs divide the ranch into a western

and eastern plain, the latter sloping into the Pecos river.

The southeastern section of the ranch contains several,

usually dry, lake beds. The location of the study site was

in the southeastern section of the ranch. The area was

chosen because it typified the flora and fauna of the ranch.

Climate--The climate is semi-arid in nature. The average

minimum, 6.70C, occurs in late December or early January.

The average mean temperature is 150C. Total annual precip-

itation is 29.4 cm, over half (17.8cm-21.6 cm) occurs as

rainfall from June through September. Though snow occurs

in the winter season, little precipitation of any kind norm-

ally occurs from January through April.

Flor~--The ranch has several flora. associations.

These are influenced somewhat by topography and overgrazing.

18







Mesquite, Prosois uliflora Wats, is dominant on most of

the valley floors and slopes while the creosote brush,

Larrea tridentata Vail, occurs on many of the ridges. The

predominant tree on the ranch is salt cedar, Tamarix

gallica Linneaeus; this occurs only along natural drainages

and in dry lake beds. Predominant grasses are Boutelroua _.

and Hilaria sD. These comprise the main diet of the cattle

grazing on the ranch.

Fanna--Numerous rodent species abound throughout the

ranch. Eight species were collected on the study site

itself. These will be named in the next section. Rabbits

(Lagomorpha), are abundant in the area and include the

black-tailed jackrabbit, Lenus californicus Gray, and the

desert cottontail, Sylvilagus audubonii (Baird).

Carnivores inhabiting the area include the coyote, Canis

latrans Say; gray fox, Urocvon cinereoargenteus (Schreber);

kit fox, Vulpes velox (Say); striped skunk, Menh'itis

menhitis (Shaw); badger, Taxidea taxus (Schreber); and the

bobcat, Lvnx rufus (Guldenstaedt).

Predatory birds abundant in the winter are the marsh

hawk, Circus cvaneus (Linnaeus), and red-tailed hawk,

BIeIo jamaicensis Bangs. In the summer months the burrow-

ing owl, Sneotyto cunicularia Ridgway, and Swainson's hawk,

Buteo swainsoni Bonaparte, are common. The most common

reptile that inhabits the area is the western diamondback

rattlesnake, Crotalus atrox Baird and Girard; other snakes

observed, include the prairie rattlesnake, Crotalus yirJcid







(Rafinesque), the coachwhip, WMasticophis flaellus Shaw;

the bullsnake, Pituonhis catenifer (Daudin); and the hog-

nosed snake, Heterodon nasicus Baird and Girard.

Other than the ranch cattlethe hoofed animals present.

include the pronghorn antelope, Antilocapra americanum

(Ord) and the mule deer, Odocoileus hemionus (Rafinesque).

Selection and preparation of study site

Prior to selection of the permanent study site, a number

of locations were surveyed to determine if a suitable

animal population, both in numbers and species, existed.

An arbitrary figure of 40 percent trapping success for

three trap nights was set as a criterionr The various

locations were trapped, using 25 National (Tomahawk Trap

Company, Tomahawk, Wisconsin) and 25 Sherman trap (Sherman

Live Traps, Deland, Florida). The traps were placed in a

straight line and spaced approximately 6-12 m apart. One

National and one Sherman trap were placed at each trap

station (location). Each station was marked with a stake

to insure all traps could be located the following morning.

Traps were placed in the areas during the late afternoon

and baited with a mixture of 2 parts milo and cracked corn

to one part rolled oats. The traps were checked at approx-

imately sunrise the following morning. Total animals trapped,

and their identification were recorded then they were re-

leased at their site of capture.

Of 10 areas sampled, three had met the criteria as far

as animal population was concerned. One location was elim-







inated because no creosote brush was present. A second

location though an excellent area, was dropped for pre-

ference to the selected site. The study site was chosen

for the following reasons: contained suitable animal pop-

ulation (above 40 percent trap success); vegetative types

were of the types desired (creosote-mesquite association);

ease of access by vehicle; and. little grazing by the ranch

cattle.

Preparation and tra ingof ogrid

The trap grid was established by placing .91 m, wooden

stakes 6 m apart. One National and one Sherman trap were

placed at each stake (Figure 1). Two different types of

traps were utilized, to determine animal preference, if

any; and. to compensate for the large or small size of the

various animals to be trapped. Stakes and traps were

numbered in sequence 1-100. The study grid was 114 m x

24 m, or 2736 sq m (approximately 0.28 hectare).

The study area was trapped one time per week, usually

Wednesday, unless adverse weather or some other unforeseen

happening occurred. It was felt additional weekly trapping

might have reduced flea and/or animal populations and given

false indices.

Once the grid was established and weekly trapping began

the following procedures were done. Traps were baited as

previously described, in the late afternoon. It was neces-

sary to be at the study area at sunrise the following morn-

ing to pick up the animals for the hot desert sun caused






22


























asla






















Fire 1. Traps at stake site.





23
mortality very quickly. The animals were picked up at their

respective capture sites, and taken to a processing area

(Figure 2). Upon completion of processing they were re-

turned to the same stake site and released.

Animal Processin.~

Each individual was processed separately. A detailed

data sheet was maintained on each animal (Figure 3). The

processing procedure occurred as follows: The animal was

taken from the trap with heavy duty welder's gloves, placed

in a large, white enamal bucket (slop jar), a transparent

glass lid was quickly fitted, on the top. The animal was

anesthetized by slightly tilting the lid and spraying

ether into the bucket from an aerosol can. Fleas were

then removed from the animal by brushing it with a tooth-

brush over the bucket. The fleas were collected from the

bucket with a small camel-hair, artist's brush and placed

in a vial containing 70 percent ethanol. Labels, contain-

ing date, animal number (which identified its location to

a particular data sheet) and contents were placed, in each

vial. Fleas were later identified in the laboratory using

Wheeler's Key to the Sinhonanter_. of Ped Ibiff Ranch on

Rodn-ts. Rabbit.t H-re, arid CrnWivores (1968). The field

exnedient method used to identify the fleas is described

by Stark (1959).

The animal was then weighed and measured and deter'i-

nation of age and sex made. The animals were weighed eh.ch

time they were trapped but were not remearured 'nicrn ',he-







24


























0
o







*H


0
o
















H


C)



Nl









SHEET NUMBER

INDIVIDUAL ANIMAL DATA SHEET NEW MEXICO PLAGUE PROJECT


1.
4.
5.
6.
Me
7.
8.
9.
10.
11.
12.
13.


Species 2. Se
Toe Clip Number
Date Trapped
Trap No. and Type
asurements:
Weight
Total Length
Tail Length
Ear Length
Hind Foot
Anal Temperature
Fleas (including sex)
M F
(1)
(2)
(3)
(4)
(5)


x 3. Age


M F F M F M


14. Total Fleas
15. Other Ectoparasites


16. Observations:








Figure 3. Individual animal data sheet.


F M F







wee. i-atu es when first trapped. Nert, using a tele-

t -no' et~ (Fi.mire L-) the ani-als anal tem ~r'c.-re was

tae nn. Ienti ~_iions of tle animals wee usin.

Burt and -rossenheider's text "A Field Gudre to the R^.nals."

After identificati'. the animals were toe-clinped as des-

scribed ; ai (101) then ta en back to their capture site

and enlcped". All data listed on Figure 3 wss completed

weekly except the above "mentioned items.

Aft-er all individual animal sheets were completed for a

-.:eek's trappning, a weekly data sheet was compiled (Figure 5).

Continuous above rc..r' temperature and humidity readings

were taern with a hydrothermograph. Underground burrow

readings were r-de once a week. These readings were ac-

com -is ed by insertingr a hcllow, hard-rubber pipe, approx-

i-ately two inches in diameter down into a burrow' area.

T- rro'w was determined active by lowering a piece of

7 1 on a string down the pipe into the burrow The bait

wld be eaten if an asir-al were present. Once an active

'O.rrow .c found, read n-.7 were made with a hydrothermometer

( ,o"l 1 -303( Will Scientific Co.). ""'.is instrument was

e"i :d ith ?.3 Icadr which attach to sensor devices.

ors were lowered into the burrow. and the ter'ncra-

hu ":i>-ditr '',ere measurer b- the instrumi.ent above

cnd .nd and a.in all ere eas rred with instruments

frc ? U.S. Air Force weather kit.

f-e ollovwin proceCdures were done to supnlement the

re nata frori the sPtAcr Cite:























C-1





S)
c


















C)


C)
4-:

0






C
C);










ECOLOGICAL SURVEY SHEET NEW MEXICO PLAGUE PROJECT

1. Location 2. Date
3. Number of Traps (a) N 4. Number Animals Trapped
(b)S

5. Percent Trapped 6. Pick up time
Weather Conditions: 7. Wind (MPH) 8. Sky
9. Moon 10. Rainfall 11. Soil Cond.
Temperature: Constant Recording, Above Ground
12. Min. 13. Max. 14. Aver.
Single Reading, Below Ground 15.
Humidity: Constant Recording, Above Ground
16. Min. 17. Max. 18. Aver.
Single Reading, Below Ground 19.
An imal-Ectoparasite Data:
20. Species Collected (Taken from Individual Animal Sheets):

Ectoparasite Data
Animal Species Fleas Flea Index Other Ectoparasites

1.
2.
3.

5.
5-
6. Total Animals 7. Total Fleas
8. Total Flea Index 9. Total Other
10. Animals Collected for First Time
11. Collected Previously
12. Observations:


Figure 5. Weekly summary data sheet.







1. An estimate of' the population of the study area

,was made by using the Schnabel population estimate

(Schnabel 1938).

2. Routine trapping was done in adjacent areas of the

ranch to collect animals to make study skins of the repre-

sentative animals in the study site without disturbing the

population on the site. Study skins were prepared as de-

scribed by Anthony (1950).

3. To determine if the plague was present in the

animal population in or around the study site routine blood

and/or tissue (spleen) samples were taken and sent to the

New Mexico, Environmental Improvement Agency, for laboratory

work-up. Animals from the site were not utilized, unless

they had died during processing (too much ether, etc.).

Laboratory Stud ie s

This portion of the study was conducted at the U.S.

Decprtment of Agriculture's (U.S.D.A.), Insects Affecting

Man and Animals Laboratory, Gainesville, Florida.

Fleas used in the tests were reared by the above labora-

tory as described by Cole et al. (1972), four-to-seven-day-

old fleas were utilized for the tests. All were XenprDyvlla

nheooni, the oriental rat flea.

The rats used for the tests were from two sources.

Hooded rats (cross between the wild Norway rat and the

domestic white, laboratory rat) obtained from the U.S.D.A's








Laboratory animal colony, and wild, roof rats Rattus rattus

Fischer, which were live trapped from the University of

Florida's Poultry Research Unit located adjacent to the

U.S.D.A. Laboratory. The traps utilized were National

(Tomahawk) foldable, wire traps (3.3 x 5.0 x 8.3 cm). The

traps were baited with apple in the afternoon and the rats

picked up the following morning. No data on trap success,

numbers collected, etc. as with the field study, were main-

tained. These rats were trapped for test purposes only. The

rats were checked for fleas as described in the field study

but this was only to insure no other species or wild strains

of Xenonsvlla cheopis were introduced into the colony cages.

Once the rats were checked for fleas (none were found)

they were placed in a large colony holding cage, 3.6 x 5.5 x

7.3 m (Figure 6). The cage was made rat-proof by completely

lining the inside, excluding the plywood ceiling, with .6 cm

hardware cloth. This prevented the rats from chewing through

the wood and escaping. The cage was sunk into the ground

approximately 30.5 cm deep, white sand was placed inside the

cage to provide a burrowing medium for the rats. In addition

cardboard boxes of various sizes were placed inside to pro-

vide harborage. Standard laboratory rat chow (Purina-

Ralston Company) and water were provided continuously.

lMethods and Procedures--The literature produced no guide

for the methods used in this research. Many studies on the

effectiveness of various animal systemic insecticides have


















wILlP













Clarkn and Cole (1 58) evaluated. a number of insecticides

for systeoic action in rats for flea control. Of these,

fenthion (0,O-dine-'-'"l o-0I-( ethylthio)-m-tolylm phos-

phorothicate) was one of the more successful materials. Fr-

ther evidence of this insecticide's potential as a "stem:ic was

demonstrated by Clark et ale (1971). In this case it was shown

effective against some of the fleas on field, rodents and cotton-

tail rabbits in "ew Aexico. From these data it was decided tc

-se fenthion as the insecticide of choice for these tests

Initial tests were conducted to determine if sticWk

n" trials such as vacuum grease or vaseline (petrolc,'m

jelly) could be used as a carrier for an insecticide such

as fenthion. The first tests were conducted with vacuum

grease but it was not as acceptable to the rats and later

dropped and vaseline used exclusively. Solutions containing

1, 3, and 5 percent fenthion in hexane were thoroughly mixed

with the carrier. During these first tests the )0' ia]

,--R '.re on the front "cct of R.

O1 r'nco~s too!: clace as follow. A single r .:...


te-ed with chloroform and cc'bed to insure no fleas wre-

tized wvith chloroform and co-ibed Ito io n suire no flcas ,:%ere

-"" ',3 -e :***" ;.o :- t`c "" c i l "^ *'. "" *-- '






r in 0T *-1 -% N


.'hre -6 at '.,:.s orovided 4 v "/ge r and '^e c 'ri- 2' .-^'rc

At this time 100 fleas from the U.S.D.A.'s colony e.,'re

nl-ced in the cont 'in'r. M"'o renetitio- e oech core

tration- nr 2 checks Vere r'~u concurreti;L, t rat' -'"r

checked dCily for fleas and 100 fleas w:cre added per da

for one week.

Once results indicated the material vould kill the fleas

present further tests 'were initiated. Artificial rat runs

(Fgurre P) with removable centers were made to si'r.te a

rat's movement under field conditions, At first the sticky

material was -laced on the removable center and it w- rnea

to its original position. This was found unsuccessful.

I;ext the material was placed on both sides of the center

and a bait (non-treated) was placed in the center hole.

This was to attract the rat into the center and thereby

cause it to walk across the treated material. Thic. method

was only partially successful. The only way to insure the

rat would pick up enough material to effectively redce the

flto fer' it ,,' t



7- t 1A r3 _T ... C.' < J .'". ".



practical control me tho1 T;ar fea i bo ore.-

'he la.t ro'Un of tests C inC r. .-
















































C




0
?-1



c





*-











.-j


c-
















^


i..































































































Ci






o.












r ats weeCere T -

i'n the runs as sTreviously described. -' rats were nrovid-

i '-;ith v.-ate but their only food source (.apole) w.as -..ithin

thc artificial rat run,' Tis vas a last attempt to see if

this techni.ie -"-:-t have any practical value -e rats

fed on the aT-le but no significant reduction was noted in

t>e fleas on the rats. It therefore, became apparent that

this method in its present form was not a successful method

of flea control by the systemic route, Further discussion

on the future feasibility of this technique and closely re-

1 ted methods are included in the next section.












RESULTS AND DISCUSSION


Field Studies


Discussion of Asnects Relatine to the Study Site

No plague infected animals were found on the research

plot or any part of Red Bluff Ranch during the months of

study. 'As previously stated, Kartman (1960) reported plague

from 2 human cases and a rabbit epizootic approximately 8 km

north of the study area.

An initial objective of the project was to find a plague-

free area, have a natural epizootic occur, then follo-,: the

outbreak through the animal population, studying the ecolog-

ical relationships of the disease to the infected and unin-

fected animals and their fleas.

A study of this nature was done by Lechleitner et al.

(1962) in Colorado, using a colony of prairie dogs, Cyn-Ojm

nm.nsonii ,runnisjni (Baird), as study animals. They had

initiated a basic study of the prairie dog colony without

any knowledge of the oncoming plague epizootic.

The epizootic when it did occur, swept through the colony

and killed every prairie dog in the area of observation so

quickly it limited the amount of data they could, collect on

the movement of the epizootic.







A--er the epizootic began the workers started collection

.. .. .. o er animal .:iees "a i tCrea,'
S.~r:n-Tzls -resent t'hat h eer .. previo-J :Iy eounjC infected ,,v"-t

plague ( "rtman 1070) included, the deer mouse, F"'i'-.-.

-'" 1 'i..-.' (' ner); golden-mantled -rou-d squirrel,

r,- o'. (Ctej s) Lateralia (Say); mountain pocket

gooher, 7- q oe'.?, s (Richardson); and Richardson's

-""d squirrel, S-r .'.~C- (CJtellus.) ci:-o-arm--- (Sabine).

Apparently none of the animals except Richardson's ground

squirrel were affected by the disease. This species was

affected only in the immediate area of the prairie dog

colony and those, even in this area, were not affected if

they had entered their summer dormancy period.

No opportunity arose for such a study at Red Bluff Ranch

but future studies in plague ecology will have to include

this work if the host-flea relationships, prior to, during

and after a plague epizootic are to be known.
" rI .. ... .1 ~ P -,I 1 t

Trapping on the study plot began March 13, 1968 and

continued through July 16, 1968. A total of 17 trap nights

res lted in the capture of 306 animals, and represented 903

captures and recaptures. A summary of trapping results is

given in -'rble 1. After the first week of trapping, percent

trapping success was fairly constant. A general increase in

recs''-'" rates occurred throughout most of the trapping

period. The last 2 trap nights were lower but this was due


















H
H


0M
o



o co


r:
- 0
Cl) e


O S
-P

O *



C.)
re o








Co -

1 0


*E
o

O ^
H \C



O


4- 0 *\
0 0





HHH
Q) 3O0
C) H
: C \0






*Hl b











Sd
OE 4 O


(U
Q)D








-P)
0
So

00
















C)








4 3
-p



4




0)
c4












00
















0) ?





-r^
ed
S -


O -l Hr H \C C-
















V H \ \-l H \O c\
0 ri N N -(%














(%\ Hi H-I - .:- C 0- O0 C-CD
Hr- N N N N N N N














\0 H -i H-I -j-- co -:J- \Q
N ~ ~ -_ _j V









H N- H H CO
r- \0 H

*j *d r P 4 P 4 <
;Z ZE < < < < 2 2


C
O

C


4-
o







cl)





















\0 0- C C- O \0
0O 0 ,0 0 CO 0 \0


Co co \ c\ O r-i 0
;f -;f -^* -d i^- c7 r^


CM
0 C
) 3 -- cr CN C\ cn C\ -N,- c













r-q


0 0 \0 \0 C- O O -


co COo ,\ q
S 0 0 >
C) C C C >
Ct C i l- -
- *- H Z Z H


C'z


4-D


f V
"c



-C

*H











0

C)
0
Uo





ft
C


o
d

f^







to excessive rains that occurred the first week in July

(12.7 cm in one week, nearly one-half the avera,-e total

for an entire year).

High recapture rates were recorded throughout the tests.

Stark and Miles (1962) had similar trapping success with the

California meadow mouse, MiNcrotus cq2i5nin cus (Peale) during

a plague study in the San Francisco Bay area of California.

These high recapture rates are unusual. Data presented "

Mosby (1963), including numerous animal species, showed

very low recapture rates, usually less than 10 percent.

This high recapture rate, according to "osby (1963),

gives accurate population estimates when the Schnabel

(1938) method of population estimates is used.

Population Estimate--The population estimate for this

study was made from the animals captured and/or recaptured

from the first through the fifth trap nights. It was thought

use of further trap night data would cause an overestimate

of the population. This was due to i:rm--ration into the

study plot of animals from adjacent locations. Results of

the estimate are given in Table 2. When ave -.: ed, the dc+t

indicated an estimated population of 100 animals on the

24 x 114 m study plot.
_r_ o .'"ef" ef ,e c e

To insure the maximum efficiency in tra-wln animals

one should use the trap or traps best suited for the study.

Rael et al. (1969) had demont,,t ted that ationrl ( nnh'<)

and Sher'~an traos were efficient in trar'in- s'ill ;-













C)
4P
ao





Mo





'2 0


4-D
0






r-







rH
0




O


C,



0
e
















ro


r o
C






Poc


o \0 Co NCo --
C\o C- ON







\O \O 0 CN (I




C\ H H Ol CM




cM -- i- -a -


C CO 0


H H

CS r
0 0 *ri* r-


o \o
\O0
0
rH





0 \0

0
r-q


0 r- OC 0\ r-4

0 H

S 0 CO 0 00










Cr r-
rH c C CQ CQ


I

0 C
t0 0













C--C
-- 0
E -?-


< ^





-. b


'-X3
*- 0


O0


C







0

I c-








CO
- '-4


0
-I
4-1

r-


0
o





CS
r-




-P
d






-1








0
0,
.-11



















ON
H
o








0
-,

v
aP








L:


,0










:o the tranP.,^ -" '"1ciency of' C

be nrior to the stud 1io ever, it s .oi n; a 0n_

Perog:nathus sDP. would slip throt'-h the wire sides of te

National trap, and that the small Sheran trap would not

trap a rabbit-size animal. This made it necessary to use

both traps at all stations on the study plot,

A comparison of the trapping success of the two tra-

was made and is found in Table 3. Tt was apparent tha

aninmal size (as described above) was one of the dominating,

factors in determining trap success., 'o-.vr' -. fe--j,

Baird, was caught entirely in the smaller Sherman traps,

while the larger animals, such as S-or',nhij (Ci ell"j)

:Siloasrma Bennett, and Svlvilus audubon i (Baird) .ere

all trapped in National traps. Peromvasc., le igns..

(c.finescue), and OrnyQch le.uc a C.teor ('i'ed), both sll

animals, were trapped well in both traps.

^ey'l" '.earns and .) oej j Woodhcuse, .re aPr- .-oxa.Tal

t?'e ,,!'e size animals but the latter showed, definite

preference to the National trap (21 percent d:^fere-~ce

. bi-Jb l'..erriaem and M_: rus "-d':d were

nearly all (96 and 98 percent respectively) tranod in

]'1ti.7 tra -" i.opSby (17963) ta.o. ocn-resh trans ir erc,

efficiency for trappin. mot

carried out on currents of air- In addition, :oct -i

will enter .t-a s more -re~ i .. cp.. ' ."" .















\ -C \o Cc C



\C C- \0 COc0 0




V- ) cr N) \C N CC)


cc -:- \0 0
co ;j -- 1- I o o
r-- r- - 03T-


C-




C j




o



*- -



C







C^







C '
O >


0 o










0 C
-r-i
c i






2--%

o > :
? """

'3 J


\0 T- T- 0 0 0
--1 C'\ T- -


\0 cO 0 N 0 -



- C) T f o
o'i o^ c
h q '.y-.q*


SV' T- \ c\ 0 r--l T -
cH \ r '-I 0- -r


n O N -I 0\ 0
XC C'- CM) CM)


C r-l 0 --I \0 N


C\ .- CO u 0 0 0



\0 0 0 0 0


0N O0 r,, C c C 0
%-l T--i


rl



S7 4-C r-

* C


C i


C-


S 11


CC


0 0


0 P',


0


T-l


S-r

C)
.7-
Cp

4-

P"


c
..I
r,
'4_1 L"
ICL
r~C1
cc


o o


o 0


0o 0



0 0
--






0 0







o
i



0 0 j



01 try
i O


r--4*

. .



t-
17 2:


C\j CO) 0 0 0 0
CC) I *-


C-


c







-nd -eCr ou t5e- other, This :i t.he cC se C v! -....... j -~"

cut~ Sncrr-7ar: traps he'ne solid Jdes acoli -71dd --l:-? eCr

t'.c ,rean.s.. and si ? T seemed "to oe the on.,ly l ..... c... eter... ir-

ing trap efficiency during this study.

AnimpK-_ S ecies T'~raed.

Nine species of animals were collected on the stu'"- site-

Of these, eight were rodents and one was a Lagcnorph (Rabit).

The taxonomic classification of these animals is listed

below. Classification follows that of Hall and "lson (1959).

Order: Lagomorpha

Family: Leporidae

Sylvilaus audubonji. (Baird)

Order: Rodentia

Family: Sciuridae

Snermohnbilus (Citellus) l'ey?- Sen-nett

Family: Heteromyidae

PerQ.Fngtbu.s fla.ais Baird

Din~odomys ordii Woodhouse

Dpo my_ a Merii Mearns

Srn,,r nr)r"-, s_ ectab_ llj i iveerriam

Family: Cricetidae

Peromvscus le co r7 (Rafinesque)

OvCnhalmy.. P ,In--",tr (Wied)

Oe0+-!-v. mio -s Baird

The relative abundance cf the different species is -iven

in Table 4, incl'-ded also, are c-ir-on n-"mos














Table 4. Relative abundance of animals c."-.,t during
17 trap ni-',ts from March 13 through July 16,
lr~8 on Red Bluff Ranch, New ;;:..o


Total Percent of
Animal species caught all species


Dipo dOmVS. ""^.^ 92 30.0

D. pordj 61 19.9

Pe- J ,-_s lavas 36 11.8

-"..'l 1 le nL s 28 9.1

f tej- s2as~i. 23 7.6

'' sectabiAs 21 6.9

S-r.-r.-_'t.1 '. (Citellus) rjiL,- -,. 20 6.5

S 1IS. J i .'..- 19 6.2

.'co- ster 6 2.0


.... V^ p.. O







^ :,,^ ^ ^. ....-......1+ -. .o .. ...."e ;.' ^ ... .?


c o; ont-51 r -bo it;J t









n --,- '1bci l.- 1-1tc. '-non fo-.nd in t -.

species in -w '.exico (el t ai ') (K2rr::,

Of the 9 animal species collected during this tu 7

have been found infected with l- ue. The literature re-

vealed no P.--' nectpbils and D. --'- v ith rlj,'e

infections.

Various workers have tried to nrme certain ani-al scies

as reservoirs of olague in the western -'.ted Stateso

Ground squirrels were incriminated as reservoirs by -'0ever

(1942). Later workers, Kar"----'i et al. (1959) and echleitner

et al. (1962), list the prairie dog as a primary reservoirs

In 1968, in Denver, Colorado, the fox squirrel, Scir"-s

nie"r, Linnaeus, was the principal animal infected by -l1- e

in this epizootic. No other animals were found positive

(Hudson et al. 1971). Eattus orvep.-cus (Erxleben), con-

sidered one of the principal plasue-associated animals in

the world (Pollitzer 1954) was collected in the share areas

as the fox squirrel but was not found infected. Stark

(1959) states licroi s'. and, and Peromnysns am were highly

plague resistant in laboratory tests in California. In

other areas these have been susceptible animals. To date

no .author haz adecquately defi 'ed the host-pl 7u-e rel tien-

chips in the United States.

Prior to initiation of t t it as thoht thr
Prior to in-itiation of this 3tud'y it .wars thou;Tht that








* ~-~, L~:` -,( 0'


-" ....... -0 0-o;;a0t ...are ac--,G.-.. e t o tL, eis ea-.e,

-e, fie treo rese--oirs o cr*nowv data -/rs nvail'crle 0o

...nir.. t r ...ra .... as relat to plue I miller and



neatrOa r""ea 1050 ( -0) the0 a-nil ,'rould expire,

S'rmer nof toese o-nd other r s.ocies collected during the

st'" died apo.rently for the above reason.

eal te atzres (anal) :ve-e taen or all animaJ

col lc.ed. T :re !as such a wide rana- of temaerat res

.itin species nd o-erlap_.-r of te oerature a-en all

sEecies that no attempt was made to correlate any of the

data to pla's- e epizootics or potential reservoir studies,

" t cbcause so little data has been publiShed on tem-era-

t'ies of .. .ll rodents or rabbits it has been included

hoer. avera- e temperature of each species by r.onth,

plur the, nir.:.... a:d minimum teronerature recorded for each

eni-al is eiven in A-pendix I-l-ble 1).



....*"e i- nov. about the life histories of thoe rodents

c'-l-'; d uri te studr in relation to la.."e 7ollitzer

(C I . ?.,. -c s '.*"e i h i e .. n o .. .. r e i e -p


S-, 1 C Z, - ; 1 e


"2r~ ~O~C~t ~Zi3C ~rD-







--.--e -;,'o of t'! s o, u Tcr: *e ."e


by direct contact or by exchange of fleas A re-k c:

of adults, animal, by sex is given in Table 5. The ~tio

of males to females is fairly equal in mcst cases,

exceptions were species that only had 1i or less total

animals trapped.

Host-Flea Relationshins

Fleas differ greatly in their host preferences and

ability to transmit plague to man or other animals. To

adequately study these relationships one must know the

species of fleas and their hosts in the study area.

During the stu.y at Red. Bluff Ranch 1,436 fleas, re-

presenting 13 species were collected. The classification

of the fleas following. the synonymy of Honkins and

Sothschild (1953) (1956), is listed below.

Order: Si'hcnoatera

Faily: Hystricho myllidae

Subf f- ily : 0e 'li



.i-,. -is I -" omvs ohls

r'^^^"*i-: ** ** ^


Subfamily:


Anomio syl inae












yC

CF- E.
C-,,-


0
-p


C

0





C)

C-)














0
cr







o
C
C)C )S















JCJ
rc2

















C\I
,-C













0 '





ti- -


cO -C r -C


O cfl O ur c. C\. CO
r r-i r- r-H


C co
^ -1 -|1
a -? ol

C
c ,




5 Qi G!


1 CC|
zcr-

C-' -
C "'


C^



j o
cU


CN CO





c

r
C.C
r_












m -
-1 "
ul M=


j u\ CI- \o -t .z. V? cf


S0\ 0 O C\ t \O H



\o i ao \ o- V 0r









CNO O O RC C o C Cn H- H


'0uQ
d`c~w

~ P C~i.


0

ct
C r


-O C,-
-A N. ,-q


Q
C



-p

C!















C,

.c
ci



C)



r

c0








-o
* H




C-P
C-3






10r-







'" _v" Cer te":-'', t1 i.'J'--.



^-*: -;./'-T-Y"- ""d. -*'*-"-. (3a---er)-
-. .. .. ..... .

qeThr^.s_ '"-' 3 cP' __T_'_>.'' Prince

S-.'.. oti (Jordan)

Family: Rhopalopsyllidae

Pol.yTerurs. g ,:r. (Fox)

Family: Pulicidae

Subfamily : Pulic inae

S-,"-j \,,-,:-o- *allinaqces (" 'stwoo )

Subfamily: S-ilopsyllinae

Donm osylLuas ttz.ci2alis a ff. is (3.7:er)

Numerous floas have been found infected with t' e l!i-e

bacillus; according to (Pollitzer 1954) and (Stark et sl,

1966) this does not necessarily nae the series -o cl -

vector of plague Certain flea species re the,: av -

ccptible to pl':I!e, others are resistant eno.'h to t'

orgn ism the t ay be yconS rs

(Raei et al. 1969). I'any workers consider the fleas vector

nr" cinc as a ,:uidc for detemin{n, Is so--'....

pla ," tr .-'.-sion. Pollitzer (1954) describes -e

for d^'tc inrir the ve-tc e' iec o rf-Crece



conide red c tnntial lae vectors. '',

one of the ost ir rtant v cto 's of Il" e in t-he ':ol














a r e ( 3cor S L er Qo-r pt i Z 3 T ep : a yect o .... .. .

-s a vec- e'fcien y of 0 l1 1 o vector e' ficienc- v -ta

c CU ^ 0 .... "F I 0 0!7 'r 1 . Q :..7-- --- r ''



COi. C. 9. . I "- t he -4 -

t fie..., has .a vector efficiency. of 0-25, No data on

ecter efficiec co'lc 'e 1 found on thie other fies species

co le. .. rin- the stu" ~- dtateca on vector efficiency

..':ere tpcen "rom St -rrk et a1. (1C0<),



One of the most used and misused tools in the study of

ie-oaa ue relationships is the flea index. Each v'orlcer

s'es to have his on n method of data presentation, usually

deer'ined '.:. .is interests and/or method of collection.

hisn research is no exception, but rather than use only

c O"r? q bcrS on c't"he oth:rr -Iy e ase oc -n

I.jc ill e tin r call total fleas and tce
""e C f pe-r uonh (' ig e ); total f s r n-iml Oh

f" 1ecntI (-rures h 10-17); anc. in lee forn first a's a

' 'X" siT ine of flee t i ndies b e t 'i o-cioe c ( inl
ori Pn = t or- c-,


n..i h.pS.t sAi r-::nd, I TT, -1b7 s -1o T- ddi j s

-)n :}'\ Pp-'-n J"""*<*--l n <*


*'.' i'?C 'l".r\"-7~r































crt


O

r4

fl


0
SoH


,-.







C2 o
to
Hc3









EC
H O



; a) o -
o r-f











S0 1
,
0
C CO
r- d









Sr-








r0


"T'uJ.aTU -cad so-eT-J oua..AV


tr 2










0 \n

Ij I &


Oc?


C \c


CC- 0


C C


'. C


C-

C)n


cC


C


C
0- 0----






J -t






OC
- r-





- 0'


O CC





c. c r
.! v'


r-- 0
*C\


CX






c '--



I -
c vv

_i 0^-





CI- 3


C-"




c

i- *E.^


(' C"
c'c
hw^ yi


C L
Oq "
o F>

0


0 v-



H






v




rC'C

cc`



o v
(M



r?\


,-i


0-vO
* '


C
























0-H
HO






C.
C'-
e-




0-0
0(-


















0C v
. --
0-



0-J-
,-




0 (T
o r-

0--~

r^(
<- v-

o----







0--

C\JCv

Lt --*

COr-


CZG





r-c

0\-v


H--
o~l


C


co-s




SCCV


CCi









Cv


o \
0 0


0.-.

(.


0


C 0 -


OC0

SC,











O c

*0-


00 C


0 -
C



0 ..I


O -




C -
0


O c

C o


d!C\J


0
oC\


a O


Cr'
C rv


r-


0 0


0 C




O C

^?


0








c 0



v
r-





0r







0











v-C


,0--
O O H

C) C).


H cC: c,' z> 1- 'L- 0-' -


C v




i-I


o

v


e




c





0








* ,,,
















SC


C)
O v
vC,0





















0C


C, r








, t "^:Cl . f--r1 ;? J- '::er e s I -n +- n

O. t'- "ten ds (- -'

c.a. seated ira hic ..11 he res,.:.lts indict.e a e"encr?.1

decrease ir indices from i-rch to July, .is woud e re

apparent if false peaks pro'dced '' a fe'i anim.ls v:it

rany fleas, e.g. Table 6, April 10, S-1.... .j'," Li

index 37.0 were not included. If interpreted by results

in Figure 16, it would appear that Sl ar _uh_____

had a sharp increase in fleas in April. .en a su--.

of v.eekly data is compiled (Table 6) and the numbers of

animals of each species collected is listed, it becc-es

apparent that a very few animals can have a tremendous

influence on total flea indices. Data presented .raph-

ically, especially over extended periods of time does

show definite trends in flea nooulations. These variations

are probably related to monthly and. yearly climatic con-

ditions (Pollitzer 1954). "'' w :.exico, Enviro-:ent-

IPnrovem-ent Agency, has provided unpublisheod data n c f

indices from their continued study on Red Bluff T c

Th i- r-,lterial is rivcn in Anpcndix IT, Filres 2'-3

The rldta is included for comparison to the indices on



,** \ c i~ c -' l r

ac '< 4 -'.' 7 -, 1'^ s 4,"'i ''bon. e fo'YVF e : c: p -" 1"'," , -C I,
'.,;.-I ^0 ~ -- 0 n t T ri -*'i- '" i- v-l;r



















co


I-S





co



C



C







co


0

C



o 0




r-l
r---










Os -


0 \0'--
0O
^ ** -
r-O i


0-'



Of----

0-
o ,


0- 0-\


0
o

o-0 \-r;


I?


-t


0 -


0
0L


C

















C--
1
C a







*: o

o
Ci























-C-"
r -f ..


-f r






C,;
C'-" -












s.nilosoma throughout the stdy nerio6 .-.3 total -le-7

index represented by Figure 9 shows indices of 1.5 t-

3-5 -er .ni~al. This aemonstrates the need for inr'-

vid',"' indices for fleas and their host. In a -lao .

endanic area it is essential to know the indices of the

individual fleas and animals if plaue ePrzootics are to

be predicted. Graphical data is useful in planning yearly

control operations but does not have the definitive d at

needed for plague studies.

To adequately follow a flea population and their hosts

one needs to know the flea index of each flea species

during a study. This information is given in Apierdix ITI

Tables 1 through 9. This data provides a fast, efficient

method of determining flea indices that are useful in

pl_ ue studies.

.'..-n plague epizootics occur in wild animal npopla-tii

they are usually r,:.rpetuated by one, or e-1.v a ";., of t

total animal species in an area; and one or rore flo -a

assocl.ated with the animal hosts (Stark and Files 103)

(Lechleit:ncr et al. 1962) ( -H'don et al 171).

The data in the Tables reveals only orne -

plaue problem. In Appendix II, '~ble 8, n.c

(CitjoIln). .)S l_2:z.ha had flea indi es of 3-0 (. c






















\O



-1
Ii







S2















c C
CO
c0
c.














E
C 0
r2



c-








Ctt r-

*r -






CO





o;


L O pq
*>*
/i~u ^a s'0 'can























o
O






cC
-p



10


C 0



C..









*H
*
,- 0



















Co


bN
C





C --


/ bC








T^UTU. S+6
.^ ^''^ *a cc!~ b~~n
,^ -^'^ ^ >!-




























\O

i 0





0

















C '0
--- o,.
.- 0























FC-.
CJO




'C .




















0 0
C H

























"--0
WUB JO s~J oJeAV
C 0















C
C'
o H




o
0

o E
O C)





CO
O t

O 02




O
























C
\ ?-4















C C)
\ 1




C










p C-(












-p1





































.r- -
LO
ri















r-


:0
/ -P




















r- ,


























ooQ
C C
































n.;

























,c
0
cm C

r-v




C C"
.0















-,-J










C












C\C
FOt
-.- O



: r-.'





























rbJ

-- C
fcl-























AC

















0
s
r I














CO
< 0


c- c



i- : >
d0






C3 Ci
AiC
r; **-i






Jt;


STZ
r."




r-l
C
r"CC


C .1


`C -J s JIO Sac 3-r


C'
h" r:



















O




o .c





o
*ON

.0


a 0

CC)



H 0,
0
S* OO
/ 0 ,

< 0 O0








co







p CO





S00C











0 >O
-^- 0




\ O v, -O








C\2 C1 C
uB^an t "I

e ro
^'^ -O^ .'CU)O
























r" " i? I ':

7n psxi--


1

- 7 v ;Ca -f o


f-
4'


e l atory stu'- of flea control tec'--' 'ues ?:as

conr 'ct d at the U S D A IAn>osects Affect" r. -!.an and



is Portion of the research; was an 3 ot to ev.al te. .


70-c now pentiol, plagre control 7=7-7es-

"?-trha o "d7 h-ve been usend in 1oa control 7rc s

"rolvin ,- 777e enizootics in the western U.S. As pre-

-. n oned n t -o vio: section the problem of

cc-A-M711 wild nirl flesr ic rri-oril one of arp l lc

tion -W..hod -ther th-n effective insecticide, tprets

inr^ ti& 7r-r*. ntr -esr-e- t e -tes tRi;e t "a new cr0 nc-t for O
b< oazo CO^ ,CC 0

c'-"=l0. P cnc mpnp con 1?o-" g7 i7onvoLvc spr'S '1 = /




--& 71nom 7053) (Vollitz-c; o0), ?n h-V 4- -' *


C- y O


i r 0" r. n '-- r -' O




cot e bt b "vin7 e data availa3 / i 1c

.... ..... bov --- .... _
sc y 1 e-o f, can be qrickC'

r ten z- alert the ?ren to R rossib



th ta isc d a e ACpenix I


,.give host-flea .reference information

abundance of various flea s ec'ies c











la-ons an bli t-coate ..ch.l.r..s are bein- c- ta

at the U.S.DoA. Laboratory in Gainesville.

Prior to initiation of tests the followin- assumption

concerning the feasibility of the study %were rm :

1. No completely effective method is available for

controlling fleas under field conditions.

2. Wild animals are repelled by many materials,

making the use of insecticide in bait form limit-

by its attractiveness to the animal.

3. If an animal could obtain the toxic material

internally, without having to feed on a treated

bait it would be less repelled by the material.

4. Wild animals dislike any forei-o matter on

their feet or fur.

5. If a foreign substance is on the anil it .,illK

nor a.lly lick it off imrediotely'

6. If a rat could be lu.ed throw: o r- c- .-. '1

thnt would adhere to the rat's feet or lur it : '

lick it off, thereby t.lh- .. the sLstance into rl .

Initial tests were run to eva..lua th v lid of

s~ s ,t i.o. Fenthion, found effective as a S .." o

lea control on wild ani-als b:y C':, eot al (

the inrcc-.Cid e o. coic. mt ,

and vaaoi. no, were cho:en r. Poe' i "l C1 ," ..'. .

















i'enthson at snd ..3 percent ri>xt>resR in vaselirne.

ed ... tc o f t0he f*eo]pt oy'n '^p sc ,



-co-t'ro 51i Oo"t t the SGeek of test-p -.n

se l er 5 result-7 ..ere enco our Cinr so6 tess si't--, a-

.. field conditions v.-ere -.st3d ext e artificial

r7at r;n-s 1o e se d and hoodCd rats .ere forced to pass

: -, d forth th~ro, -h. 'the run, less oroisi~ result v were

ot edo To reduce the flea index 50 percent, the rat had

to cross the 5 percent vaseline-fenthion mixture at least 3

ties and 5 times for 100 percent control, It is felt that

a method such as "'-s is not practical unless the rat can

ick upn enough material on one run to kill the fleas pre-

rent. Vasoline, althou-, it didn't seem to have a repel-

lent effect on the rats, was avoided after the rat :ot it

o it feet e first time.

'" t te st 'vere a f-ial attemt to see if an

aceico control could be expected from this approach.

nhe results of the tests done in 2.- "--;. colony cates

;ere n-ot0 Sicesr'l I- 5 the treated areO h7,d as

n- or in so3" so a ses more fleas tha- did the control

cr- It i t s method of control for f on


r'f ~ ", 7,' C .?"


--e c













Laboratory:, for flec control '" systemic and v' or ect o

seer to have potential qualities to control fleas und

field situations. These materials, like tis o teted

would. be li.-nied to sm-ll area control nro:ramsn '

would not be practical for large scale operations to con-

trol fleas associated with epizootics that cover thousands

of acres.

In the future, agencies responsible for flea control

operations may have to rely on their knowledge of the

ecological associations of plague as much as the use of

insecticides in any form, If basic host-flea data such

as presented in the field portion of this stu-~ eree

kcnovwn in arens where nlague eri7cotics occur, a ri

survey done yearly, could potentially predict oncreing

e .iccotice Once these data were 1'cnown control

such as previously discussed could be bro:,-ht into these

areas having small foci of plague and effectively co-t-ol

then be'ore the eDizootic sCre'ds i conce

recuiro lon.-rnw e ecological studies 'ron v'iy o

lora. '~d f.uno, Psociti ons lue ir et r



could -ossibly produce djat t-a cO ii

rro^3- nreviOulr- infpcted !.-TI..






















to .M i V R Ko c h .-






,t v 7 ,< C t h w .... .. ... .c...
""C "1 -, '









Sr- -Icsi""- 0 elation c as se

=1 t -*rn' to occ^r''renc" e of l'--ue p*cizootics-



-- indices indices of dvid' f1e

'0-07 AdVTa.n,?.:es and disadvantges of bcoth o- c'-" 7

. re-o '?r"en ta 1 ion '"QTrPe Vrfven

V^ ..l .ia of' I potential thod of con't lin:l

7z. onra nP fetho---Mn mxu in rat
-, Q "in s t c-di e 'n c *e Co" t' w7 ot -r




";r'o" '" h o" cop.t ol0i 01 0r C or -C^Cr"--. n-. .-

C7V7- 't 0zV'' a".''" ^ '. t9l q -'i -QQ cc Qn -Po



































APPETNDIX I













0












c m-


C~Ov


ozC3

Cm-


cm-


-D o


cm-


C>


C'>


c'-v 4--


CO-
c--























c-!
s^C r
r'-n -


*c



COCO












STo
\o ,
h'--





c.,..-.,


C C'












CC-


cm-













Ccm-


Cr-
















0 ----'
. .>




o CH







4-'-
O v
.?


ON~--

Ocm-


C \.
r-.


C'


r-i .,~
II)
c

'-

-
--
---~






















0 --



C'-


.0 -
CO r-. CO--
-O- CC)


0 \O






0"Y--

O-






c-
\0---
om


c0-




SrI


C




cil

I1g -


:rD


r .
P.

r


m





,-
C)

S






0

i4

















r-






C
-P



















Q -i


ra


0








rCL
H
-o


ri
1



X
n
---



































AP '"TDX TI













I iI





c rH 0 0 0 0 0 0 0 '0.
,C C c Cc


0 0

0 C r0000 r 0
,dC



SO C O\ 0 0
, -H OCO d








C
Sc; !
0i H 0 0 0 0
O=- H 0 0 0 0 0 O 0







* r- c









*H 0
0 OH 0 0 C







m I .
0- '0 03
OO k





0 o- O r-
-P H O O 0 0 C


1. ^0 ;! C
4i j 0






,o H c
C ,C C'-' C


ra K- &- i~1 B'




,o a O '-I



9 i c i :

























0 0 0 0 0

0 0 C ,o 0 0






0 0 0 0 0 0
0 0 0 00







0 0 0 0








CO 0 0 0 0
e e e

o 0 0 0 0 ,0







C r-' C 0 0
* e a 0 e







c

o fC

f l :


r-' CI


'C


-l'

*' U-I
..I Ci
rr*e





e e.r r


0



(..


0 S"





C 0
r

c-; d
_f r"
.{r_
i.





0", \
0








Sbr



-5 0c





















o i


















C1
I












r-





c I





*r-



C










c- 0 0

CC





r.
P _


_ 0
.0 <
C


r-l 0 0 0 0 0







I, t 0 0 0 *







0 0 0 0
C 0









CC C 0 0 0 0





O- 0 0 0 0 0


o c
t r0


r


.^
c--


"ZL -i r
*, L-




*11


O H;

H
0

c; (C


t.tf


























,o 10 10 ,P


0 0 0 0 0 0


\ CQ 0 0 0 0C

SI0 0 0 0 0 0


0 0 0 0 0 0
o o 00 0 H








C 0 0 0 0 C
0 N 0i 0 0 0
0 0 c't H H 0


C-7
.,


cc"i


(ct


0L-


O 5:
i- 1--i
rr,
ci;
i" a

r
t' p"
C? I`





















O 0
o o
O 0





o o
* *
0 0


,C-
Ci-


O











:5








0 d



-Ho
C) C




C
ON






0

si2 ::
or H

4 -







C).
*Ho I



-'
CO::










-4-0


o 0
o 0o


O 0

o o
0 0



















C I


- *
b! T;|


O

o o


CO
H
rC
d
E
*r
C



0







'-

C


O



C .
O H



0



z
i O

H E
-e








CO


'" c





So
C) -1









































i-q C C

cx lc0C


xC o oc

C C 0 C


0 0 C 0 0














0",C0' C


ri,

T"r"
6j ~

C "r
r: C
~- cr
c



c:
rl S~
.r;



e

\"

C
- J~
--




r"
j2
;;

r =

r;
h
S-"


-i- ~d
I^ "
"J rfi
d c
c:
C
c c?
,r:
c:
ci
- ^
-

'P
ii


Li





















o c\2 ,'f o o o o o
C C\2 0 0 0 ,C O

,.-4




r- co c o o

S 0 .O OO O


C)

O j
co


-o



C-
c

0



c on

























*H i
' '

















c -
o ^'.I


3)
>:
h


C)?
H;


r\i









o


o


N ,C





C
-p











I C
'- C









O r


o o
-p &'C
00 P.


H O r 0 0 0 0 0 0











rci




-i 0 o .-O- o o c,' o 0 0

S| 0 0 0 0 0 0

S, '

iI --







-. i
1' .._
*'l r xl '



21 t '[


- - C
Ir ; .
r. _,, c | I


"1 "
Z
'"
F~i t
c


l i I


/
























S 0 0

0 0 0 rV


: I 0 0 0 0 0









oi c~ c


'





C -~







o"'c






C cO



CO
c -
SC\












Sc

"O
S-

C$
-r v







C0;



CM
C

'oh


CL



^\3
>ri





or


C


c C


0 0

fC 0 0 i-




















cH


HR
C



C




CJ

C



0
C-










C)



-H
Hn

0l



C,


o
O E


O Cd
o


0o




o



'2




CO O


Ic c I




















I J







c0
a










.,.

















0 q
) H
C 0
o r



















P-4 c
..o a


ot















co
0 0
1 : C
































cj ri


0\ 0 0 0







(^ \0 0V 0
* 0 *



0 0 0 0














0 0 0 0



o c


o 0 0 0
* 0
p-^ 0 0 0










CC






*I i




c


e-







o



0




rc
0
















rc





Cr







(L)
+-

















-ins, o M ., J.L. Sc -l





f" "" CIe ri o' c



Atiar of Olaue- 1952. A


I .. r. Lum . n.L Als't Sci". ..
'. l ce. S

Izay +_o


... ? .. 1 or-f th pe Sf icsr0- 1 of th"e COm -C.


h s a encto t
o o" p - o t.-2 in e t A 27 1. e rtsg :



-Q -^ 7 Q--^ ,0K 2%n p p- '^ F-i- -- -^I pc"'
IT-: M?7-'5'

in ""- L artman% : M,, ofCo --n ? o a __,
'-, fors orn di'Tna.3 ro e ...... +l he S'.alrrx. V Mevad ". ...
SC .if-ori? -" use of insectici-de bai .-boxes *-
-- I

.--n iE, 1 0% i ec;ici'f nd .-..t for
S.. 7 on 53:1 .7n


, ^ "c."t .^. ,-^ JL 0


7.o --(- of "eCne=! of r-t I--
- o : o\ ro:on y 4r ......, itoC
Mr1 0;) ,wdent 7-ir f ',"2'%" 1
-' i *--'-, ~ - ^] ^ 7 -yi | -n j" .: I *- ^^ **" s -
Sy rr ^*^ -- 1f.*.T-** p ^ 1 y ^f f. ^ ^^"-''^* T ^c


. 10 M


SY-7_7 I


1V. s-9 Sitles S1 -


9


J* :..r.. l. for h ,i-_ 7?







-:Y. ... ).-. 30 :1r 1w pn ..'.


n thn
As ch .e r:. t er e d A Inlr^,- Institute o-"
Vietnin, "-i. Pro,, ;. Far :. IV. -

Clark, P.H. and . Cole. 1i<9. Systenic i cnsecticiqs
for control of oriental rat flees: ?ait te.ts ...':r.
hooded white rats, J. son, Etono1- 61:5 0-Co-

Clark; P.H., K.*. Cole, D.L. Forcum, J.R. eelr, V ',
Weeks, and B3.. miller. 1971. Prelirinary evalu tion
of three systemic insecticides in baits for control
of fleas of wild rats and rabbits. J, Scon, Enior"ol.
64:1190-93.

Cole, L.C. and J.A. Koepke. IC!7. Problems in interrcto -
tion of the data of rodent-ectoparasite sure a.
studies of rodent ectonarasites in Honolu li T.H1.
Savannah, Ga. and Dothan Ala. Pub. Health -op
Suppl. No, 202:1-71.

Cole, ".I'., D.L. Ve'ar:atta, W. Ellerbe, and F. -- -hin ton,
1972. Rearing the oriental rat flea. J. Econ,
Entomol. Scientific Note. In press.

De.Meillen, 3. 1946. Effect on some blood-suckin rt' nc
of "Gammexane" when fed to a rabbit. nature L: 3o

Drunmond, R.0. 1958. Laboratory screening tests of s '
insecticides. J. Econ. Entomol. 5]1:425-27.

Eddy, C.W., W.S, YcGregor, D.E. Hopkins and iss
195. Effects of some insects of blood a mnnre
of cattle fed certain chlorinated hydrocerbcn incct-
icides. J. Econ. Pntomol. 47:35-58-

Eskey, C.R. and V.H. Ha.s. I'.n. Pl ,ue in the 'e.
oart of the United States. --. 'ed.
22:257-75.

ras. G.E 065. Tnoerature and -iidi' in th" .i.."jo-

n or 1'ito~ l 2:3 13-1

H il. .< R nd Kn R. K.elson .4. *e i'nY1, or ''"-:-
A-nrian. Ron"o1d Frresm, ''. -









C -p '


-0 f


Sri -nd : Foth'ch:ijsd l253- 1
treaty! catalo-9 7 the R;oth-sc

-Svilldae to ATM17o72 ..,
"I I K .eo cm: risce 7niv, o. ss
* 2- 1 ) ^ 1 <- **-^ ? *


C-
6 196, 2. A


* TO, 2.


TVol


**.- .JF .r0 ^' .. .y:,, 20 :2.

n95. 7'y7o 2"- <
a na 0: 2.,







0'0 _r c
""- "- rr r ?"- *>/^w r-1 Q Q'( ft" *r^*' ` ~
^~~~ ~ ii ,- ,y,^y ^^^ Q^^


MD Poln. 9

,T Ti n '*











5-t3V
u '>' T vo"


1- CM0 iT-ric.ric! nd ccol o-^' F ob r,


- 47, O -i-


7 O o* 5 Y 1 th C r -"
730~"~r n~, :COW-


10 l~;, ~ Y-


C r 3itSc]g.o 2? :''-
7~C FC F


2 --7.


vre- f i rfe-e


-'" r


- iz P


1-


7W,"' of C A w c7 sxl.0?vs'tc'^n' Tort
TO"a 5337,"


- nl Z t V


an
ln







Kennerly, Tr.E 1964 icron-r'ironcnt conditions of the
rocket goher~er burro'. x.s J Science -1.

Knling, F,, iR.C. E.sd, -- er. C
and .S. '- va tion o' selected c:
cides and dru s es chemother-peutic a.onts o. i..... .... : : :
external 'biodsc:i -rasites *. J ~ raSi07o
34: 55-70,

Krishrna- -"'-, .S., S. 'a and G.C. Joi. 1"3
Note on techniqiae used in rearin- r nsrina n
a colc e of thie oriental "-t-fla, (.---.. -'-
''Torld Health 0-r-an.o -rVrkin~ *re er

Lechleitner, R.R., JoV. Tilestcn, and L" X'-'artr.n 1,62c
Die-off of a Gunnison's Prairie Do) Coir- in
Colorado, Zooneses Rsch. 1:185-1I,

Linkfield, R.L, 11"6, Biological observations on the cni.-"
rat flea, Xclogs.n a conis (Rothschild), vith spc
studies on the e'focts of the chemosterilant -t'iZ- t-
Aziridiny) hosin) rhshe oxide. ? -D. Dissertationn
Univ, of Florida- 100p

Llindouist, AVr1., E.F. "-.i.plinog, H.Ac Jones, an' A.. I-cden.
1944, Icrtality of bed I'. ,s on rabbits -' ver oral
doses of DDT and pnrethrurm. T,. cone Entoacl
56:128.

1IMacchiavello, A. 1950, Practical absolute rat-fle index
used in nlague control. -"rld Health Orrcn. ch.
Rpto Ser, No. 11:24-77.

MLatheson, R. 1950. medical :T-voolo-r. Constoc: Pb. Co
Ithaca, T .Y. 6l2p.

IlcCoy, CG.. 1910. Bubonic nlaT'e in G'round --irrels
N.Y. 'd.. J, 92:652-55.

Kletcalf, C.L., W-P. 7it, and R.L. i etcal. 1962.
ODstructive and Usoful Insects. tC ,-Ll io
Co. Inc. *IY.v 10 .--

1 zyor, K.F. I'-2. The kno:. anrd "-o nknovr i nj7_1Le
Amer. J. ed. :-36.

i.-il c "L ,and 1 (.J. ...15 ilco cb. -r 1953 Contro o" ti v
rodent flea7s with a]oDlied to stim'+ la-te -o ~l
dustin *T. T'c on. Ento ol 46;:255-57




University of Florida Home Page
© 2004 - 2010 University of Florida George A. Smathers Libraries.
All rights reserved.

Acceptable Use, Copyright, and Disclaimer Statement
Last updated October 10, 2010 - - mvs