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1978

A Study of Symbiosis Involving the Fish-Eating Bat(Myotis vivesi), the Least Petrel (Halocypteramicrosoma), the Black Petrel (Oceanodromamelania), and the Lizard (Cnemidophorus tigris)Joel KingEastern Illinois UniversityThis research is a product of the graduate program in Zoology at Eastern Illinois University. Find out moreabout the program.

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Recommended CitationKing, Joel, "A Study of Symbiosis Involving the Fish-Eating Bat (Myotis vivesi), the Least Petrel (Halocyptera microsoma), the BlackPetrel (Oceanodroma melania), and the Lizard (Cnemidophorus tigris)" (1978). Masters Theses. 3257.https://thekeep.eiu.edu/theses/3257

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A Study of �ymbiosis Involving the Fish-Eating Bat. �

(Myotis vivesi), the Least Petrel (Halocyptera microsoma),

the Black Petrel (Oceanodroma melania), and the (TITLE)

Lizard (Cnemidophorus tigris).

BY

Joel King

THESIS

SUBMITIED IN PARTIAL FULFILLMENT OF THE REQUIREMENTS

FOR THE DEGREE OF

Master of Science

IN THE GRADUATE SCHOOL, EASTERN ILLINOIS UNIVERSITY

CHARLESTON, ILLINOIS

1978 YEAR

I HEREBY RECOMMEND THIS THESIS BE ACCEPTED AS. FULFILLING -.,

THIS PART OF THE GRADUATE DEGREE CITED ABOVE

ADVISFll

tlt,<4' z I lf?f (/ DATE/ DEPARTMENT HEAD

.......

j

·---- -··--- -- . J --������----....�� ......

A STUDY OF S:.J'·'BIOSIS INVOLVING THE

FISH-EATIUG BAT _(r·�O'?IS VIVESI ), THE LEAST PETREL

(:IALOCYPTERA NIC�OSOMA), THE BLACK PETREL

( OCEA: IODROEA Nt:.LAlJIA), MJD THE LIZARD

( C:tIBHIDOPHORUS TIGRIS)

BY

,1o:s1 KING

B. S. in Ed., Eastern Illinois University, 1973

ADSTR.AC T OF A THSSIS

Submitted in partial fulfillment of the requirements for the degree of Master of Science in-Zoology at the Graduate School

of Ec:is'ter� Illinois Urtiversity

CHARL1S '1.'0H, llLPJOIS

�

ABSTHACT

A field study was conducted on Partida Island in

the Gulf of Mexico on the dates May 26 through July 26, 1977,

inclusive.

Field observations were made of the lizard

(Cnemidophorus tigris) preying on eggs and hatchlings of the

least petrel (Halocyptena microsoma), and the black petrel

(Oceanodroma melania). The petrels roost among rock slides

with the fish-eating bat (Myotis vivesi).

In 24 trials of experimental boxes with lizards,

bats, and petrels as subjects, 16 trials resulted in aggression

of bats to lizards.

A symbiosis is postulated between bats and petrels.

TABLE OF CON'l'.CNT::>

Page

Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1

Materials and lViethods . . . • . . . . . . . . . . . . . . . . . . . . . . J

Results . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8

Discussion • • . . . • . . . . • • • . . . . . . . . . . . . . .. . . . . . . 11

Literature Cited • • • • • • • • . • • • . • . . • • • • . • • . • • • • • . 21

LI�'l' OF' 'l1ABLE�

Table I. Results of O. melania, H. micro­soma , C. tigris, and l'i. -vi vesi behavior in three experimental apparatus es • • • • • • • • • • • • • • • • • • • • • • . • • • 1 J

Table II • . Observation date and notes of Cnemidophorus tigris preying on least petrel and black petrel embryos and eggs . . . . . . • . . . • . . . . . . . . . . 15

'l'able III. Hesul ts of Least and Black Petrel broken eggs found and collected and C. tigris sightings in 10 meter by 20 meter rectangular transect area at various times during June and July . • • . . . . . • . • . . • • • • 17

Table IV. �uadrant study of talus 1 on Partida Island . . . . . . . . . . . . . . . . . . . . . . . 18

LIS'i"' OF l''IGUH�:::i

Figure 1. �xperirnental apparatus . • • • • . • • • . . . • . 19

.Figure 2. Map of taluses to show relative locations . . . . . . . . . . . . . . . • . . 20

ACKNOWLEDGEMENTS

I am indebted to Dr. Jaime Maya for his help and

direction in this study. Without his great personal sacri­

fice of time and money I would have been unable to have

undertaken this project.

I am also indebted to Dr. Michael Goodrich, Dr.

Fredrick Schram, Dr. Bill Ridgeway, and Patrick Malone.

I would also like to thank my wife, Cindy, for her support

and assistance.

Quiero tambien expresar mi agradecimiento a los

hombres del Poseidon de San Felipe por su amistad.

IN'l1HODUC'l'lON

Partida Island is located in the Gulf of C2�lifo!'nia

at 28°551 N. Lat., 1 1 3°

01+• vJ. Long. 'rhe island consists of

a microhabitat where relationships between organisms have

evolved.

The fish-eating bat (Mvotis vivesi), least petrel

(Halocyptena microsoma), and black petrel ( Oceanodroma

melania) roost together under large rock slides or taluses

on the Island (foaya, 1968) and (Burt, 1932). The ve5etation

consists mainly of cholla ( Opuntia ·platyopuntia cf. bravoana)

and card on cactus ( Pachycereus Qringlei) • 1./.iyotis vi v ... �si is

the only permanent land mammal on the island (Maya, 1968).

Burt (19J2) reported that the bat and petrels live

togeth8r beneath stones on Partida Island. Quoting from

Donald H. Dickey's field notes, Burt (1932) stated the

ratio of birds and bats: bats, 10; least petrels, 10; black

petrels, 1 on Partida Island. Maya (1968) reported the

population ratio of bats and petrels on Partida Island as

follows: bats, 3; leas t petrels, 3; black petrels, 1 . He

stated that roost selection is non-random.

WcLellan ( 1 927) stated that the bat was found

occupying roosts with breeding black petrels.. il'Jalker ( 19 50), referring to taluses on Partida Island, reported a "s�range ; associat:i.on--ne�-:;tlinG birds and suckling bats within inches".

1

Diguet supposed that the bat fed on excrement from

the least petrel ( Miller and Allen, 1928), but gave no evi­

dence of this fact. According to Maya ( 1968) and the field

notes of my co-worker, Pat 11.Jalone, the lizard (�:nemidonhorus

tigris ) preys upon the young and eggs of the petrels against

w hose attacks the petrels are relatively defenseless. �aya

(1968) postulated the presence of the bat as a deterrent to

Cnemidophorous tigris from entering the roost to prey on

the petrels' eggs and young.

Symbiotic relationships do exist among other vert­

ebrates. Barabash-Nikiforov (1959) reported on symbiosis

in beavo:c burrows with shrews, toads, grass snakes t and

muskrats. Neuntefol ( 195J) reported on forest birds' sym­

biosis involving feeding and group VJarnings. V�ymand and

�;Jard ( 19'12) and L:cCutcheon and f11cCutcheon ( 196L�) report on

cleani:n . ..:� 3ymbio::iis in fish. t'�O information c1:rnld be founri in the literature.to document such a relationship between

bats and birds.

The present study investigated Maya's suggestion

of a cornmensal relationship between the petrels and the bat.

2

l'.iAT.8HIALS AND Nlli'l'HODS

The field observations for this study were made

on Partida Island in the Gulf of Mexico at 28°55• N. Lat.,

113°04• W. Long. The dates of the observations were hlay 26

through July 26, 1977, inclusive. �ome observations, as

indicated, were contributed by co-worker, Pat Malone.

Bats used in controlled experimentation were

obtained initially by mist netting at the entrance to a

night roost . These bats were kept in flour sacks until

daylight when they were utilized. Bats kept overnight for

the experiments were usetl only in the May 27 results in

Table I.

The vast majority of bats used were dug from

taluses in th0 early moi�ning, Ht.ilizcd, and then set free.

The author felt the bats in the flour sacks were subjected

to much stress, due to their fighting in the bags overnight,

and results could be affected. The petrels used in the

study were all obtained from beneath the taluses the morning

of the experiment.

'.i.'he rnajori ty of lizards, Cnemidouhorous tigris,

used in the study ·were captured in pit traps that were checked

every mo�ning. These consisted of gallon plastic containers

buried with the opening even with ground level. 'l'hey were

buried a:c-ound lizard bu!.�rows and r:ioved every few clays. J\

few li z ards were capturod by hand in a garbage p:i. ·�. Captured

3

lizards were held in flour sacks until their introduction

and observation in the apparatuses. 'l'hey were released

after each trial other than the one used on .. 1ay 27 in

Table I� tihenevcr possible, all other animals utilized

in the study were released unharmed to the taluses.

All observations and experimentation were done

during daylight hours, the majority between 0700 and 1130.

rl'hree enclosures were utilized in the experiment­

ation in which various combinations of bats, lizards, and

petrels were introduced. (See Figure I for dimensions of

apparatuses and Table I for combinations of organisms). Apparatus I consisted of two enclosures. Enclosure

Ia was a narrow crevice with Vlooden base and sides. The top

was screened and there was a screened opening at the base

secu:i;-ed by thurnbtacl;:s.

;�nclosl,i.re Ib was mu.de· up of the rem3..i.r1der of the

wooden box. The top was screened as was most of one side.

A1)paratus II' vms a roll of screen. A safety pin

secured the front screen flap.

Apparatus III was made of cardboard and screen.

'l'he opening flap was cardboard and secure.d by masking tape.

The.top was screen as was the end of the rectangular corridor.

All trials with apparatuses were conducted on

talus 1 near the bottom of the s lide (see Figure II). The

apparatunes were set on top of the rocks ancl results were

observed. Rocks and U.irt were placed at the l.Joi;tom of all

apparatuses to simult�te natural conditions. Apparatus lb

4

was the largest and thu�> had the largest rocks in it. High

temperatures in apparatuses and bright light were problems.

but by testins montly in early morning, placing apparatuses

on top of the rocks, and by shading with cloth over scr�ened

areas the problems were alleviated.

Bats were given twenty to thirty minutes to adjust

after introduction to apparatuses. This time span of

adjustment was selected after observing the duration of

squeaklng and scurrying around behavior, exhibited af'ter

introduction into the apparatus during initial observations.

When petrels were uBed, they were introduced first ru1d

immediately followed ·oy the bats. All apparatuses were

darkened by cloth before introduction of any organism.

Specific procGdures for apparatuses are as follows:

Ai;paratus Ia. Bats were introduced throuc;h the side

door. 'rhere was enou[;h Jight to observe trccou:;h ·the ;,op

screen. Lizards were introduced after the bat adjustment

period and all encountcr·s were noted through the top .:-;creen.

Apparatus lb .. Bats, petrels, and lizards were intro-

duced through the top. �nough light was present to ob3erve

throuc;J t the top and side screens of the wooden box.

AJJparatus II. Bats and lizards were introduced :into

the wi�.cc screen through �.;ere en flap opening. The fla.) vms '·

secured by a safety pin �fter introduction of the lizard.

Observ�·tion was possible through uncovered screen are�s.

;.. 'i�.;aratus III. A �ii.ngle bat \·1as -introduced int�.-'

5

cardboard tuba through cardboard flap and observed through

top and end screen. 'l1he flap was secured by masking tape.

Petrels and bats v1ere acquired by rapidly li:fting

rocks from the sline and \·1orking outwards in an approximate

two foot square area to dirt base.

Eleven quadrants one meter square on talus 1 vvere

analyzed by lifting rocks from the middle rapidly and working

to dirt botto111 and out to the periphery. The meter was

measured out with a meter stick .before rocks were moved.

Quadrant sites were randomly selected. :Numbers of petrels

and bats were noted.

A single transect was established on a study site

utilized only for this purpose. It was analyzed twelve

times between June 4 and July 14. The site was located on

talus 5 on the north side of the island (see Figure II).

1l1r1e site i:.:o.s on an 3.ppro:;dm.::ite !�.5°

embrmkment wl th the oase

line of the transect at the foot of the embankment. Talus

5 consisted o:f larger roclcs and more exposed ground than

other taluses observed.

The transect was 10 meters at the base and ton .. ,

with 20 rnoter sides up the embankment. It was then divided

into five 2 by 20 meter strips for easier analysis. Orange

cloth was used as markers for the 5 strips.

'l'ho transect was analyzed by v;alking slowly up ai1d

dovm the 5 strips one time. Sightings were noted of

Cn0mido1)horus tigris and petrel ege; . fra.�:ments, and tho

6

fragments were collected.

li'ield glasses were utilized in ma.""ly of the talus

observations . .

7

Rl!;SU:L'l'S

'l'hirty-one instances were reco::--ded by the author

and co-worker, Pat Malone, of the lizard preylne on least

and petrel eggs and ha.tchlings (see Table II) . The first

direct evidence of li�ard predation on petrel eggs wa�

observed on I-.iay 31, 1977, when a lizard shot ,.,i th a sling-

shot vomi tted yol1<::. A lizard was last· observed feedint..� on

a least egg July 18, 1977. The last record of petrel

predation •:Jas 1:iade J'uly 20, ·when a lizard was seen eatlng a

least hatchling.

Most predation on eggs v;as observed betv1een i.lay

31 and July 2. Between July 2 and July 20 most predation

was on hatchlings.

served between June L} and July 1L� (see 1rable III). On

the first day of the transect , J·une 14-, nine least eggs and

one black egg were found broken. On the last day the transect

was run, July 1�, two least broken eggs were found. �pot

checks of the transec� after this date revealed no more

egg fragments. 'l'otal eggs found in the t:cansect ware 52

least <Jnd 7 black.

As previou�:ly stated, Burt (.1932) recorded the

ratio of bats to leasL petrels to black petrels as 10:10:1.

rf!aya (1968) had stat;.ri J:J:l. �l-,\"en quadrants run i.\.'.' the

8

author showed a ratio of 2. 5: 1. 5: 1. A total of 1�5 sightings

recorded o:f petrels and bats, v1hile digging in the taluses

:for experimental subjects or just observing under the rocks,

resulted in a total of 50 bats, 49 lea3t petrel�, and 12 black

petrels.

Results from the experimental apparat uses a.re

given in Table I. Four different types of responses were

noted for the bat when encountering the lizar d in the

apparatuses. 11'hese were shalcing, squeaking, bi ting, and no

apparent reaction . Apparatus Ib was the most successful in

showing bat aGgression to the l izards . In six trials

between bats and lizards, aggrcr.>sion was shovm each time

by the bats with the lizards rapidly retreating. Apparatus

Ia had ten trials with five resulting in aggression.

Apparatus II was run for three trials with one case of

a,,. --rncs·� ') : 1 bS vO -� ' -- • throe out ol four

with agcress.ion. 'l1he aut:nor felt Ib was the most success-

ful bec ause it was the largest enclosure and the bats were

more secuce beneath the larger rocks.

One incidence of a bat biting a lizard was seen

in the :f'ield by Pat i�.1alone. �1hile pursuing a lizard over

the talus, the lizard went in aJ1d out of the rocks. �L1he

lizard at one point was seen to be struggling in place on

a rock with a squaking bat firmly attached to its tail by

. Daily observations ware made of lizards enterlnc

9

the talu::;, folloV1ed by loud bat squeakin�;, and immediate

reappearance of the lizards on top of the rocks. rdaya (1968)

reporte:HJ. the bat squeaked when moving in the talus and

encount0.d_ng other bats. Due to the 1a:-r;e numbers of'

observations where lizards entered quiet areas and incited

rapid squeaking of bats, the author feels it is valid to

assume aegression of the bat to the liza�d.

1i'he reaction of petrels t when disturbed in taluses

by the author, consistod of a high pitched cry, light pecking,

and rec;urgitation of fish oil. Maya (1968) noted the same

reaction for petrels when approaced by c. tigris. The only

instance of testing an adult black petrel in apparatus Ib

resulted in the black petrel flapping and attemptint; to

flee the enclosure when confronted by the lizard as it

crawled through the enclosure. In trials witl1 l east petrels

cluckinz noises.

1rhe low number of trials with organisms was due

to the resulting destruction of habitat ·:.ihen escavating the

taluses. Also, all ort.;ax1isms studied were involved with

breedin_; and h2ndling could be very des LL·ucti ve to the

species.

h1aya ( 1968) reported the bats �";ave birth from

mid-f.,'iay through mid-June. f.iany bats wei.··� found with young

during this time. Palmer (1962) reportoJ the petrels'

hat;chir. ;.:; occurred the last d3.ys of �.1ay ':hrough the first

three w��ks of June. �he author found t;is to be t£ue also.

10

DISCU.-:>.SIO.N

Layo. ( 1968) rcporteci. that Cnorni<lo·ohoru� ti gr is

preyed on petrel eggs. he also observed a.n instance of

a least petrel hatchlinc; taken by a lizard. J\s previously

stated r.Iaya ( 1968) reported roost selection by petrels near

bats to be nonrandom. He postulated a commensal relation-

ship with the bat being a deterrent to the li�ard's entry

to the talus and subsequent predation on the petrels.

/\ccordln6 to Bert ( 1922) the least petrel egg averages 23. I�

by 19. !� r.nn; thG black petrel, 36. 6 by 26. ?mm. Gnemidophorus

tigris is capable of easily seizing the egg. Cnemidophorus

tigris are predators of least and black petrel reproduction

at variouf; levels.

the bats' aggression was shovm to be highly e:i'fecti ve. J.,i 7.ards

would freeze at the sound of bats' squeaking or rush

frantically around the enclosure to avoid beinc_·; bitten by

the bat. In trials where no apparent aggress.ii.>n was shovm

by the bat, stress is hypothesized as the reanvn. Hand.lint;

of the bats being the stress producer.

Petrel dis·tress calls o:f disturbance�: were hoard

daily th:.:-ough late fiiay to mid-July. 'l'he petrc-�1 s were inef:fec-

ti ve in driving the lizards from their roosts .i.n the talus

due to their li�)1t pecking.

11

�he petrels' hatchin� period coincides with the

birth of the bats. It is pos3lble that the petrels evolved

a hatchlng period to coincidG v;i th the bat's i;'laterni ty Cal"'G

since the ag5ression of mamrnals is usually at a high level

during this time.

The remains of petrel eggs denoted the young of

the petrels are not of the first clutch and ·that the petrels

lay continuously through the summer months. 'l'his conclu­

sion is reached due to the larCTe number of broken eggs fournl

daily .i.n the same area.

No re111ains of bats \1e:re found in the lizard st0!11ncj1

analysis done by Pat v�alone nor were any bats seen preyed

upon by C. tiBris .

In summary, heavy p.r�dation on petrel eggs and

young oy C. tigri s, together \·1.i. th apparently ef.fecti ve

defe:n�d.ve att;;;.cks of Eyotis y_.i '!..�Si on invadL·-·:-:.: C • .1i:n;ris,

and t;.c absence of remains of !�-yetis vi vcsi in stomach

analy�;.i.s of C. tigris, suggest.s that there in a commensa­

tistic relationship and I1�aya' 0 hypothesis is reasonable.

'rable I. Hesults of O, !Ylelania, H. microsorn:.1, C. tigrin, and Ii:. vi ves,t_ behavior in three experimental a_pparatuscs (refer to f'ig. I for diagrams and dimensions of apparatus). f = female bat; m =-= male bat; yng = youn�;; 1 z -- lizard.

Dtl·;� 'Ti1.�c �l?J2.U-��l tu s ·"·5 27 ,.. - - 0620 Ia

5-27 0700 Ia

5-27 0710 Ia

5-27 1300 Ia

6-3 0930 Ia

6-9 0910 Ia

6-11

6-19 0900 Ia

7-6 0800 In

7-7 0700 Ia

6-28 1500 Ib

7-12 08JO lb

�ub:ioct�

:f lz

f' m lz

2f m lz

2f rn lz

f m lz

m lz

Jm lz

2f m lz

2f

lz

m lz

B petrel lz egg

Behavior

-::-.-i-r shaking and squea!dng

m bites at lz

lz moves over f no reaction

m squeaks and bites at lz

no reaction f n bites; squeaks loudly at lz

no reaction

!lo reaction

no r8action

no reaction

110 reaction

petrel flaps and attempts to c;et away; lz scurries a.round iJOX

2f-1yngf 2f very �ggressive to lz; llcast w/

ynr; 2 lz

13

j>etrel clucking

'l'able I cont.

_D� a _t_e��1-'i��e��-A_P�P�a�r_-�a _t_u_s���S_" u_t_)_j_e_c_t_s �����-B_e_h_a_v_i_o_r��--�-

7-21 0800 Ib

7-22 0800 lb

7-23 0800 Ib

0815 Ib

7-25 0800 Ib

6-3 1030 II

6-11 0655 II

6-19 0900 II

5-28 0630 III

6-J 1000 III

6-11 0650 III

6-19 0900 III

2f J yng, 2f, 1rn yng black 1 lz bats very 2.ggressi ve to lz

2m 1 least 1 lz

2m loud squeaking and biting at lz� petrel clucking

m bats squeaking and very f aggressive to lz 1 least w/

yng 1 lz

2f 2 lz

rn lz

m f lz

2:f 1 lz

3m 2 lz

rn lz

rn lz

li1 lz

Jm 2 lz

2f aggressive to lz loud squeaking

m aggressive biting and squeaking

f bites lz 4 times

no reaction

m bites at lz

m bites and saueaks at lz "-

m squeaking and biting

no reaction

"'�same subjects used for all May 27 trials

·:H:·all trials where bat aggression noted resulted in lizards scurrying away

1fable II. Observation dat G and notes of Cnernidophor·us ti.oT.is preying on least petrel and black petrel el'i'lbryoes and eggs. (1 = least petrel; b == black petrGl)

Da·-'-tc.._· __ 1.Pim . .;:;.e ___ �_c __ ) b"-s"-· 1.::-'"' �_c v_·-=a-'-·c--i _o __ n _____ ________ ____ _

.5--31

6-2

6-3

6-6

6-6

6-7

6-7

6-8

6-8

6-8

6-15

6-15

6-17

6-17

6-22

6-22

6-30

6-30

6-30

7-2

7-2

7-2

7-3

!..015

0900

0730

0800

08!.;,0

0855

0917

08JO

0930

1035

0910

09J7

1055

0854

091.:.5

0855

0910

0917

1218

1 /1.35

l li-45

0050

l� shot 'tv/slingshot and vorni ts yolk

1 egc; set on rock - lz pokes it and runs o:ff

egg put in styrofoam tube on talus - 1030 egg c;one

lz seen with egg shell on leg

fresh broken egg found on talus

lz seen with egg shell on mouth

lz seen \tlth feather tufts on mouth

lz seen dragging b egg out of talus

lz seen retreating from broken b ege

lz seen running with l egg in mouth

lz exits talus with egg

lz s8en c.:ating 1 embryo and yolk

lz vvith embryo in mouth

1 z exits \'vi th egg in rnou th

lz eatins embryo

lz seen ·;;i th eeg

lz seen E:�ating yolk and embryo

lz seen G·caclcing 1 ec;g and eating embryo

lz seen 1·d th large embryo

1 z seen ':.:.1. th lart;e embryo

lz seen .... i th embryo in mou-C.h

15

. '

Table Il cont.

Date 'J.'i.mc

7-3 0925

7-3 0935

7-3 0955

7-11 1000

7-11 1010

7-11 1050

7-11.} 0900

7-14 0950

7-18 07.55

7-20 1000

Obscrva ·t;i on

lz seen with part of embryo in mouth

lz heard dragging egg under rock - exits with l egg

lz exits talus with larBe hatchling

lz seen with feather in mouth

lz vii th live chick in mouth

lz with 1 egg

lz seen by P. Malone with chick

lz seen running with egg, cracking it, eating embryo

lz chewing on old wing bone

lz eating large hatchiing

16

I l l l

I I I I

.1 . '

: I I; , I . ' ,; I

• -1 I

ii.1able 111. Hesults of Least and Black petrel broken e�T'J°"' bb0 found and collected and C. tif�r.is ;:;ightings in 10 meter by 20 meter rectangular transect area at various times during J·une a.nd July .

lJate ':time .LE:ast egg Black e" ::r Ut:> c. ti gr is

6-4 0815 9 1 2

6-5 1015 5 1 2

6-7 15JO 7 0 1

6-8 16JO J 2 0

6-9 1015 8 0 2

6-11 0910 J 1 9

6-12 1200 1 0 1

6-16 1L� JO 1 0 2·

6-22 1100 4 1 4

6-29 10JO 5 1 2

7-8 llJO 4 0 1

7-14 1000 2 0 4

Totals 52 7 .30

1?

'l'anle 1 V'. IJuadrant study of talus 1 on rartida lsland.

Date

5-29

6-1

6-1

6-5

7-10

7-10

7-10

7-10

7-12

7-12

7-21

'i1otals

L = Least fctrel; B = Black �ctrel; � : �ale bat; ¥ = female bat; � = �gg; U = 0ex unknow� due to escape; yng = young.

�U8.dra.nt No.

1

2

J

4

5

6

7

8

9

10

11

·Bats

lU

lU

1Wi

Jl''-JyngU

11•1

1Fyng

1F-1Fyng

2E' 2r"yng, lh:ynr

2.F', 2yngU

2.F' 2F'yng, 1 hiyn �

27B

18

Petrels

4L-1J..� each lB-11�

JL-2h

1 B & nestling 1.L-1.C

JL-U� each

2B nestlings

1 L 2B ncstlings

lL nestling 1B ne8tling

lL nestling lB nestling

lB nestling 11,

1L nu0tling lB nestling

16L-1li3

Apparatus la and lb

lb

' .... ... ·'

' ' ..... ' ........ ,,

' ' , , ' ,

' ' / ,

' _,, •-' 32 cm.

10 Apparatus 2

Apparatus 3

, , -

, , , ,

,, I

__ ,, ,,

< -cm.

' '

32 cm.

'• '• I I I \ ,' I . •

3.5 cm.

' '

, , ,

' '

, , , , /

------- , -

' ' ) 15.5 cm. , ,

2.5 cm.

_ --30�. 5 cm.

_,----;-� -------.,. �-,, -- .....

6 cm • .

---- --- 8 cm.

Figure 1. Exp�rimental apparatus. I'; , .. ,

------. I

l t t I I ! .1

l : "!

. ! r, .. I

I

! I I l I I

�-J.

. .. ... 0

.,..... r :€·v1�t 2.

#'

-.

,,J --7)

0

O• p 0 C>

er � ¢

b <> 0 .. .,

Talus 2f ••.. ,

Cfi1�; if?;lr�1� �, • '1 · f l 1 h1 ' ,./ I I ( ' 1, •

f I � : I ( ).�� t �! I l( ! � ' � ,i ·· ·· · \ � � l . "' ft, l),f

��s� .. 0

... .

c::>

400 r.:eter plain Talus 5

.

/ 1/1 �l_r, - • c;::::::.� ... -1 ________./, (\.""'\../ /,>. / � -

// �· e .

. -:_A, ;o'.

r -�

! ./ - c> •

0 •c,,,. -

C» -

0

/ /

c. .1 "f

<-O" C> ..._ �

. - -•;o":. ' c.- �

T"-p o.r .:..a11u.cer- .t..c s,,_/"\ll' rel..,-'·1·,,e loc-.J..1'o"'S No d 1' .,..., ,. . l" c: 1' or>S �· iv"'"' .C'c-� .t.. ..., ,,,r- , arc·� (....... - V � ::- V ' .._,p' - -Cl.\.. t t:l.v a.J t ;:t..,_;, ._.._.. .1 . ... . . r:- 1 .:. J. J • \JC .- ·J .::. ... _ ,:.:_,

LI 'l'�rtATUJd CI'f .t.D

Bar."lbash-Niki for ov , I . l . 1 9 59 . !:>ymbi otic re lat i. "'ll:sh.ips in b eaver burrows . ( in Hussian , i;ngli s h summary ) . Zool . Zhur. J8 ( 5 ) : 761 -767 .

Bert , A . C . 1922. and peli cans . 1 56 - 1 5 8 .

Life histori es o f North Ameri c an petrels rlull . U . b . Nat . Mus . 1 2 1 : 1 2 ) - 1 25 ;

Bur t , w . H . 19J2 . The fish- eating habits o f Pi zonyx vivesi (i'1iemegau x ) . J . l"11amm . 1 J : J6J-J65 .

Ma:.n11 J . A . 1968. '.i'he natura.1 hi s tory of the :fis h -eating bat , Pizonyx vivesi . Ph . D . Thes i s . University o f Ari zona .

. fucCutcheon, F . H . and A . � - rocGutcheon. 1 964. Symbi o ti c behavior among fishes :fror:i temperate ocean waters .

::> c i ence 1 45 ( J6J5 ) : 948-9•�9 .

i\icl.ellan, 1·,i . � . 1927 . P l z onyx vivesi on I s l a Partida, Gulf o f California . J . I.iamm . 8; 243 .

fiiiller, G . 3. , J r . , an<l G . Ivi . i\llen . 1 928. 'l'he i�rneri can bats of the genera Myo t i s and f�zonyx . Bul l . U . S . Nat . �us . 1 !.;.l� : 20�� - 2 t /.j..

Weuntefol, Adolfo . 1953 , Un e j emplo de si mbi o s is temporal de aves silvestres . Hornero 10 ( 1 ) : ?'J.- 7 7 .

Paliner, rl . :::> . 1 962 . handbook o f Horth 1,.rneri can birds . vol . 1 , Yale University Press . 56 1pp .

�val. -ter, .L . �1J . 1 950 . 'l'he fisn bats o:f Pescadora. Audubon filag . 52: 29L�-299 .

dy:'. ·-.m , H . L . and J . A . �·Jard. 1972 . .A cl eani n[;, syrnbiosis between the cic hl i d fishes l!. tro.QJ.us rnaculatus and Etroplus _suratensis . I . Descri p tion and po.:;;�;i ble evolution . Gopei a 1 972 ( �) : 8J4-8J8 .