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of Zizyphus nummularia, Leptadenia pyrotechnica, Tephrosia purpurea, ... Jan. Feb. Mar. Apr. May Jun. Jul. Aug. Sep. Oct. Nov. Dec. Undifferentiated. 26.6.
BREEDING

BIOLOGY

OF THE

INDIAN

RING

DOVE

IN

THE RAJASTHAN DESERT B. D. RANA

THE Indian Ring Dove, Streptopeliadecaocto,is one of the common columbidbirds of the Rajasthan Desert. Its preferred habitat is tracts

wheresuchtreesas Prosopiscineraria,Acaciatortilis,A. senegal,and Albizzialebbekgrowin appreciablenumbers.Its otherpreferrednestingsite is in the hedgesof Ingadelsis.It alsodwellsnear humanhabitations.Althoughspeciesof Streptopeliaare widely distributedin the Indian subcontinent, little work hasbeendoneon this genus.Except for Misra's (196061) observationson the reproductivecyclesin the Red Turtle Dove, S. tranquebarica,and in the Little Brown Dove, S. senegalensis, at Banaras, East India, almost no informationis availablein India on any aspectof breedingin S. decaocto.This paper deals with the breedingbehavior, male fecundity, female fertility, seasonalreproductivity,sex ratio, and body weightsof the ring dove. This study was carried out at Central ResearchFarm, Central Arid Zone ResearchInstitute, Jodhpur. Grassesabundanton the sandy plain

at the farm are: Eleusinecompressa, Cenchrusbiflorus,C. ciliaris, C. setigerus,Panicurn antidotale, P. turgidurn, Brachiaria rarnosa, and Dichanthiurn annulaturn. The herbs are representedby Tephrosiapurpurea, Heliotropiumstrigossum, Boerhaviadif/usa, Indigo/era cordi/olia, and Crotalaria burhia. The dominant shrubs are Ziz.yphus nurnrnularia and Capparisdeciduaand amongthe trees are Prosopiscineraria,Acacia tortilis, A. senegal,Azadirechta indica, and Albizzia lebbek. Crops of millet and pulsesare also grown at the Central ResearchFarm. MATERIAL

AI•D METItODS

At Jodhpur 200 ring doves were shot from August 1969 to July 1970. Soon after collectionthe doveswere weighed•dissected,and sexed. The gonadswere extracted and preservedin 10% formaldehyde. The measurementof testesand three largest developingoocytes from the left ovary were recorded in situ. The preservedtestes and ovary were weighedto 0.001 g in a semimicroMettler balanceand smearsfrom epididymis or from vas deferens were examined for the occurrenceof sperms. Field

observationson the nests,number of eggsand period of egg-laying,hatchingperiod, breedingsuccess, and growth of nestlingwere also recorded. RESULTS

Male fecundity.--In the present study, observationson reproduction aspectsof male ring doveswere limited to the examinationof smearsof vas deferens and epididymis and measurementsof testes. The adult 322

The Auk 92: 322-332. April 1975

April 1975]

Indian Ring Dove WITH

323

ß

MALE

V

MALE WITHOUT

SPERMS

o

FEMALE

WITH

X

FEMALE

WITH UNDIFFERENTIATED OVARY

ß

V

SPERMS OOCYTES

184.0 V

174.0

vV 164.0

ß

ßO V

1.54.0

Vo ß ß •/•oe• 0

144.0

V:V o ooø•ød•

vv ßßß

v



O

ß

I;34.0

I-

• IZ4.0

0

V

o

4:3

ß

v

o ß0 o

oß oo VoX ßV eV ß .. ßV ß 0Vo ß ßßßV ß VVvV ß o o%ß oV%•OO

ß

ø4

VcPøøøoo ß X•o VV Vo x o

%,,ø. o

ß

x

vV o ' ooo oø•.v ' oøø V0 oo o 0 xoø xX 7o o ø oeo ß

o

oxV X

>- 114,0

v

o

ß

V

XX

0 •3

104.0

94-0



84.0

V

o

o

74.0

ß

V

V

J

J

A

S

O

N

D

MONTHS

Fig. 1. Grossbody weight of doves,Streptopeliadecaocto,through 1969-70.

male doves were found to be fecund from February to October as evi-

dencedby the presenceof spermsin the smearsof epididymisand vas deferens(Fig. 1). Two peaks are evident in the frequencyof fecund adult male doves,March-April and August-September.It also appears that productionof spermsceasesfrom Novemberto January (winter season). Male ring dovesattain sexualmaturity when they are about 130 g in body weight, but during the monsoona few young dovesweighing 80 to 95 g alsohad spermsin the smears(Fig. 1). The right testesof ring doveswere found to be significantlyheavier than the left during breedingseason(at 1% level of probability) and during nonbreedingseasonat 5% level of probability. But it is worth

324

B.D.

RANA

TABLE

[Auk, Vol. 92

1

MEAN MONTIILY WEIGIIT AND LENGTli OF RIGtIT AND LEFT TESTES OF RING DOVE

Weight (g) Right --+ SE

Length (mm)

Left ñ SE

Right ñ SE

Left --+ SE

January February

0.0218 ñ 0.003 0.1943 ñ 0.05

0.0162 ñ 0.003 0.1553 ñ 0.02

6.41 ñ 0.53 11.10 ñ 0.96

6.39 ñ 0.73 12.45 ñ 0.83

March April

0.3499 ñ 0.6345 ñ

0.04 0.03

0.3053 ñ 0.03 0.4716 --+ 0.07

14.50 ñ 15.66 ñ

0.45 0.44

15.75 --+ 0.50 18.41 ñ 1.83

May June

0.6281 0.0653 0.5679 0.4713 0.5997

ñ ñ ñ ñ ñ

0.06 0.02 0.10 0.09 0.06

0.5282 ñ 0.05 0.0572 ñ 0.02

0.4868 -+ 0.06 0.4244 -+ 0.09 0.5593 ñ 0.05

17.61 8.50 16.41 14.30 17.00

0.50 0.66 0.83 1.18 0.41

19.60 8.75 18.08 17.20 19.20

October

0.1704 ñ

0.06

0.1600 ñ

10.91 -+ 1.04

November December

0.0880 ñ 0.07 0.0226 --+ 0.04

July August September

0.06

0.0817 ñ 0.06 0.0209 --+ 0.04

ñ ñ ñ ñ ñ

8.33 ñ 6.75 ñ

1.00 0.58

ñ -+ ñ ñ ñ

0.90 0.96 1.20 1.40 1.37

12.91 ñ

1.50

9.50 ñ 7.25 ñ

1.66 0.70

notingthat left testeswere foundto be significantly(P < 0.05) larger than the right testesthroughoutthe year (Table 1), as has beenobserved in HouseSwift, Apus affinis (Naik and Naik 1965). The meanpaired weightof testesdifferedsignificantly(P < 0.01) from monthto month. The mean monthly testis weight also showstwo peaks corresponding to frequencyof ovulation(Fig. 2). Female fertility.--The follicular size varied significantly(P < 0.05) from month to month. The mean monthly maximumdiameterof the folliclesvaries considerablyduring the year. The main peak occurs in May and the secondpeak in July and September.Similar trends are also revealed when the follicular size of all the female doves col-

lected during a year are groupedin sevenclassesat 1.5-mm intervals (Table 2). The ovary weight and length of oviduct also run parallel to the fol-

licularsizeandthetestesweights(Fig. 3). BREEDING BEHAVIOR

Nest site.--Ring dovesprefer to build their nestson trees like Pro-

sopiscineraria,Acacia tortills, and A. senegal,and in the hedgesof Ingadelsisspecies.The simpleflat nest is usuallysituatedat a height of 1.5 to 2.7 m on the branches, similar to the nestheightof the Turtle Dove,Streptopelia turtur, in England.The nestof S. decaocto is usually in the middle of the tree where the tree's top branchesconcealit. The selection of almostsimilarnestheightsby S. turtur in Englandand by S. decaocto in India probablyindicatesparallelevolutionary trendsin thesetwo species.

Nest composition.--Mostdoveslay eggsin freshly built nests but somebirds renovatethe old ones. The male ring dove plays an im-

April 1975]

Indian Ring Dove

325

e----e

LENGTH OF TESTES

O•o

WEIGHT

OF TESTES

X--.-X øJoFENALES (ADVANCED OVULATION• X•X

HEAN

TEHPERATURE

o

65

•. so

,• •o

.1i 2/ y. / •

•-•o







/ I

I



\V--'--v--.--v

JAN. FEB. MAR. APR. HAY JUNE JULY AUG. SEP. OCT. NOV. DEC.

Fig. 2. Mean monthly testesweight, length, temperature,and percentadult female ovulated

doves.

portant role in collectingthe nest building materials, like twigs mainly of Zizyphus nummularia, Leptadenia pyrotechnica, Tephrosia purpurea, and Calotropis procera. Thin grasseslike Eleusine compressa,and Aristida sp., wool of sheep, and sometimesits own feathers are used TABLE MONTItL¾

DISTRIBUTION

2

0]• FOLLICULAR SIZE 0]• RING DOVE AS PERCENT MONTItL¾ COLLECTION Months

of Year

Size class

(mm) Undifferentiated 0 to 1.5 1.6 to 3.0 3.1 to 4.5 4.6 to 6.0 6.1 to 7 5 7.6 to 9.0 9.1 to 10.5

Jan. Feb. Mar. Apr. May Jun. Jul. Aug. Sep. Oct. Nov. Dec. 26.6 28.6 55.5 25.0 23.0 6.7 -12.5 14.2 22.2 62.5 57.1 12.5 -77.0 33.3 40.0 25.0 57.1 22.2 12.5 66.6 42.8 75.0 60.020.0 60.0 50.0 12.5 --6.7 20.0 12.5

100 33.3 --

20.0

6.7

326

B.D. o--O

•-.I.:•,

TESTES

RANA

[Auk, Vol. 92

WEIGHT

e. FOLLICLE SIZE

X-•X.

WEIGHT OF LEFT OVARY

'.'

7-2

/i S.7

0.9, •r 0.8,

5.2 •

•-0.7,

.//

•'o,•

o

4.7

/

•.2•

• 0.54

t

o.•, /['/x•

0.1•

5.7•

fil/

' • •X/

'.

ie/

o,o, •



x

•.•

1.7

o

1.2

JAN, FEB. MAR. APR. MAY JUNE JULY AUG. SEE OC• NO• DEC. MONTHS

Fig. 3. Seconal variations in the mean testesweight, follicle s•e, and weight of ovary of ring dove.

for lining the nests. Sheep wool was found only in one out of about 54 nestsexamined.This particular nest was very near an experimental sheeppen. Althoughdoveswere not actually seentaking the wool, the neat arrangementof the wool fibers in a cluster under the eggsclearly indicatedthat the birdsusedthe woolasnestingmaterial. TABLE

3

SEASOtXTAL DISTRIBUTION OF CLUTCI• SIZE IN RING DOVE

Clutchsize

Total

Averagenumber

Months

1

2

3

number of clutch

April May July August September

2 2 1 3 2

11 3 2 12 17

2

13 5 3 15 21

22.0 7.3 4.5 24.7 38.5

1.84 1.60 1.66 1.80 2.00

October

1

1

-

2

2.7

1.50

Total

11

46

2

59

99.7

% of clutch size

18.7

78.0

3.3

-

Percentage of eggs

of eggsper clutch

-

-

-

April 1975]

Indian Ring Dove

327

Clutch period.--The first ring dove egg was found on 4 April 1970. The monthly clutch distributionshowsthe ring dove has two distinct breedingpeaks,i.e. one in April (22.0%) and the secondin August (24.7%) andSeptember(38.5%) (Table 3). The egg.--Egg weightsvaried from 5.9 to 8.6 g (average7.5 -+ 0.25 g). The mean length and breadth were 26.82 -+ 0.40 mm and 20.75 + 0.38 mm. The eggslaid in springwere significantly(P < 0.01) smaller than thoselaid in the monsoonperiod. Clutch size.--The clutch size varied from 1 to 3 (average 1.84). The frequencyof two eggsper clutchis 78.0% (Table 3), whereasonly twoclutches of threeeggswererecordedin September. Incubationand nestlingperiod.--The incubationperiodsduringspring and monsoonseasonsdiffered significantly(P < 0.01) from each other. The springperiod ranged from 18-19 days (mean, 18.5 -+ 0.15); the monsoon periodrangedfrom 10-17 days (13.3 + 0.57). Female doves feed their nestlingsuntil they leave the nest. The springnestlingperiodvariesfrom 14-18 days (16.0 -+ 0.90); the monsoon nestling period ranged from 12-17 days (14.0 -+ 0.43). These differences werenot significant. Breedingsuccess.--Of32 eggslaid during springonly 31.2% hatched and a low percentageof nestlingsfledged, 15.6% of total eggs laid (Table 4). The nestingsuccess duringthe monsoon periodwas higher. Of 77 eggslaid, 44% hatchedand a comparatively largenumber(39.0%) fledged.The nestlingsuccess betweenthe two breedingperiodswas not

significantly different(x2 (1) = 3.15,x2 (1) < 0.05: 3.84). Care and feeding of nestlings.--In the early morninghours during the first few days the femalesbroodthe young. Parentsfeed the young with cropmilk. Thereafterthey feedyoungmainlyuponBajra, Tephrosia purpurea, Brachiaria ramosa, Citrullus vulgaris, Til, seeds of Heliotropium strigossum,and termites, as revealed by the examination of cropsof five nestlings. Egg predation.--The House Crow, Corvus splendens,and the Indian

Roller, Coraciasbenghalensis, usuallyfeed on ring doveeggs. Predatory birdsdestroyed about68.7%of the eggsduringspringand 55.8%during the monsoon(Table 4). Only three eggsout of 109 were infertile. These lossesamount to 61.4% of the total eggslaid. After hatching 8.2%of thenestlings werelostto predatorybirds. SEx R^T•o

The sex ratio in monthly collectionsand on an overall yearly basis did not deviatesignificantlyfrom the normal50:50 hypothetical figures.

328

B. D. RANA TABLE

[Auk, Vol. 92

4

BREEDING SUCCESS OF RING DOVE DURING BREEDING SEASONS

Seasons Summer

No. of eggs laid 32

% of eggs hatched

% of eggs destroyed

31.2

68.7

(n .•- 10) • Monsoon

77

% of nestlings destroyed

44.1

(n = 34)

15.6

% fledged 15.6

(n --.• 22)

(n:

55.8

5.5

39.0

(n-----4)

(n = 30)

(n:

43)

5)

(n = 5)

x Figures in parenthesesindicate the actual numbers.

Still femalespredominatedin March, June,and September,and malesin January, February, May, and October to December (Table 5). The yearly sampleratio of malesto femaleswas 1:0.86. BoDY Wv. mI-iTs

The body weightsof 107 male and 93 female dovesvaried from 146 to 156 g in male dovesand from 138 to 154 g in females(Fig. 1). Apparently female doves acquire sexual maturity when they reach 130 g body weight. This is further borne out by the fact that the lightest femalecarryingeggsin the uterusweighed150 g. Most male dovesalso attain sexual maturity when their body weight reaches130 g, but smearsof a few doves weighing80-95 g showed sperms. Laboratory-rearedyoung reach 130 g body weight when they are about 2 monthsold. This suggests that youngfledgedin the spring breedingseasonmay breed in the followingmonsoonperiod. Statistical TABLE

5

MONTt•L¾ VARIATIONS IN TI-IE SEX RATIO OF RING DOVE

Month

Male

Female

% of male

11 10

3 3

78.5 76.9

March

6

8

42.8

April May

8 10

8 5

June July August September

10 10 5 ?

13 10 5 9

50.0 66.6 43.4 50.O 50.0 43.7

October

January February

10

5

66.6

November

6

5

54.5

December

8

6

57.4

107

93

53.5

Total

April 1975]

Indian Ring Dove TABLE

MEANMONThLY

January February

6

BODY Wr•0tI•S (0) 0• ADIrL• Ma• DURING EACH MONTI-I

Male

329

--+ SE

150.98 -+ 4.48 155.15 + 4.51

Female

Dows

--+ SE

150.66 + 4.00 147.36 + 6.29

March

150.40 +

April

149.68 + 4.19

145.20 + 4.07

May June July August September

154.64 156.42 146.36 149.50 151.08

142.70 145.43 142.15 153.20 138.61

October November December

155.50 + 3.03 156.46 -+ 5.37 148.78 + 5.19

+ -+ + -+ +

3.08

a•D F•a•r

3.36 3.90 4.42 3.09 3.54

151.80 +

2.85

+ + + + +

4.45 2.64 2.94 6.62 3.33

154.00 + 143.63 + 145.00 +

3.75 4.41 3.50

analysis revealed that male doves average significantly heavier than femaledoves(Table 6). Seasonalvariations.•Neither the mean monthly body weight of male nor of female doves was found to vary significantlyfrom month to month. Body weightswere lowest during July and Septemberbecause of an influx of lighter adult doves in the collection for these months (Table 6). Thereafter they gainedweight and reachedthe peak during postmonsoonand winter seasons,which may be due to accumulation of body fat as hasbeenobservedin the Wood Pigeon,Columbapalumbus (Murton 1958). Distribution of body weightsin the sample.--The body weights of all dovesare groupedin four classesarrangedat 30 g intervals. The subadult classes,70 to 100 g and 101 to 130 g are distributed from April to December among male doves, whereasthe female sub.adultswere collectedonly during June, July, and October (Table 7). It is difficult to explain why female subadults should be fewer than males. The proportion of subadult doves collected during the earlier half of the year is lower than that in the latter half, probably because of the low egg-layingrate during the former period (Table 3). It may alsoindicatethat nestlingmortality during the first 6 monthsof the year is high becauseof poor vegetation condition, adverse climatic factors,andpoornourishing conditionof mothers. DISCUSSION

The ring doves' breeding seasonlasts from March to October, as evidencedby the presenceof spermsin male birds, seasonalfluctuations in testisweight, rate of ovulation,and actual egg-laying.Two distinct peaks are evident in the birds' egg-layingactivities, the first peak in

330

B.D. TABLE

MONTItLY

RANA

[Auk, Vol. 92

7

DISTRIBUTION OF WEIGItT CLASSES OF MALE AND FEiVIALE DOVES EXPRESSED AS PERCENT or MONTIILY COLLECTION

Weight of classes(g)

Males 70 to 100 101 to 130 131 to 160 161 to 190

Females 70 to 100 101 to 130 131 to 160 161 to 190

Months ofyear

Jan. Feb.

72.7 70.0 27.3 30.0

Mar. Apr. May Jun. Jul. Aug. Sep. Oct. Nov. Dec. --83.3 16.7

--66.6 100.0 100.0 33.3 ---

-12.5 75.0 12.5

9.1 -9.1 -54.6 70.0 27.2 30.0

25.0 20.0 8.3 -58.3 80.0 8.3

--

87.5 100.0 12.5 --

6.6 7.6 33.3 84.6 60.0 7.6 --

-27.3 14.3 -25.0 --12.5 75.0 54.5 66.4 75.0 18.2 18.2 12.5 28.5

60.0 40.0

88.8 11.1

57.1 66.6 14.3 33.3

87.4 12.5

the spring and the other during the monsoon. During both seasons, green food is comparativelyabundantin the desert, much more during the monsoon,when a significantly(X2 (1) = 22.9, P < 0.001) higher rate of egg-layingis manifested.The hatchingsuccessand survival of young birds is also of a higher order, after the monsoonbreedingpeak. Such a dependence for the maintenanceof maximumbreedingresponse to greenpastureshas alsobeen reportedfor the Wood Pigeonin London (Baker 1938, Lack 1950, Moreau 1950, Murton and Isaacson 1962, Murton et al. 1963,Lofts et al. 1966). It is also interestingto find that the breedingseasonof some of the columbidslasts from March to October in many countries (Table 8), irrespective of the wide variation with respect to mean temperatures, latitude, and precipitation. The northwestAustralian birds also start breedingin February (Augustof southernhemisphere)and the breeding activity exhibits two peaks during March-April (September-Octoberof TABLE

8

BREEDING SEASONS OF COLUIvIBIDAE FAIvIILY

Spp. of the bird Ring dove Stock dove

Locality Jodhpur, Rajasthan Oxford, London

•t

British Trust for

t• •t

Ornithology, nest records Celles,Belgium Sevendonk,Belgium

W•odPigeon East Anglia, London Carlton and Cambs

Breeding season

Authority

March to October

Present study

March to October

Campbell 1951

March to October

Robbins in litt.

February to September Delmee 1954 March to September Paulussen 1953 March

to October

May to October

Murton

1958

Murton and Isaacson

1964

April 1975]

Indian Ring Dove

331

the southern hemisphere) and during August-September(FebruaryMarch of southernhemisphere). ACKNOWLEVO•E•TS

The author is grateful to T. R. Mehta, Director, and G. C. Taneja, Head of Division, for providing facilities. ! am also indebted to Ishwar Prakash, Animal Ecologist, for his constantguidance. Thanks are due to Pulak Kumar Ghosh, Animal Physi~ ologist,for examiningthe manuscriptand for helpful suggestions. SUMMAlaY

Ring doves were collectedby shootingin every month during 196970 at the farm of Central Arid Zone ResearchInstitute, Jodhpurin the Rajasthan Desert.

Male doveswere found to be fecund from February to October. The fecundityin maleswas attained at 130 g body weight,but a few young dovesweighing80 to 95 g exhibit spermsin smears. The testesweights and percentfecundityof adult male doveswere broadly parallel to those of the adult advancedovulatedfemale and frequencydistributionof egg laying. The right testes of adult doves collectedover the year were found to be heavier than the left in both breedingand nonbreeding seasons, the differencesbeingsignificantat 1% and 5% level respectively. The averagetestesweightswere also iound to vary significantly(P < 0.01) from month to month. Ring dovesprefer to build their nestsat a height of 1.5 to 2.7 m on trees like Prosopiscineraria,Acacia tortills, A. senegal,and hedgesof Ingadelsisspp. The simpleflat nest is usuallymade up of thin grasses and small tree twigs. The egg weightrangedfrom 5.9 to 8.6 g (average7.5 g). The clutch size varied from one to three (average1.84). Of the total eggslaid 69.6% were destroyedby predatory birds. The eggs laid in monsoon seasonwere significantly(P < 0.01) larger than thoselaid during spring period. The average incubation and nestling period were 15.9 and 15.0 days respectively. The proportionof male and female dovescollectedover the year do not deviatesignificantlyfrom the hypothetical50:50 ratio. The ring dove breeds from March to October as evidencedby seasonal fluctuationsin testes weights,percent adult fecund males, rate of ovulation, and egg-laying. The two peaks in egg-layingcorrespond to the spring seasonand to the monsoonperiod when green forage is available.

The male doves were found to be significantly heavier than the fe-

males. Body weightsof doveswere lowest during July and September,

332

B.D.

RANA

[Auk, Vol. 92

thereafter they gain body weightsand reach a peak during postmonsoon and winter

seasons. LITERATIJRE CITED

BAIrEI•, J. R.

1938. The evolution of breeding seasons. Pp. 161-177 in Evolution

(G. R. de Beer, Ed.). London, Oxford Univ. Press. CAXVr•BELL, B. 1951. A colony of stock doves. Bird Notes 24: 168-176. DEL•EE, E. 1954. Douze anees d'observationssur le comportement du pigeon colombin(Columba oenasL.). Le Gerfaut 44: 193-259. LAc•:, D. 1950. Breeding seasonsin the Galapagos. Ibis 92: 268-278. Lofts, B., R. K. M•JRTO•, A•D N.J. WEST WOOD. 1966. Gonad cycles and the evolution of breeding seasonin British Columidae. J. Zool. Soc. London 150: 249-272.

MISRA,A.B.

1960-61. The annual reproductivecyclesof someIndian birds, part 1.

J. Sci. Res. (B.I-I.U.) 11: 343-385. MOaEAXJ,R. E. 1950. The breeding seasonsof African birds, land birds. Ibis 92: 223-267.

M•JaTO•, R. K.

1958. The breeding of Wood Pigeon populations. Bird Study 5:

157-183.

M•JaTO•, R. K., A•D A. J. Is^Acso•. 1962. The functional basis of some behavior in the Wood Pigeon, Columba palumbus. Ibis 104: 503-521. M•JaTOX,R. K., AI•IDA. J. ISAACSOI•I.1964. Productivity and egg predation in the Wood Pigeon. Ardea 52: 30-47.

M•JRTO•,R. K., A. J. ISAACSO•, A•D N.J. WESTWOOD. 1963. The food and growth of nestling Wood Pigeons in relation to the breeding season. Proc. Zool Soc. London

141:

747-782.

NASa, R. M., A•D S. NASa. 1965. Studieson the House Swifts, Apus affinis, G. C. Grey IV. Gonadal cycle. Pavo 2: 77-88. PA•J•XJSSE•, W. 1953. Over de broedselsvan de Bosen Holduiven. (Columba palurebusL. en C. oenas). Le Gerfaut 43: 128-131.

B. D. RANA,Animal StudiesDivision, Central Arid Zone Research Institute, Jodhpur (Rajasthan), India. Accepted1 April 1974.