Reproduction in Captive and Wild Dingoes (Canis familiaris dingo ...

Wildl. Res., 1992, 19, 195-209
Reproduction in Captive and Wild Dingoes
(Canis familiaris dingo) in Temperate
and Arid Environments of Australia
P. C. catling? L. K. corbettB and A. E. ~ewsome*
A CSIRO Division of Wildlife and Ecology, P.O. Box, 84,
Lyneham, Canberra, A.C.T. 2602, Australia.
CSIRO Division of Wildlife and Ecology, P.M.B. 44,
Winnellie, Darwin, N.T. 0821, Australia.
Abstract
The dingo (Canis familiaris dingo) had one breeding period per year. Most matings took place in
April/May and most births in June/July. All males in their first year exhibited a testis response similar
to that in older males, but the peak in that response was reached two months later and the prostate
reached only half the weight of the prostate of old males. Some older females did not produce young
and only a small percentage of females bred in their first year. Crossbreed canids [dingo xferal dog
(Canis familiaris familiaris)] did not follow the same reproductive pattern as the dingo. Several testis
parameters did not show the marked seasonal variation seen in the dingo. Also, crossbreeds had larger
litters than dingoes and some bred throughout the year. A major difference in reproductive response
was detected between flush and drought periods in arid central Australia. Males and females responded
one month later during drought periods. During drought, fewer older females and no first-year females
bred and males demonstrated a reduced and delayed reproductive response. Social constraints on
reproduction have been shown in young dingoes, but in this study a lack of food due to drought may
have had a greater influence.
Introduction
The dingo (Canis familiaris dingo) is the largest terrestrial predator in Australia (mean
weight 15 kg) (Corbett 1985) and is distributed over most of the mainland. It is derived
from the Indian wolf (Canis lupus pallipes) (Clutton-Brock et al. 1976) and is closely related
to domestic dogs (Canis familiaris familiaris) (Newsome et al. 1980; Newsome and Corbett
1982), with which it readily crossbreeds (Newsome and Corbett 1985).
Wild canids, e.g. wolves (Canis lupus lupus) (Mech 1970; Zimen 1975), African basenji
(C. f. familiaris) (Scott and Fuller 1965) and pariah dogs (C. f. familiaris) (Oppenheimer
and Oppenheimer 1975), breed once each year whereas domestic dogs may breed twice per
year (Harrop 1960). Preliminary reports on the dingo indicated a single breeding season
between April and June, and for crossbreeds (dingox domestic dog) a breeding season
similar to that of domestic dogs (Newsome et ai. 1973; Catling 1979).
The dingo is becoming well understood, e.g. ancestry (Macintosh 1975; Corbett 1985),
identity (Newsome et al. 1980; Newsome and Corbett 1982; Jones 1990), diet (Whitehouse
1977; Newsome et al. 1983a, 1983b; Robertshaw and Harden 1985; Corbett and Newsome
1987; Marsack and Campbell 1990), social behaviour (Corbett and Newsome 1975; Corbett
1988), home range and movements (Thomson 1984; Harden 1985), control (Thomson 1986),
but no detailed studies of reproduction have been published. Jones and Stevens (1988)
examined reproduction in wild canids from Victoria, but they did not separate dingoes
and crossbreeds.

P. C. Catling et al.
In this paper we examine and compare the breeding biology of captive and wild dingoes
in temperate south-eastern Australia and in arid and submonsoonal regions of central
Australia. We also examine the breeding biology of captive and wild dingoes and crossbreeds
in south-eastern Australia. These data are necessary to ascertain the breeding potential of
the dingo both for conservation and management in pastoral areas.
Methods
Study Areas
Four study areas were established, one in submonsoonal and two in arid central Australia (A, B
and C, Fig. l), and one in temperate south-eastern Australia (D, Fig. 1). Habitats in central Australia
are described by Corbett and Newsome (1987) and Newsome (1983), habitats in temperate Australia by
Newsome et al. (1983a, 19836).
p
Fig. 1. Study regions in central Australia (Areas A, B and C) and the eastern highlands (Area D).
Field Samples and Laboratory Analyses
In central Australia between 1966 and 1976, nearly 2000 dingoes were foot-trapped or shot, and
biological material was collected at post-mortem examination. In the eastern highlands between 1969
and 1975, 530 dingoes were collected by CSIRO and the 25 dingo trappers employed by the dingocontrol
organisations in the region. Testes, prostate glands and uteri were weighed and samples of each
were preserved in 10% buffered formalin for histology. The number of placental scars or foetuses in
uteri were recorded. Vulva1 tumescence and lactation were also recorded. Cleaned skulls were used to

Reproduction in Captive and Wild Dingoes
estimate age and to identify dingoes, dogs or crossbreeds (Newsome et al. 1980; Newsome and Corbett,
1982, 1985). Testis samples were embedded in paraffin wax, sections cut at 8 pm and stained with
haematoxylin and eosin. The number and type of cells in the spermatogenic layer, the presence or
absence of sperm and the tubule diameter were recorded for 10 circular tubules per testis. A Student's
t-test was used to compare the means between two periods (January-June, July-December).
The ages of wild pups were estimated from the growth curves of known-age animals (Catling et al.
1991), and birth and mating dates were extrapolated from them. Ages of foetuses were estimated from
measurements of foetuses from known-age domestic dogs (Harrop 1960). Young animals were defined
as animals less than 1 year old and older animals were classified as adults.
Field samples in central Australia were collected during drought and flush years. Flush years are
those favouring pasture growth (cf. Corbett and Newsome 1987) and are calculated from rainfall
(Newsome 1966). Seasons varied between areas but 1970, 1971 and 1972 were drought years in all areas.
Captive Colonies
Colonies of dingoes, domestic dogs and crossbreeds were established at Alice Springs and Canberra
to record dates of matings and births, vulva1 tumescence, litter size, coat colour, sex of pups and time
of lactation and suckling. The domestic breeds used were mainly Australian cattle dogs (blueheelers),
but Australian sheepdogs (kelpies), labradors, a Dobermann pinscher and a beagle-style hound were
used also. Samples of semen were collected by digital manipulation into an insulated glass container,
the volume (mL) measured, and an aliquot taken and mixed with a formalin-saline buffer solution
at a dilution of 1: 100. One drop was placed in a haemocytometer cell, covered with a coverslip,
examined under a miscroscope (240 x), the sperm counted in 5 of the 25 cells and multiplied by 5000
to give an estimate of number of sperm per mm3.
In both colonies, male dingoes were placed with ovulating female domestic dogs and crossbreeds at
various times throughout the year, including the dingoes' non-breeding season, to test whether they
would mate and produce offspring.
Results
Males
Prostate and testis weight
The mean monthly prostate weights for males in central Australia were at lowest levels
between September and January (Fig. 2). Then followed a rapid 6-fold increase for adults
and 12-fold increase for young animals to a sharp peak in April/May. However, young
animals had lower weights than adults. The data for dingo and crossbreeds from the eastern
highlands were lumped; nevertheless, a similar trend was observed.
The mean monthly testis weights followed similar trends to those for prostate weights
but peaks were less pronounced (Fig. 2).
Testis histology
Mean monthly changes in tubule diameter, the number of tubules with sperm and the
number of cells in the spermatogenic layer are shown in Fig. 3a-c, respectively. Values for
young dingoes and crossbreeds were either zero or very low for all three parameters in
September. However, they began to increase rapidly in January/February and remained
high until August.
Adult dingoes had relatively low values for all three parameters between July and
December but these increased rapidly to relatively high values between January and June.
Differences in values between the two periods were significant for adult central Australian
dingoes (January-June, n =204; July-December, n = 145) for tubule diameter (t = 10.91,
P

P. C. Catling et al.
Central Australian dingoes
(a) Prostate weight
Eastern highlands dingoes and crossbreds
(b) Test$ weight
r
21 yr old 62 17 19 24 36 38 29 43 66 78 51 19
0.05).
Between July and December, eastern highlands adult dingoes (n = 32) had significantly
higher values for tubule diameter (t=2.42, P

Reproduction in Captive and Wild Dingoes

P. C. Catling et al.
-
3
E 4-
C
z
- Q
In
- 100 .;j
8
5 2 - %
0,
- 5 -
f
z
0- - 0
S O N D J F M A M J J A
NurnberofSperm 4 4 10 4 8 14 10 13 22 9 19 21
SemenVolurne9 11 16 9 8 16 10 15 22 9 20 22
Month
Fig. 4. Volume (mL) of semen (0) and the number of sperm per mm3 (X lo3) of
semen (A) in adult dingoes from central Australia. Values are F-+ s.e., with the number
of samples at the bottom of the graph.
Adult dingoes in the eastern highlands (34%) were in heavy tumescence over the same
period, as were all crossbreeds (33%) (Fig. 54.
Pregnancy, sex ratios and litter size
In the wild, foetuses were recorded in 9% of young and 32% of adult females in central
Australia between May and July, and in one adult female in August (Fig. 5b). The average
number of foetuses for 44 females was 5.70 f 0.22. Eastern highlands dingoes were pregnant
between May and August, crossbreeds between April and July (Fig. 5b).
The sex ratio of pups from wild central Australian dingoes (males: females) was 1 : 0.94;
and that for captive central Australian and eastern highlands dingoes was 1 :0.92 and
1: 1.31, respectively. For captive central Australian and eastern highlands crossbreeds the
respective values were 1: 1.37 and 1 :0.92. Mean litter sizes also were similar (Table 1)
except in the eastern highlands colony, where crossbreeds had significantly larger litters
than dingoes (t=2.48, n=47, P

Reproduction in Captive and Wild Dingoes
Central Australian dingoes
(a) Tumescence
""I
Eastern highlands dingoes and crossbred
(b)
1
Pregnant
0-, , , ,
C1 yrold 6 4 2 3 24 20 32 41 22 25 10 8
>1 yr old49 10 14 24 37 34 35 47 22 60 35 21
-"1:
C
2
(c) Lactation
1
Dingo 8 7 15 14 14 13
Crossbred 8 9 5 14 22 1 1
S O N D J F M A M J J A
clyrold6 4 2 3 18 19 2936 19 25 10 8
>1 yr old36 8 21 24 33 34 27 52 33 61 47 19
Month
SO ND JF MA MJ JA
Dingo 8 8 15 14 12 16
Crossbred6 10 5 12 15 14
Month
Fig. 5. Time of (a) tumescence, (b) pregnancy and (c) lactation in dingoes from central Australia
less than 1 year old (A) and more than 1 year old (0); dingoes from the eastern highlands (0) and
crossbreeds from the eastern highlands (a). The number of animals is shown at the bottom of the graph.
Uterine weight
The mean uterine weight of adult dingoes from central Australia was less than 20 g from
October to March (Fig. 6). For most adults (73.5%), weights began to rise in April and
reached a peak of about 115 g in June, after which they fell quickly. Almost half (46%) of
young dingoes showed a similar pattern, although the peak of about 60 g was attained
in May. Females with a uterine weight of less than 20 g between April and August were
considered not to have bred (adults 25%; young 54%) (Fig. 6). Data were few from the
eastern highlands, but they followed the same trend. All animals with a uterine weight of
more than 50 g were found between March and June (dingo, n = 1; crossbreed, n=5).

P. C. Catling et a[.
Fig. 6. Changes in uterine weight
(g) in female dingoes from central
Australia more than 1 year old
(0, W) and less than 1 year old
(A,A). From April to August W
indicates dingoes more than 1 year
old that did not breed and A
indicates dingoes less than 1 year
old that did not breed. Values are
Yks.e.; the number of animals is
shown above or below the symbol.
Month
Time of Mating
Captive colonies
In central Australia matings between dingoes occurred between March and July, with
most (77%) in April and May. In the eastern highlands matings between dingoes occurred
between April and July, with most (7070) in April and May. Crossbreed and domestic
females mated only in March and April in central Australia whereas they mated throughout
the year in the eastern highlands (Fig. 7).
In the central Australian colony a male dingo and a female domestic dog (Blue Heeler)
in oestrus were placed together for several weeks in November and again in December.
Fig. 7. The number of matings in each
month in (a) the central Australian colony
and (b) the eastern highlands colony.
Mating between dingoes is unhatched and
that between a dingo and a crossbreed or
domestic female is hatched.
Month

Reproduction in Captive and Wild Dingoes
No mating behaviour by the male was observed and the female did no become pregnant.
The male had low semen volume and a low sperm count similar to other males housed with
other non-oestrous females (cf. Fig. 4). The same pair mated in the following March and
five pups were whelped. In the following October, when they were housed together again,
no sexual behaviour was observed and the male again had low semen and sperm values.
In the wild
Most matings between wild dingoes in central Australia were estimated, from the age of
pups and foetuses, to occur between March and July. However, drought delayed the time
of mating by several months (see below).
Effect of Flush and Drought on Reproduction
Testis weight and testis histology
Testis weight and testis histology differed significantly between drought and flush periods.
Testis weight reached a peak between February and April during flush periods compared
with a sharp peak in May during drought (Fig. 8). Mean monthly testis weight was significantly
lighter during drought (t = 2.38, n = 484, PC O.02), as were prostate weights
(t = 5.35, n = 169, P< 0.001). Similarly, mean monthly tubule diameters were smaller
(t=2.34, n=349, P

P. C. Catling et al.
Uterine weight
Mean monthly uterine weights of adults during drought were lighter and peaked in July,
a month later than during flush (Fig. 9a). In young dingoes there was virtually no increase
in uterine weight during drought compared with a substantial increase in May and June
during flush periods (Fig. 9b). Overall, uterine weights of young dingoes were approximately
half that of adults.
(a)
0
Flush 36 13 18 12 15 15 13 37 15 38 22 18
Drought 26 2 12 18 13 17 29 23 16 33 15 8
-
0
60
E
cn 40
.-
P
a
.- C
20
z
5
Fig. 9. Changes in uterine weight (g)
(F+s.e.) during drought (A) and flush (0)
for (a) dingoes more than 1 year old and
(b) less than 1 year old. The number of
animals is shown at the bottom of the
graph.
O S O N D J F M A M J J A
Flush 3 12 16 16 31 17 28 37 18 7 3 4
Drought1 1 3 4 15 10 12 6 8 17 7 0
Month
Placental scars
The above differences between adults and young dingoes were also reflected in the
number of placental scars recorded during drought and flush periods. No placental scars
were recorded in young dingoes during drought, and fewer adults had scars in drought,
significantly so for Area C (X2=6.02, P

Reproduction in Captive and Wild Dingoes
Table 2. Percentage of adult and juvenile females with placental scars and the number of scars
Q+s.e.) during drought and flush periods in central Australia
Flush
Drought
Area A Area B Area C Area A Area B Area C
Juveniles (less than 1 year old)
Total sampled 13 47 45 9 20 33
% with scars 38 6 4 0 0 0
Number of scars 6.0k0.6 4.0k0.6 5.5 0 0 0
Adults (more than 1 year old)
Total sampled 68 40 35 10 27 119
% with scars 63 55 46A 40 37 24A
Number of scars 4.9k0.1 4.9k0.4 5.4k0.3 5.0k0.8 5.6k0.6 5.1+_0.3
- - -
A Significant (P

P. C. Catling et al.
reproductively successful as older males. Also, the testis parameters of young males peaked
two months later than those of adults. Females in their first breeding season showed similar
trends to older females. However, only 30-40% raised pups compared with 60-70% of
older females.
Crossbreeds from the eastern highlands did not show the same pattern as that for
dingoes. There was no significant difference in testis histology throughout the year and one
female was found to be lactating in November-December. Corbett (1974) and Jones and
Stevens (1988) found that a small percentage of wild canids from the eastern highlands
produced litters outside the dingo breeding season. These were most likely crossbreeds.
Jones and Stevens (1988) also found indications of a testicular cycle in wild canids which
may have been clearly defined if dingoes and crossbreeds could have been identified.
Certainly, in the eastern highlands colony, crossbreed and domestic females bred all year.
The most notable difference in reproductive response in dingoes was observed in central
Australia between flush and drought periods. During drought periods the testes responded
several months later than during flush. Similarly, for females, uterine weight increased
substantially in May/June during flush times but not until July/August during drought.
During drought many adult female dingoes did not breed and all first-year females failed
to breed, whereas in flush years some first-year females had placental scars and many had
uterine weights of about 50 g but none reached over 100 g, which was common for many
older females. Area A had better quality food than Area B, and Area B had better quality
food than Area C during drought and flush (Corbett, unpublished data), which was reflected
also in the number of females with placental scars, there being more in Area A than
Areas B or C.
In the central Australian captive colony most first-year females bred and matings began
at the same time as found in the wild during flush periods. The time observed in the colony
and the greater success of first-year females may have been related to the provision of
adequate food and water. Corbett (1988) concluded that the major mechanism suppressing
successful breeding in dingoes is infanticide by dominant females. His study was conducted
in an enclosure with the provision of adequate food and water. This study supports Corbett's
(1988) conclusion but only during good environmental conditions because during periods of
drought and low food availability first-year females did not become pregnant.
In the wild, female wolves do not breed before 22 months of age (Young 1944; Pulliainen
1965; Rausch 1967), which generally is true for captive females also (Murie 1944; Pulliainen
1965; Rabb et al. 1967; Lentfer and Sanders 1973), although some have bred or shown
reproductive activity at 9-10 months of age (Medjo and Mech 1976), which may also be due
to the provision of adequate food and water.
In the Alaskan wilds, multiparous wolves breed earlier than first breeders (Rausch 1967);
in a study of captive wolves (Zimen 1975) the oldest female came on heat first, followed by
another adult two weeks later, and then a 6-month-old female. Corbett (1988) found this
sequence in a pack of captive dingoes where the oldest female was the dominant female and
always came into oestrus first. In both wolf and dingo packs, wild and captive, usually
only one litter per pack is successfully raised, usually that of the dominant pair (wolves:
Harrington et al. 1982; Packard et al. 1983; dingoes: Corbett 1988), implying reproductive
suppression of other females in the pack (wolves: Woolpy 1968; Mech 1970; Fox 1971;
Zimen 1975; Haber 1977; Peterson 1978).
In coyotes (Canis latrans) inadequate food and intraspecific strife may result in death and
may severely reduce reproduction the following year (Gier 1975). Bertram (1973) found that
reproduction in lions (Panthera leo) was profoundly influenced by behavioural factors but
little by food availability. Corbett (1988) demonstrated social constraints on reproduction
in dingoes. However, in our study during drought fewer old females bred, males demonstrated
reduced and delayed reproductive response and a11 first-year females did not breed.
It appears that a lack of food due to drought may have a greater influence on reproduction
than social constraints.

Reproduction in Captive and Wild Dingoes
Acknowledgments
We thank the many people, including pastoral lessees, who assisted both with the
captive colonies and the fieldwork. Special thanks go to Messrs P. Hanisch, H. Wakefield,
R. Hodder and G. Bartram who collected most of the samples in central Australia, and
R. J. Burt and J. Lemon for sampling in the eastern highlands. The expertise of R. J. Burt,
P. Hanisch, J. Lemon and H. Wakefield is acknowledged for histological preparations in
the laboratory, especially Messrs H. Wakefield and R. J. Burt who also assisted greatly with
analyses. Mr R. J. Burt also drew the figures. Dr I. Eberhard was involved in establishing
the eastern highlands colony, as was Mr A. Shipway with the central Australian colony.
Dr B. Green read an early draft. We are grateful also to the late Mr G. Douglas and his
dingo trappers from the Lands Department in Victoria for collection of much of the material
from the eastern highlands. In central Australia, the Northern Territory Government kindly
allowed us to house the captive colony at the Arid Zone Research Institute in Alice Springs.
Mr Bruce Parker donated blue-heelers to both colonies; Messrs Bryden Ganley and Bob
Millington donated domestic dogs and the Allen Brothers supplied the initial dingoes for the
central Australian colony. Mrs H. Mason typed the early drafts and the final manuscript.
The study was conducted under grants CS8S and CS17 from the Australian Meat Research
Committee.
References
Ables, E. D. (1975). Ecology of the red fox in North America. In 'The Wild Canids: their Systematics,
Behavioral Ecology and Evolution'. (Ed. M. W. Fox.) pp. 216-36. (Van Nostrand Reinhold Co.:
New York.)
Bertram, B. C. R. (1973). Lion population regulation. East African Wildlife Journal 11, 215-25.
Catling, P. C. (1979). Seasonal variation in plasma testosterone and the testis in captive male dingoes,
Canis familiaris dingo. Australian Journal of Zoology 27, 939-44.
Catling, P. C., Corbett, L. K., and Westcott, M. (1991). Age determination in the dingo, Canis
familiaris dingo. Wildlife Research 18, 75-83.
Clutton-Brock, J., Corbet, G. B., and Hills, M. (1976). A review of the family Canidae, with a
classification by numerical methods. Bulletin of the British Museum (Natural History) Zoology
29, 119-99.
Corbett, L. K. (1974). Contributions to the biology of dingoes (Carnivora:Canidae) in Victoria.
M.Sc. Thesis, Monash University, Melbourne.
Corbett, L. K. (1985). Morphological comparisons of Australian and Thai dingoes: a reappraisal of
dingo status, distribution and ancestry. Proceedings of the Ecological Society of Australia 13,
277-91.
Corbett, L. K. (1988). Social dynamics of a captive dingo pack: population regulation by dominant
female infanticide. Ethology 78, 177-98.
Corbett, L. K., and Newsome, A. E. (1975). Dingo society and its maintenance: a preliminary analysis.
In 'The Wild Canids: their Systematics, Behavioral Ecology and Evolution'. (Ed. M. W. Fox.)
pp. 369-79. (Van Nostrand Reinhold Co.: New York.)
Corbett, L. K., and Newsome, A. E. (1987). The feeding ecology of the dingo. 111. Dietary relationships
with widely fluctuating prey populations in arid Australia: an hypothesis of alternation of predation.
Oecologia 74, 215-27.
Fox, M. W. (1971). 'Behavior of Wolves, Dogs and Related Canids.' (Harper and Row: New York.)
Gier, H. T. (1975). Ecology and social behavior of the coyote. In 'The Wild Canids: their Systematics,
Behavioral Ecology and Evolution'. (Ed. M. W. Fox.) pp. 247-62. (Van Nostrand Reinhold Co.:
New York.)
Haber, G. C. (1977). Socio-ecological dynamics of wolves and prey in a subarctic ecosystem. Ph.D.
Thesis, University of British Columbia, Vancouver.
Harden, R. H. (1985). The ecology of the dingo in north-eastern New South Wales. I. Movements and
home range. Australian Wildlife Research 12, 25-37.

P. C. Catling et al.
Harrington, F. H., Pacquet, P. C., Ryon, J., and Fentress, J. C. (1982). Monogamy in wolves: a review
of the evidence. In 'Wolves of the World: Perspectives on Behavior, Ecology and Conservation'.
(Eds F. H. Harrington and P. C. Pacquet.) pp. 209-32. (Noyes Publications: Park Ridge, New
Jersey, U.S.A.)
Harrop, A. E. (1960). The physiology of reproduction in the dog and bitch. In 'Reproduction in the
Dog'. (Ed. A. E. Harrop.) pp. 64-86. (BalliCre, Tindall and Cox: London.)
Jones, E. (1990). Physical characteristics and taxonomic status of wild canids, Canis farniliaris, from
the eastern highlands of Victoria. Australian Wildlife Research 17, 69-81.
Jones, E., and Stevens, P. L. (1988). Reproduction in wild canids, Canis farniliaris, from the eastern
highlands of Victoria. Australian Wildlife Research 15, 385-94.
Jones, R. C. (1989). Reproduction in male Macropodidae. In 'Kangaroos, Wallabies and Ratkangaroos.
Vol. 1'. (Eds G. Grigg, P. Jarman and I. Hume.) pp. 287-305. (Surrey Beatty and Sons
Pty Ltd: Australia.)
Lentfer, J. W., and Sanders, D. K. (1973). Notes on the captive wolf (Canis lupus) colony, Barrow,
Alaska. Canadian Journal of Zoology 51, 623-7.
Macintosh, N. W. G. (1975). The origin of the dingo: an enigma. In 'The Wild Canids: their
Systematics, Behavioral Ecology and Evolution'. (Ed. M. W. Fox.) pp. 87-106. (Van Nostrand
Reinhold Co.: New York.)
Marsack, P., and Campbell, G. (1990). Feeding behaviour and diet of dingoes in the Nullarbor region,
Western Australia. Australian Wildlife Research 17, 349-57.
Mech, L. D. (1970). 'The Wolf: the Ecology and Behavior of an Endangered Species.' (Natural History
Press: New York.)
Medjo, D., and Mech, L. D. (1976). Reproductive activity in nine- and ten-month-old wolves. Journal
of Mammalogy 57, 406-8.
Murie, A. (1944). The wolves of Mount McKinley. U.S. National Park Service, Fauna Series 5,
Washington, D.C.
Newsome, A. E. (1966). Estimating the severity of drought. Nature 209, 904.
Newsome, A. E. (1983). The grazing Australian marsupials. In 'Tropical Savannas'. (Ed. F. Bourliere.)
pp. 441-61. (Elsevier Scientific Publishing Co.: Amsterdam.)
Newsome, A. E., and Corbett, L. K. (1982). The identity of the dingo. 11. Hybridization with domestic
dogs in captivity and in the wild. Australian Journal of Zoology 30, 365-74.
Newsome, A. E., and Corbett, L. K. (1985). The identity of the dingo. 111. The incidence of dingoes,
dogs and hybrids and their coat colours in remote and settled regions of Australia. Australian
Journal of Zoology 33, 363-75.
Newsome, A. E., Corbett, L. K., Best, L. W., and Green, B. (1973). The dingo. Australian Meat
Research Committee Review 14, 1-1 1.
Newsome, A. E., Corbett, L. K., and Carpenter, S. M. (1980). The identity of the dingo. I. Morphological
discriminants of dingo and dog skulls. Australian Journal of Zoology 28, 615-25.
Newsome, A. E., Catling, P. C., and Corbett, L. K. (1983~). The feeding ecology of the dingo. 11.
Dietary and numerical relationships with fluctuating prey populations in south-eastern Australia.
Australian Journal of Ecology 8, 345-66,
Newsome, A. E., Corbett, L. K., Catling, P. C., and Burt, R. J. (1983b). The feeding ecology of the
dingo. I. Stomach contents from trapping in south-eastern Australia, and the non-target wildlife also
caught in dingo traps. Australian Wildlife Research 10, 477-86.
Oppenheimer, E. C., and Oppenheimer, J. R. (1975). Certain behavioural features in the pariah dog
(Canis familiaris) in West Bengal. Applied Animal Ethology 2, 81-92.
Packard, J. M., Mech, J. D., and Seal, U. S. (1983). Social influences on reproduction in wolves.
In 'Wolves in Canada and Alaska: their Status, Biology and Management'. (Ed. L. N. Carbyn.)
pp. 78-85. Canadian Wildlife Service Report No. 45, Ottawa Service.
Peterson, R. 0. (1978). Wolf ecology and prey relationships on Isle Royale. National Park Service
Scientific Monograph 11, 1-210.
Pulliainen, E. (1965). Studies on the wolf (Canis lupus L.) in Finland. Annales Zoologici Fennici
2, 215-59.
Rabb, G. B., Woolpy, J. H., and Ginsberg, B. E. (1967). Social relationships in a group of captive
wolves. American Zoologist 7, 305-1 1.
Rausch, R. A. (1967). Some aspects of the population ecology of wolves, Alaska. American Zoologist
7, 253-65.

Reproduction in Captive and Wild Dingoes
Robertshaw, J. D., and Harden, R. H. (1985). The ecology of the dingo in north-eastern New South
Wales. 11. Diet. Australian Wildlife Research 12, 39-50.
Scott, J. P., and Fuller, J. L. (1965). 'Genetics and Social Behavior of the Dog.' (University of
Chicago Press: Chicago.)
Thomson, P. C. (1984). Use of buffer zones in dingo control. Journal of Agriculture of Western
Australia 25, 32-3.
Thomson, P. C. (1986). The effectiveness of aerial baiting for the control of dingoes in north-western
Australia. Australian Wildlife Research 13, 165-76.
Whitehouse, S. J. 0. (1977). The diet of the dingo in Western Australia. Australian Wildlife Research
4, 145-50.
Woolpy, J. H. (1978). The social organization of wolves. Natural History 77, 46-55.
Young, S. P. (1944). 'The Wolves of North America, Part 1.' (The American Wildlife Institute:
Washington, D.C.)
Zimen, E. (1975). Social dynamics of the wolf pack. In 'The Wild Canids: their Systematics,
Behavioral Ecology and Evolution'. (Ed. M. W. Fox.) pp. 336-62. (Van Nostrand Reinhold Co.:
New York.)
Manuscript received 21 October 1991; revised and accepted 6 February 1992