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Pigs, Peccaries and Hippos
Status Survey and Action Plan (1993) Chapter 2.2 The Collared Peccary (Tayassu tajacu) Richard E. Bodmer and Lyle K. Sowls Status and Action Plan Summary Status category 1-2 (widespread and locally abundant
or relatively secure). The collared peccary is the most abundant, most
widely distributed and least threatened of the three extant species. It
occurs in a variety of habitats, including woodlands, tropical dry and rain
forests, savannas, chaco and deserts, from the southern U.S.A. through to
northern Argentina. Owing to its large geographical range, evident
adaptability, relatively high reproductive rate and proportionally high
population densities, it does not merit high conservation priority at the
present time. Nonetheless, these peccaries are still hunted extensively for
their meat and hides, and much of their natural habitat is being destroyed.
As a result, the species has already been extirpated in parts of its former
range and it is locally threatened in other areas. Given the continuing rates of habitat destruction
and potential for over-hunting of this species, the status of all populations
requires monitoring. This and related recommendations, including the species'
continued inclusion on Appendix II of CITES, are outlined in the Action Plans
for these animals, though those recommendations relating to the management of
hunted populations, control of pelt and meat markets and other aspects
relating to human exploitation are detailed elsewhere (see Bodmer et al., 1993). The most important
non-human oriented priorities for applied research and possible future
conservation action for this species are the continued collection of regional
data on population distribution and status, and a thorough review of its
subspecific taxonomy. This review, which should be undertaken at the genetic
as well as gross morphological level, should enable a better understanding of
the genetic diversity of this species and facilitate the identification of
future conservation priorities at the population and subspecies level.
Further longer-term studies of the species' ecology and social behaviour in
habitats other than the south-western U.S.A. are also of importance. Introduction The collared peccary, Tayassu tajacu, is the smallest, most abundant and most widely
distributed of the three extant species of peccaries. It occurs in a wide
range of habitat types from tropical rain forest to semi desert, from the
southern U.S.A. in the north to northern Argentina in the south; one of the
widest distributions of any American terrestrial mammal. The collared peccary is the smallest of the living
Dicotylidae. Total body weights of adults usually range from 15-28 kg; males
generally being larger than females (Sowls, 1984). The species is
characterized by its relatively large head, fine and slender legs, a dark
brown pelt with white-tipped hairs, and a white collar circumscribing the
neck that extends obliquely upward and backwards from the jaw. For a full
description see Grubb & Groves (1993). Variation in size and pelage color
has lead to various subspecies categorizations, the latest recognizing ten
separate subspecies of T. tajacu
(Hall, 1981). However, as Grubb and Groves (1993) have stated, this is almost
certainly too many and the subspecific taxonomy of T. tajacu requires revision if a proper understanding of its
genetic and geographic variation is to be attained. For this reason, we
follow the latter authors' informal recognition of three 'subspecies' groups'
(Fig. 1). Sowls (1984) and Emmons (1990) also noted that savannah and desert
populations in xeric habitats in the northern parts of their range tend to be
lighter gray and heavier than those in similar habitats in the south, whereas
tropical forest forms are darker and larger than animals inhabiting open
environments. Distribution The collared peccary occurs in Arizona, New Mexico
and Texas in the U.S.A., a large part of Mexico and Central America, the
entire Amazon basin, the Pacific coastal forest of Colombia, Ecuador and
Peru, the llanos and the forest of Venezuela, the Guianas and Suriname, the
Pantanal and Mato Grosso of Brazil and the Chaco of Paraguay, Bolivia and
northern Argentina (Fig. 1). The upper limit of its range along the Andean
foothills is between 1,000-1,500 m (Grimwood, 1969). Some of the larger
islands near the mainland in the Caribbean, such as Cozumel and Trinidad and
Tobago, also have populations of T. tajacu. However, islands further away
from the mainland do not have peccaries except where they have been
introduced, such as in Cuba (Varona, 1973; see later text). |
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Link to Fig. 1:
Approximate known range of the collared peccary, Tayassu tajacu ssp. Habitat, Ecology and Behavior T. tajacu is not only the most widely
distributed of the three peccary species, it is also by far the most
adaptable. It inhabits tropical forests where average midday temperatures are
around 27oC, relative humidity is high (c. 80%), and annual rainfall often
exceeds 2,000 mm per year. At the other extreme, the species is also found in
desert areas where midday temperatures reach 45oC, relative humidity is below
6%, and annual rainfall is less than 250 mm. At the northern fringe of its
range collared peccary maintain viable populations in areas where the winter
night temperature falls below 0oC and light coverings of snow are
occasionally present. The species' evident tolerance of low seasonal
temperatures is exceptional for an animal also living in the tropics. The species' diet varies in accordance with this
range of habitats. Foods of T. tajacu
can generally be classified as roots, tubers, fruits, nuts and edible parts
of green growing plants. In tropical forests, diets are dominated by palm
fruits and supplemented with invertebrate animal material (Kiltie, 1981b;
Bodmer, 1989), whereas in deserts environments their diet is dominated by the
cladophylls of prickly pear cactus (Opuntia
spp.) (Corn and Warren, 1985). Densities of collared peccary differ between habitats
and rainfall patterns. In the south-eastern U.S.A. densities range from 10.9
ind./km2 in the Tucson mountains (Schweinsburg, 1969), 7.3 ind./km2 at the
King Ranch, Texas (rainfall: 660 mm/year) and 3.5 ind./km2 at the Welder
Wildlife Refuge, Texas (rainfall: 762 mm/year), to only 1.1 ind./km2 in a
Texas desert with 279 mm of rainfall/year (Low, 1970). In the llanos of
Venezuela collared peccary density is 8 ind./km2, whereas, in gallery forests
in Venezuela it is 2 ind./km2 (Eisenberg, 1980) and in the Pantanal of Brazil
it is less than 1 ind./km2 (Schaller, 1983). Densities of T. tajacu in
tropical forest range from 9 ind./km2 on Barro Colorado Island, Panama
(Glanz, 1982), to 5 ind./km2 in Manu National Park, Peru (Terborgh et al.,
1986). Collared peccary densities decrease in hunted areas
(Emmons, 1984), but are less susceptible to human hunting pressure than cebid
primates and other large-bodied mammals (Bodmer et al., 1990). Like all peccaries, T. tajacu is a highly
social animal, living in herds, which vary from fewer than six to over 30
individuals. Home ranges of groups average approximately 150 ha, but can
range from 24 to 800 ha (Sowls 1984). Social herds are kept together by
vocalizations and a strong musk released from the dorsal gland, scent from
the latter being deposited on tree trunks, rocks and other individuals (Byers
1980). The collared peccary has a diurnal/crepuscular
activity pattern, feeding in early hours of the night. They commonly rest in
small groups of three to four individuals and often seek shelter in burrows,
caves and under logs. Collared peccaries frequently wallow in mud or dust and
rarely spend time auto-grooming (Sowls 1984). Births have been recorded at all times of the year,
though in the southern U. S. A. there is a birth peak during the summer rainy
season. The gestation period is 142 to 145 days and the usual litter size is
two. The young are highly precocial at birth, following their mothers within
an hour of parturition and stopping to suckle at frequent intervals. In one
case infants were observed to spend up to 24% of their time suckling (Sowls
1966). Weaning occurs at approximately 6 weeks (Sowls 1984). Threats To Survival The two major threats to the survival of collared
peccary are over-hunting and excessive destruction of its natural habitats.
These factors have already resulted in the extensive fragmentation of peccary
populations and its extirpation over large parts of its former range. Where
these processes have been most severe, these and other larger-bodied animals
have also disappeared from many of the smaller/least-protected reserves (e.g.
in most of the smaller reserves in the Atlantic Forest region of
south-eastern Brazil; W. Oliver, pers. comm.) and they are already extinct in
two countries, Uruguay (Mones and Ximenez, 1980) and El Salvador (R.
Mittermeier, pers. comm.) Indigenous tribes in the Americas have hunted
collared peccary for countless generations as an important source of animal
protein and have maintained a sustained balance between human needs and
peccary populations. Indeed, Indians have altered forests for agriculture in
a manner that often increases peccary densities (Steward, 1946, 1948), and in
parts of Mexico and Central America these animals are reported to cause
considerable damage to subsistence crops. However, where modern market forces
and updated hunting and agricultural techniques have been introduced and
human population expansion has been uncontrolled or encouraged, ecological
balances are undermined and animal populations have become threatened. These broad socio-economic circumstances are by no
means specific to peccaries, but threaten whole ecosystems and their
dependent animal and plant species. The more specific threats to T. tajacu are the hide and meat trade
which are detailed in the section on 'Economic Importance and Human
Utilization of the Peccaries' (see later text). Conservation Measures Taken Collared peccaries occur in a large number of national
parks and other reserves throughout their extensive range in the Americas. In
many of these areas populations are relatively secure, although poaching and
inefficient protection are common and may nullify the nominal protection
afforded by the designation of protected sites. Conservation measures specific to collared peccaries
include national wildlife protection legislatures, which vary from country to
country, and the recent (1986) inclusion of this and other peccary species on
the Appendices of CITES; the latter to enhance regulation of the
international trade in hides of these animals. Specific management
regulations appertaining to hunting and movement of peccary products exist
for all countries within the geographical range of T. tajacu. In the U.S.A., for example, the species is managed as
a game animal outside national parks and reserves, and may be hunted with
permits under a quota system operated by the state authorities. In Brazil
there is a total ban on all hunting of peccaries by non-indigenous people,
though this is largely unenforced in many states. Subsistence hunting is
permitted in Colombia and Venezuela, but these countries prohibit the
movement of peccary products, whilst in other countries, such as Peru,
subsistence hunters are allowed to trade peccary products under management
laws. However, in these and many Central and South American countries, rural
people are often unaware of wildlife management regulations or these are
flouted, sometimes quite openly, owing to the common lack of resources and
trained personnel for the enforcement of protective legislation. The collared peccary was originally placed on
Appendix III of CITES and in 1986 it was moved to Appendix II. Animals listed
on Appendix II can be legally traded across international borders, but
monitoring of this trade between signatory nations is greatly enhanced.
Details concerning the current levels of trade in the hides of this species,
and other conservation - related issues appertaining to it, are discussed in
Section 2.5. |
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Table 2 Differences in collared peccary density with habitat and rainfall
pattern Geographcal
Area Density Habitat Rainfall Reference (ind./km2)
(mm/year) Tuscon Mountains 10.9 Sonoran
desert Shweinsburg
1969 King Ranch, Texas 7.3 Chapparal
660 Low 1970 Welder Wildlife Refuge, 3.5 and
deciduous 726 Low
1970 Texas woodland Texas desert 1.1 desert 279 Low
1970 Llanos, Venezuela 8.0 Llanos Eisenberg
1980 Gallery forest, 2.0 Gallery
forest Eisenberg
1980 Venezuela Pantanal, Brazil <1.0 Pantanal Schaller
1983 Barro Colorado I., 9.0 Tropical
forest Glanz
1982 Panama Manu N.P., Peru 5.0 Tropical
forest Terborgh
et al. 1986 |
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Conservation Measures Proposed: An Action Plan Since this species is not considered to be seriously
threatened over most of its still extensive range at present, such actions as
are required in the short term are essentially directed towards an improved
understanding of its regional genetic diversity, and its distribution,
population biology and status in areas and habitats, which have not yet been
studied. The continued monitoring of known threats to the peccary populations
in some countries, particularly habitat destruction and hunting pressure are
also identified as priorities for this and other peccary species, but these
and other factors relating to human over-exploitation are detailed and
summarized elsewhere (see sections 2.5 and 2.6 of this Plan). Given these
provisos, the objectives and priorities for research and conservation action
for the collared peccary may be described as follows: Objectives 1. To promote a
better understanding of distribution, current population status, and the
nature and levels of human utilisation and other potential threats to this
species in all countries in which it occurs. 2. To encourage
a thorough reappraisal of its systematics in order to identify and implement
management strategies directed towards the most threatened forms. 3. To promote further
research on this species, particularly field studies and surveys in habitats
and areas which have not yet been investigated, on topics relevant to its
continued management on a sustainable basis and the enhanced protection of
potentially threatened forms. Priority Projects 1. Collect data on the distribution and population status of this and
other peccary species in all South and Central American countries. A survey, incorporating
questions about the species' legal status, its occurrence in protected areas,
levels of utilisation and its potential socio-economic importance, etc., has
already been initiated by the PPSG, but is not yet complete and additional
data is required for most countries. 2. Thoroughly reassess the
subspecific taxonomy of the species. This should include a
genetic analysis of variability within and between populations as well as
gross morphological features, osteological characters and pelage form/color.
Such a review will facilitate identification of any potentially threatened
nominate forms so that appropriate conservation measures can be initiated to
ensure their survival. The systematic relationships of this species with T. pecari, also needs to be resolved
(see Grubb and Groves 1993). 3. Study the behaviour and
ecology of collared peccaries in tropical and sub-tropical habitats. This information can be
compared to the extensive data already available from the south-western
U.S.A. Such comparative data on the ecology and population dynamics of major
herbivores are not only of considerable scientific interest, but are also
crucial to the determination of appropriate management strategies. Specific
behavioral questions, which also require further study, include the 'incest
taboos’, which are also of great scientific interest and are potentially
important to the successful management of small isolated populations, either
in the wild or captivity. 4. Establishment a
properly structured captive breeding program. Although this species is
relatively well represented in captivity at present, the overwhelming
majority of captive animals are of unknown or mixed origin. Very few
collections have made any attempt to ascertain, let alone ensure, the genetic
integrity of recognized subspecies and regional populations. This is hardly
surprising given the present confused state of the species' subspecific
taxonomy, and the highly restrictive regulations appertaining to the movement
of these animals across international borders; but every attempt should be
made to rationalize existing interests and resources devoted to the captive
management of these animals, which serve little useful conservation purpose
at the present time. References Bodmer, R. E.
1989. Ungulate biomass in relation to feeding strategy within Amazonian forest.
Oecologia 81: 547-500. Bodmer, R. E.,
Fang, T. G. and Moya I, L. 1990. Primates and ungulates: a comparison in
susceptibility to hunting. Primate Conservation, 9: 79-83. Byers, J. A.
1980. Social behaviour and its development in the collared peccary. (Unpubl.)
Ph.D. thesis, Univ. of Colorado, Boulder: 185 pp. Corn, J. L. and
Warren, R. J. 1985. Seasonal food habits of the collared peccary in south
Taxas. J. Mamm. 66: 155-159. Eisenberg, J.
F. 1980. The density and biomass of tropical mammals. In: M. Soule and B. A.
Wilcox (eds.): Conservation Biology, Sinauer Associates, Sunderland,
Massachusetts: 35-56. Emmons, L. H.
1984. Geographic variation in densities and diversities of non-flying mammals
in Amazonia. Biotropica 16: 210-222. Emmons, L. H.
1990. Neotropical Rainforest Mammals: A Field Guide. University of Chicago
Press, Chicago. Glanz, W. E.
1982. The terrestrial mammal fauna of Barro Colorado Island: censuses and
long-term changes. In: E. G. Leigh, A. S. Rand and D. M. Windsor (eds.): The
Ecology of a Tropical Forest: Seasonal Rhythms and Long-terms Changes.
Smithsonian Institution Press, Washington, D. C.: 455-468. Grimwood, I. R.
1969. Notes on the distribution and status of some Peruvian mammals, 1968.
American Committee for International Wild Life Protection and New York
Zoological Society, Special Publication No. 21: 1-87. Hall, E. R.
1981. The Mammals of North America; 2nd Edition, Vol. 2. John Wiley and Sons,
New York. Kiltie, R. A.
1981a. The significance of interlocking canines in rain forest peccaries
(Tayassuidae). J. Mamm. 62: 459-469. Kiltie, R. A.
1981b. Stomach contents of rain forest peccaries (Tayassu tajacu and T.
pecari). Biotropica 13 (3): 234-236. Low, W. A. 1970.
The influence of aridity on reproduction of collared peccary (Dicotyles tajacu Linn.) in Texas.
(Unpubl.) Ph.D. Thesis, University of British Columbia, Vancouver. Mones, A. and
Ximenez, A. 1980. Hallazgo de los mamiferos extincos del Uruguay. Rev. Fac.
Humanidades y Ciencia, Serie Ciencias Biologicas, 1 (12): 203-207. Schaller, G. B.
1983. Mammals and their biomass on a Brazilian ranch. Arquivos de Zoologia
31: 1-36. Schweinsburg,
R. E. 1969. Social behaviour of the collared peccary (Pecari tajacu) in the Tucson Mountains. (Unpubl.) Ph.D. Thesis,
University of Arizona, Tucson. Sowls, L. K.
1966. Reproduction in the collared peccary (Tayassu tajacu). In: I. W. Rowlands (ed.): Comparative Biology of
Reproduction in Mammals. Zoological Society of London, London: 155-172. Sowls, L. K.
1984. The Peccaries. The University of Arizona Press, Tuscon, Arizona. Steward, J. H.
1946. The Marginal Tribes. Handbook of South American Indians, Vol. 1.
Smithsonian Institution Bureau of American Ethnology. Steward, J. H.
1948. The Tropical Forest Tribes. Handbook of South American Indians, Vol. 3.
Smithsonian Institution Bureau of American Ethnology. Terborgh, J.,
Emmons, L. H. and Freese, C.1986. La fauna silvestre de la Amazonia: el
despilfarro de un recurso renovable. Boletin de Lima 46: 77-85. Varona, L. S. 1973.
Catalogo de los Mamiferos Vivientes y Extinguidos de las Antillas. Academia
de Ciencias de Cuba, Havana. |
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Next: Chapter 2.3 – The
White-lipped Peccary |