Status Survey and Conservation Action Plan - IUCN

populations, but this number decreases by Robertsonian
translocations over the species’ extensive range such that
the continental European populations have only 36 chromosomes
(Bosma et al. 1984). Eurasian wild pigs are also
markedly variable in size, pelage and some other characters,
and an enormous number of subspecies, and several
different species, have been described. However, in a
major review of the genus Sus, Groves (198 1) argued that
many of these named forms were synonymous or, in some
cases were actually naturalized feral or hybrid (with S.
celebensis) populations. Groves accordingly recognized
only 16 subspecies, including a previously undescribed
form, S. s. davidi, from Pakistan and northwestern India,
though he also drew attention to a small, as yet unclassifiable,
skull from Central Province, Sri Lanka, which may
represent another new subspecies. Only a few of the currently
recognized subspecies, such as the insular taivanus
(Taiwan) and riukiuanus (Ryukyu Is., south Japan), have
clearly defined ranges, and precise data is lacking on the
range limits/intergradation zones of many of the continental
forms. Groves and Grubb (this vol., section 5.1) have
therefore distinguished four “subspecies groupings”, based
on both geographic and morphological criteria, as follows:
1. “Western races” of Europe (scrofa and meridionalis),
North Africa (algira) and the Middle East (Zybicus),
extending at least as far east as Soviet Central Asia
(attila and nigripes).
2. “Indian races” of the Sub-Himalayan region from Iran
in the west (davidi) to north India and adjacent countries
as far east as Burma and west Thailand (cristatus),
and south India and Sri Lanka (afinis and subsp. nov.).
3. “Eastern races” of Mongolia and the Soviet Far East
(sibiricus and ussuricus, Japan (leucomystax and riukiuanus),
Taiwan (taivanus), to southeast China and
Vietnam (moupinensis).
4. “Indonesian race” (or banded pig) from the Malay
Peninsula, Sumatra, Java, Bali and certain offshore
islands (vittatus).
Former
and Present Distribution
S. scrofa is one of the most widely distributed terrestrial
mammals, and has by far the largest range of all suiformes.
It occurs throughout the steppe and broadleaved forest
regions of the Palaearctic, from western Europe to the
Soviet Far East, extending southward as far North Africa,
the Mediterranean Basin and the Middle East, through
India, Indo-China, Japan (including the Ryukyu Chain),
Taiwan and the Greater Sunda Islands of southeast Asia.
Populations east of Bali are probably all introduced. It
has been extinct in the British Isles since sometime in the
17th century, despite attempted introductions of new stock
from Europe (Harting 1880). It is also extinct in southern
Scandinavia, over extensive portions of its recent range in
west-central and eastern parts of the (former) Soviet Union
(Heptner et al. 1961), and in northern Japan (Chiba 1964,
1975). The species was last reported in Libya in the 1880s
and it became extinct in Egypt in about 1902 (Hufnagl
1972; Fig. 10).
Habitat, Ecology, and Behavior
The Eurasian wild pig occupies a wide variety of habitats,
from semi-desert to tropical rainforests, temperate woodlands,
grasslands and reed jungles; often venturing onto
agricultural land to forage. The species is omnivorous,
though stomach and fecal contents analysis indicate that
vegetable matter, principally fruits, seeds, roots and tubers,
constitutes about 90% of the diet (Spitz 1986). A field
study of the Indonesian wild pig, S. s. vittatus, in Ujung
Kulon National Park in Java, indicated that these animals
are predominately frugivorous, feeding on about 50
species of fruits, especially those of strangling figs (Ficus
spp.), and that they are important seed dispersal agents
(Pauwels 1980). By comparison, analysis of the stomach
contents of wild pigs (also S. s. vittatus) in agricultural
areas of West Malaysia by Diong (1973), revealed that
sugar cane, tapioca and rice were the commonest food
items, but that usually more than one type of food had been
,eaten, even where a single cultivated crop was abundant.
Other items commonly consumed by these pigs included
soil, earthworms, roots and other vegetable matter and, in
mangrove areas, molluscs, crabs and other arthropods and
even fishes. The consumption of invertebrate and small
vertebrate prey may be a necessary component of the diet,
since a study of free-ranging domestic pigs in Papua New
Guinea revealed that animals fed ad Zibitum lost weight
when denied earthworms (Rose and Williams 1983). In
common with its feral derivatives (Oliver and Brisbin, this
vol.), S. scrofa has also occasionally been reported to predate
upon larger vertebrates, such as deer fawns and (tethered)
goats (Hoogerwerf 1970), though it is possible that
such incidents involve only a few individuals in the population;
this aspect was also noted by Pauwels (1980) when
referring to the predation of sea turtle nests by wild pigs
in Ujung Kulon. Similarly, a large boar (S. s. cristatus)
in Royal Chitawan National Park, Nepal, which was seen
to displace an adult leopard from its kill (a domestic buffalo
calf), which it then partly consumed (W. Oliver, pers.
obs.), was reported by Park staff to regularly commandeer
such kills but that no other individual pigs had been seen to
do this.
113