Ecology, Conservation and Management of Wild Pigs and Peccaries

Part II: Species Accounts

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discolours the hind-end of the oestrous female. The male follows

the oestrous female, sniffs her urine while ‘chanting’, and exhib-

its ‘courtship gait’. The male rests his chin on her rump until she

responds by standing still and allowing mounting. Mounts typi-

cally last about 3 minutes but can be <1 minute. After coitus a

vaginal plug forms, presumably to prevent insemination from

other males. Gestation is variably reported, but is in the range

of 150–180 days (Child et al. 1968; Cumming 1975; Boshe 1981;

Mason 1982; Somers et al. 1995).

Phacochoerus africanus has distinct annual mating and

birth seasons where there is one wet season (November–

April): it mates at the end of the wet season with births near the

start and early part of the wet season. As such, over southern

Africa, mating occurs March–May and birth occurs October–

December (Shortridge 1934; Child et al. 1968; Cumming

1975). In south-east Tanzania, where there is also one wet sea-

son (December–April), mating occurs March–April and birth

occurs September–October (Geigy 1955; Boshe 1981; Rodgers

1984). In south-central Ethiopia, where the one wet season

is March–October, mating occurs November–December

and birth occurs April–May (Deribe et al. 2008). In south

Kenya, nearer the equator, where there are two wet seasons

(November–December; March–June) and mean annual rainfall

is 90–140 cm, the mating and birth seasons are similar to those

to the south: mating April–May and birth October–November

(Frädrich 1965; Ogutu et al. 2014). In contrast, farther north, on

the equator, in Kenya’s Lolldaiga Hills, where the timing of the

two wet seasons is similar to that in south Kenya but rainfall is

lower (mean 70 cm/year), mating occurs in November–January

and birth occurs in April–June (T. Butynski & Y. de Jong, per-

sonal observation). To the west, where the mean annual rainfall

is often (but not everywhere) higher, the wet seasons are less well

defined, and dry periods less severe (e.g. south-west Uganda and

east Democratic Republic of Congo), there is one prolonged

(>4 months) birth season, two birth seasons, or birth occurs

during all months (Bigourdan 1948; Geigy 1955; Child et al.

1968; Clough 1969; Plesner Jensen et al. 1999). See table 4 at

http://www.wildsolutions.nl/phacochoerus/.

In south Kenya, fewer females conceive when rainfall during

the prior 6–10 months is < 30 cm. There is a positive relation

between annual rainfall and offspring survival (Mason 1990;

Ogutu et al. 2015).

For a large mammal, P. a f r i c a n u s has a high reproductive

rate. Both sexes are able to reproduce throughout their lives, or

nearly so. From 63 per cent to 100 per cent of adult females breed

each year, with 75–95 per cent typical. Mean foetal (= prenatal)

litter size ranges from 2.6 to 4.0. The largest litter reported is

eight. Mean litter size within a few weeks of emerging from bur-

row ranges 2.0–3.3. Sex ratio at birth is at parity. Birth weight

is 480–850 g (Bigourdan 1948; Geigy 1955; Child et al. 1968;

Smithers 1971; Cumming 1975; Boshe 1981; Mason 1982, 1986,

1990; Rodgers 1984; Somers & Penzhorn 1992).

The female leaves the sounder about 3 weeks before partu-

rition and gives birth alone in a burrow. Piglets are uniformly

pinkish at birth (no spots or stripes) with a denser coat than

the adult. They huddle in the chamber at the end of the burrow.

Sometimes they are moved to another burrow when <2 weeks

of age, but they typically first emerge from the burrow at 10–14

days of age. During weeks 2–7, piglets increasingly accompany

the mother outside the burrow and begin grazing at about

2 weeks. They are with the mother outside the burrow through-

out the day by about 7 weeks. Weaning starts at about 2 months

and is complete at about 3–4 months. The weaning mother

walks or sits when the young want to suckle. The male has no

input into raising the offspring (Frädrich 1965; Child et al. 1968;

Cumming 1975, 2013; Mason 1982; White & Cameron 2009).

Suids are unique among ungulates in that some species, includ-

ing P. a f r i c a n u s, are facultative cooperative breeders; adoption,

allomothering, and allosuckling occur (Child et al. 1968; Radke

1991; Somers et al. 1995; Plesner Jensen et al. 1999).

Growth is influenced by season, being fastest during the wet

season when the food availability is highest. Adult size is reached

Table 9.2 Species of grass most eaten by common warthog Phacochoerus africanus at nine sites.

Site Species of grass most eaten Source

Queen Elizabeth National Park, south-west Uganda Sporobolus homblei, Microchloa kunthii, Brachiaria sp., Cynodon dactylon,

Chrysochloa orientalis

Field 1970

Nairobi National Park, central south Kenya Sporobolus pellucida, Eragrostis tenuifolia, Harpachne schimperi, Cynodon

dactylon, Digitaria macroblephara

Frädrich 1965

Tarangire National Park, north-east Tanzania Cynodon dactylon, Cenchrus ciliaris, Eragrostis superba, Sporobolus marginatus Lamprey 1963

Mkwaja Ranch, Saadani National Park, north-east

Tanzania

Cynodon dactylon, Eragrostis superba Treydte et al. 2006

Selous Game Reserve, south-east Tanzania Urochloa trichopus, Echinochloa haplocada, Cynodon dactylon Rodgers 1984

North Botswana Cynodon dactylon, Imperata cylindrica, Echinochloa spp. Smithers 1971

Sengwa Wildlife Research Area, north-west

Zimbabwe

Sporobolus marginatus, Chloris virgata, Sporobolus festivus, Urochloa pullulans,

Digitaria milanjiana, Tristachya superba

Cumming 1975

KwaZulu-Natal, central east South Africa Urochloa mosambicensis, Panicum maximum, Panicum coloratum, Chloris virgata,

Digitaria argyrograpta, Sporobolus nitens, Sporobolus smutsii, Cynodon dactylon,

Dactyloctenium austral

Mason 1982

Kruger National Park, north-east South Africa Cynodon dactylon, Echinochloa holubii, Echinochloa stagnina, Ischaemum afrum Mason 1990

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