Part II: Species Accounts198
possible in open community forests with patches of clove trees
(Rode-Margono et al. 2016). The indifference of Bawean warty
pigs towards teak stands as a preferred habitat seems to set it
apart from Javan warty pigs on the mainland. Alternatively,
or additionally, the absence of European wild pigs may allow
Bawean warty pigs to access rather open habitats, while on the
mainland where they coexist with European wild pigs they
retreat more into the woodland (Olivier 1925, 1933). Finally, the
presence of wallows and deep litter are associated with higher
camera trapping rates and occupancy of Bawean warty pigs
(Rademaker et al. 2016).Movements and Home Range
There are no data about movement or home range of either
warty pig species. Population density is unknown for Javan
warty pigs and may be influenced by several factors such as
habitat suitability, hunting pressure, and presence or absence of
the potential competitor European wild pig. For Bawean warty
pigs, Rademaker et al. (2016) calculated a population density of
3–9 ind./per km^2. Population dynamics are currently unknown
for both species.Activity Patterns
Bawean warty pigs show a nocturnal activity pattern with peaks
in the early morning and late afternoon (Rademaker et al. 2016).
Feeding activities on grass- and bushland at forest edges and
forest plantations have been observed between 17:00 and 18:00
(no research conducted in the early morning; Rode-Margono
et al. 2016). Near agricultural areas where animals do raid crops,
activity may shift more into the night.Feeding Ecology
Not much is known about the feeding ecology of wild Javan and
Bawean warty pigs. Meijaard et al. (2011) referred to one account
from 1928 indicating that both the European wild pig and the
Javan warty pig feed on a range of animals and plant foods,
including fallen fruits, roots, worms, and insects. Farmers on
Bawean island name warty pigs as the fourth-most severe crop-
raider after rats, monkeys and insects, with most damage done torice, cassava, coconut, and banana plants (Rode-Margono et al. in
press). Camera trap videos from Bawean island (see Rademaker
et al. 2016) showed rooting soil and litter as the most common
feeding method. A single video showed an animal carrying a
large fruit, probably a jackfruit (Rademaker and Rode-Margono,
unpublished data). At Cikananga Conservation Breeding Centre
(CCBC), Sukabumi, West Java, Javan warty pigs are fed yam,
cassava, corn, cooked eggs, fish, chicken, bananas and banana
leaves, beans, papaya, elephant grass, and Zophobas morio as
enrichment.Reproduction and Growth
Gestation in Javan warty pigs is four months. Females make large
nests from leaf litter (Meijaard et al. 2011). Birth data from Javan
warty pigs at Surabaya Zoo, East Java, Indonesia, from 2003
to 2005 (n = 4; see Semiadi & Nugraha 2009) and CCBC from
2012 to 2015 (n = 14; extracted from Zoological information
Management System, ZIMS), both located on Java, show that
the litter size of Javan warty pigs is 1–5 (mean 3.6 ± 2.3, n = 18).
Reports from local hunters in West Java indicate that litter size
of Javan warty pigs is 50 per cent lower than European wild pigs.
Weaning in the wild is unknown, but at CCBC offspring is sepa-
rated from the mother at an age of 4–6 months. Animals prob-
ably reach sexually maturity at around 15 months; one female
that was born at CCBC gave birth at an age of about two years.
A birth profile from births at CCBC, where animals were
allowed to mate throughout the year, is shown in Figure 20.6.
It is interesting that within the same year births fell within a
narrow time period. In 2014 all four births at CCBC fell within
35 days (April to May); in 2015 five of six births fell within
52 days (August and September). The births in 2015 at CCBC
were shifted towards the end of the year probably due to con-
struction measures and a change from keeping animals in pairs
instead of large groups. If the sow has a miscarriage in the first
half of the year, she can conceive again (Bulk, personal obser-
vation). No systematic research has been conducted about
reproductive timing in the wild; however, most births seem to
occur in the rainy season from January to March, and females
with young are mostly seen between August and December
(Meijaard et al. 2011). In an unpublished year-long camera trap101Litter size
234567234567
Months8910 11 12Figure 20.6 Birth profile of 14 births
in Javan warty pigs (Sus verrucosus) at
Cikananga Conservation Breeding Centre,
Java, Indonesia, from 2012 to 2015..02212:41:37