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Part II: Species Accountsthe northern part of Orang are not affected adversely by floods
and were used for releases from 2011 to 2015.
Other suitable grassland habitats in the former range of the
species are being assessed to identify more release sites. In a
preliminary assessment of two potential sites in northern West
Bengal, the habitat in Jaldapara National Park was found to be
better than those in Gorumara National Park where the local
state government is keen to reintroduce pygmy hogs.Habitat Restoration
Sonai Rupai had been generally neglected and it was assumed
that reintroducing rare pygmy hogs may generate increased
interest for better protection of the PA. Project staff worked with
the Sanctuary authorities and staff to improve the protection
and management of the identified grasslands – largely to control
annual dry-season burning of grass and illegal livestock graz-
ing. Sanctuary staff were also trained in wildlife monitoring and
habitat management to help in the restoration of the grassland
habitat and the monitoring of hogs reintroduced there between
2008 and 2010.
Similar efforts were also initiated in Orang for better man-
agement of the grassland habitat before the release of pygmy
hogs started there in 2011. In addition to fire management,
PHCP staff advised and helped the Park authorities in erecting a
solar-powered fence along its northern boundaries.
In 2014–2015, the focus of restoration efforts shifted to
Barnadi, where the grassland patches had shrunk and were
overgrown with tree colonizers and weeds. PHCP staff worked
tirelessly along with gangs of labour to create open grasslands
where pygmy hogs were first reintroduced in 2016.Pre-release Protocol
A ‘pre-release’ facility was established at Potasali near Nameri
National Park in 2006 to prepare the captive-bred hogs for
release into wild. This facility includes four large (2400–3200 m^2
each) ‘pre-release’ enclosures with near-natural simulated habi-
tat. Social groups of unrelated and mostly young hogs are inte-
grated at the breeding centres before being brought here usually
around the end of December every year. Each social group is
maintained for 5–6 months in a separate semi-wild enclosure
under minimal human contact. Their supplementary diet is
gradually reduced to less than a quarter of their daily require-
ment to encourage natural foraging. Besides encouraging natu-
ral behaviours like nest-building, these measures help mitigate
tameness and other behavioural characteristics acquired in cap-
tivity. Observations on their behaviour and habitat use from a
hide revealed that these hogs start behaving like wild animals
after spending about 2–3 months in the ‘pre-release’ enclosures.Release Protocol
Once the habitat at the selected reintroduction site appears suit-
able for the release of hogs, i.e. the grass and vegetative cover
looks reasonably dense and the soil is softened after a few pre-
monsoon showers for easier rooting by newly released hogs,
final preparations are made for releasing the hogs. At the three
reintroduction sites in Assam this has happened around the
third week of May between 2008 and 2016.Each social group is released at different secluded but easily
accessible locations in the release site. A temporary ‘soft-release’
enclosure, about 100 m^2 in size, is erected using woven bamboo
panels and bamboo poles. A platform hide is constructed on a
tree about 30–50 m away and the enclosure and the hide tree
is rigged with a two-line solar-powered fence as a precaution
against wild elephants and other large animals.
The hogs in the ‘pre-release’ enclosure are rounded up, exam-
ined, marked, given shots of anti-parasitic and a sedative, and
are transported in individual crates to the release site. Some are
also fitted with a radio transmitter for post-release monitoring.
On arrival at the reintroduction site the crates are simply placed
in the ‘soft-release’ enclosure and the hogs are allowed to emerge
on their own. The animals are maintained in the ‘soft-release’
enclosures for three days under continuous surveillance and are
offered a full complement of diet during this period. After three
days, the hogs are finally released by simply removing one or two
sections of fence and allowing them to find their own way out.
Once all the hogs are gone the fence is dismantled and a camera
trap is placed at a spot that is visible from the tree hide to use the
locations as a baiting site. The quantity of supplementary diet is
gradually reduced every day to encourage them to find natural
food, and after a week only a few pieces of delicacies (e.g. sweet
potato, dates) are offered twice a day at the baiting site to moni-
tor them.Post-release Monitoring Methods
Pygmy hogs are extremely shy and secretive in the wild.
Monitoring them is a challenge as they remain hidden in tall,
dense grass and rarely emerge into the open. Although camera-
trapping at the baiting site provides some information about
their continued survival and body conditions, they usually stop
visiting the baiting site after a month or two. A few of them move
away soon after release and rarely, if ever, visit the baiting site.
Other methods include the screening of field signs such as nests,
faeces, footprints, and foraging marks, but even these do not
provide adequate information about the behaviour and move-
ment of the animals. The dense grass in good pygmy hog habitat
often reaches above 3 m and these grasslands also shelter large
and dangerous animals such as rhinoceros, elephants, tiger,
gaur, and buffalo.
Radio telemetry can be a useful method to monitor them,
but attaching radio transmitters to the pygmy hogs has remained
an annoying problem largely due to the animal’s morphological
and behavioural traits. Different attachment methods such as a
harness with backpack, implants, and ear tags have been tried
without much success (Narayan & Deka 2015). Owing to the
streamlined, tapered profile of the pygmy hog’s head it was nec-
essary to design a harness, rather than a simple collar, to carry
the radio transmitter and battery. A harness designed and used
by Oliver (1980) was modified and deployed again in 1996 and
2008 by PHCP. However, the experiment was discontinued as
the harness impacted the hogs’ locomotion and the unsuitable
material of the belt caused injuries. Later, implants were tried on
seven individual hogs in 2011 and 2012 during releases in Orang
and these were inserted extraperitoneally behind the abdominal
muscles as the facilities at the pre-release centre were inadequate.02412:46:11