May 2008. After more than 10 years of captive breeding, scientists from Durrell Wildlife Conservation Trust will release three families of pygmy hogs - the world's smallest wild pig - in to wild grasslands in Assam, India, from the only captive population of the species in the world.
Thought extinct in the 1960s
John Fa, Director of Conservation Science for Durrell, says: "The pygmy hog was thought to be extinct in the 1960s as its habitat was disappearing due to human encroachment, livestock grazing and grass burning, but in 1971, the species was rediscovered in Assam. So, together with our partners, Durrell established the Pygmy Hog Conservation Programme in 1995 for recovery of the species.
"The programme aimed to study the causes of decline in the species and establish a sustainable captive population, which could be used to reintroduce animals back to their restored native habitat. The conservation breeding has been extremely successful and we are now ready to release them back in to the wild in May 2008 before the monsoon season begins."
The hogs will be released in the Gelgeli grasslands of Sonai Rupai Wildlife Sanctuary in Assam. Durrell, a charity that relies on donations to support its conservation programmes, has worked closely with the Sanctuary authorities to improve protection and control dry season burning of grasses. Sanctuary staff have also been trained in wildlife monitoring and habitat management.
A breeding facility was established at Basistha near the Assam capital, Dispur with the aim of raising a captive population ready for release back in to the wild. The programme is currently supported through a grant from the UK government's Darwin Initiative.
Captive breeding
Six wild hogs (two males and four females) were captured from Manas, Assam, in the Himalayan foothills in March 1996 and brought to the Basistha breeding facility. John Fa continues: "The breeding was a significant success and within five years the captive population rose to 77. A young wild hog rescued from a river in Manas was also added to the stock in 2001 and we currently have 79 pygmy hogs, which is the only captive population of the species in the world."
Pre-release site for acclimatisation
Three small family groups of hogs, containing 16 individuals in total, are currently in a pre-release site established at Potasali near Nameri National Park, Assam. This site contains large enclosures that replicate the hogs' natural grassland habitat. The animals have been kept here for the past four and a half months, which has allowed them to become used to the conditions they will face in the wild and reduces contact they have with humans. Up to release date, the hogs have shown naturalistic behaviour and an aversion to human contact which is a positive sign that they will fair well when released.
Durrell's local partner EcoSystems-India, along with other local non-governmental organisations, including Aaranyak, and the Centre for Environment Education, is working closely with local communities and stakeholders to improve awareness about the species and the management of tallgrass habitats.
The world's rarest wild hog
The pygmy hog, (Porcula salvania), is the world's rarest wild hog and most threatened by extinction. It stands about 25-30 cm from the ground and weighs up to 9 kg. The species was originally found in the narrow belt of alluvial tallgrass habitat that runs across the southern edge of the Himalayas in the Indian subcontinent. Tallgrass habitats, being very rich in nutrients, are highly suitable for cultivation and therefore came under significant pressures from expanding human populations, agriculture and uncontrolled harvesting; all of which caused the hog to die out. The continued practice of indiscriminate dry season burning and livestock grazing still threatens the last population in Manas.
Tall-grass critical habitat for several endangered species
The pygmy hog acts as an indicator for the state of the tall-grass habitat, which is crucial for the survival of a number of other endangered species such as the swamp deer (Cervus duvauceli), wild buffalo (Bubalus bubalis), hispid hare (Caprolagus hispidus) and Bengal florican (Houbaropsis bengalensis). The Pygmy Hog Conservation Programme acts as an umbrella for extensive work with both the habitats and their surrounding communities. It is hoped that through this project and the release of hogs, Durrell can support local communities to sustainably manage their natural resources and protect their biodiversity.
The Pygmy Hog Conservation Programme is a collaborative project between Durrell Wildlife Conservation Trust, IUCN/SSC Pigs Peccaries & Hippos Specialist Group, the Forest Department of Government of Assam and the Ministry of Environment & Forests, Government of India.

The pygmy hog, once thought extinct, is reintroduced to its native habitat in north eastern India