In Situ and Ex Situ Conservation

There are two basic ways to save a plant or animal species from dying out. In situ conservation means protecting the species in its natural home, for example by protecting a forest or grassland so that the animals living there are safe. Ex situ conservation means protecting the species outside its natural home, for example in a zoo, a breeding centre, a botanical garden or a seed bank. In situ is Latin for "in place"; ex situ means "out of place".

You can think of it like protecting a family's heritage. In situ is like repairing and guarding the old family house so the family can keep living there. Ex situ is like keeping copies of the family's important papers in a bank locker in another city, just in case the house is damaged.

Why do we need both?

The best way to save a species is to save its habitat, because a species is part of a web of food, shelter and other species. So in situ is always the first choice. But sometimes a species becomes so rare that one disease, one drought or one bad breeding season could wipe it out in the wild.

Then scientists keep a back-up population in safe captivity. Ex situ work buys time and acts as an "insurance policy" while the threats in the wild are reduced.

Where does the idea come from (international law)?

The key global treaty is the Convention on Biological Diversity (CBD), adopted at the Earth Summit in Rio de Janeiro in 1992. India is a party to it.

• The CBD defines in situ conservation as protecting ecosystems and natural habitats and keeping viable populations of species in their natural surroundings. For domesticated or cultivated species, it means the surroundings where they developed their special features (for example, a traditional crop variety on a farmer's field).
• It defines ex situ conservation as conserving parts of biodiversity outside their natural habitats.
• Article 8 of the CBD lists in situ measures, such as setting up protected areas.
• Article 9 lists ex situ measures, and says they should be used mainly to complement (support) in situ measures, not to replace them.

India gave effect to the CBD through the Biological Diversity Act, 2002.

How does in situ conservation work in India?

India protects habitats through a network of protected areas under the Wildlife (Protection) Act, 1972. As of February 2025, India had 1,134 protected areas covering about 5.69% of its land:

• 106 National Parks
• 574 Wildlife Sanctuaries
• 145 Conservation Reserves
• 309 Community Reserves

Other in situ tools include Biosphere Reserves (large areas that combine strict protection in a core zone with human use in outer zones), Tiger Reserves under Project Tiger (1973), Elephant Reserves under Project Elephant (1992), and sacred groves, which are patches of forest protected by local communities for religious reasons.

How does ex situ conservation work?

There are several methods, used for different kinds of life.

• Zoos and conservation breeding centres: Animals are kept and bred in controlled conditions. In India, zoos are regulated by the Central Zoo Authority (CZA), set up in 1992 under Chapter IVA (Sections 38A to 38J) of the Wildlife (Protection) Act, 1972. Under Section 38C, the CZA identifies endangered species for captive breeding and assigns this job to particular zoos.
• Botanical gardens and arboreta: Living collections of plants and trees.
• Seed banks and gene banks: Seeds are dried and stored at very low temperatures so they stay alive for decades. India's national gene bank is run by the ICAR-National Bureau of Plant Genetic Resources (NBPGR), New Delhi.
• Cryopreservation: Seeds, pollen, tissues, sperm or embryos are stored in liquid nitrogen at about minus 196°C, where almost all life processes stop. NBPGR started India's national cryobank facility in 1987.
• Tissue culture (in vitro conservation): Small pieces of plant tissue are grown in glass containers in a lab.
• Global back-ups: The Svalbard Global Seed Vault in Norway, opened in 2008, stores duplicate seed samples from gene banks across the world. India made its first deposit (pigeon pea samples from ICAR) in 2014.

From captivity back to the wild

Ex situ conservation is not meant to keep animals in cages forever. The final aim is usually reintroduction: releasing captive-bred animals into the wild. This is done step by step.

• First, a captive population is built up so it is large and genetically healthy.
• Next, young birds or animals are trained for wild life: finding food, recognising predators and moving in large areas.
• They are often first kept in a fenced enclosure inside their natural habitat. This is called a soft release. (Letting them go directly is a hard release.)
• Finally, they are released and tracked with radio or satellite tags to see if they survive and breed.

India's examples of ex situ success

• Crocodiles and gharial: India started a crocodile conservation project in 1975. Between 1975 and 1982, it set up 16 breeding and release centres, and gharials were released into rivers such as the Chambal.
• Vultures: Vulture numbers crashed in the 1990s, mainly because of the veterinary drug diclofenac. The first Vulture Conservation Breeding Centre was set up at Pinjore, Haryana in 2001 by the Bombay Natural History Society (BNHS) with the Haryana Forest Department.
• Pygmy hog: A captive breeding project started in 1995 at Basistha near Guwahati, Assam, and captive-bred hogs have been released into the wild.
• Great Indian Bustard: Breeding centres at Sam (2019) and Ramdevra (2022) in Rajasthan; the first captive-bred birds were released in 2026.

Commonly confused concepts

• In situ vs ex situ: In situ protects species where they naturally live (national parks, sanctuaries, biosphere reserves). Ex situ protects them away from their natural home (zoos, seed banks, gene banks, breeding centres).
• National Park vs Botanical Garden: A national park is in situ (wild habitat protected). A botanical garden is ex situ (plants collected and grown elsewhere).
• Reintroduction vs translocation: Reintroduction puts a species back into an area where it once lived (often using captive-bred animals). Translocation moves wild animals from one wild place to another. India's cheetah project at Kuno National Park (2022) brought wild cheetahs from Namibia and South Africa, so it is a translocation-based reintroduction, not captive breeding.
• Seed bank vs gene bank: A seed bank stores seeds. A gene bank is the wider term and can store seeds, pollen, tissue, DNA or other genetic material.
• Captive breeding vs zoo display: A conservation breeding centre aims to release animals to the wild one day and avoids too much human contact. A display zoo mainly keeps animals for public education.

Issues, criticism and the way forward

• Habitat still matters most: Releasing birds or animals is pointless if the threat that killed them in the first place, such as power lines or poaching, is still there. Experts stress that ex situ must go hand in hand with fixing the habitat.
• Loss of wild behaviour: Animals raised by humans may not learn how to find food, avoid predators or choose mates. This is why "rewilding" training is needed before release.
• Small gene pool: Captive populations often start from very few founders. Over many generations they can lose genetic variety and suffer from inbreeding, which makes them weaker.
• High cost and long time: Breeding programmes need years of expert work and money, and success is never guaranteed.
• Disease risk: Keeping many rare animals in one place means one disease outbreak can hit the whole back-up population. Experts advise keeping more than one breeding centre.
• Way forward: Conservation scientists recommend a "one plan" approach in which in situ and ex situ work are planned together for each species, with clear goals for release, long-term tracking of released animals, and community support around release sites.

Concepts to Know

• Biodiversity: The variety of all living things (plants, animals, microbes) and the ecosystems they form.
• Habitat: The natural home of a plant or animal, which gives it food, water and shelter.
• Viable population: A population large and healthy enough to survive and keep breeding on its own over a long time.
• Founder population: The first small group of animals from which a captive population is bred.
• Inbreeding: Breeding between closely related animals. Over time it causes weak health and lower survival.
• Liquid nitrogen: Nitrogen gas cooled until it becomes liquid, at about minus 196°C. It is used to freeze and store living material for a very long time.
• IUCN Red List: A global list, run by the International Union for Conservation of Nature, that ranks species by how close they are to extinction.