Two Pathways to Saving Biodiversity
Conservation biology offers two broad strategic approaches to protecting threatened species: in-situ conservation, which protects species within their natural habitats, and ex-situ conservation, which maintains species outside their natural environments in controlled facilities. Understanding the distinction between these approaches — and recognising their complementary roles — is essential both for practical conservation and for NEET examination success.
In-situ conservation is the foundation of biodiversity protection. By preserving intact ecosystems, in-situ methods conserve not just the target species but entire communities of organisms, their ecological interactions, evolutionary processes, and natural behaviours. India's in-situ network is extensive: 18 biosphere reserves (the first and largest being the Nilgiri Biosphere Reserve, established 1986), 106 national parks (the oldest being Jim Corbett, established 1936), and approximately 566 wildlife sanctuaries. National parks represent the strictest form of in-situ protection under the Wildlife Protection Act (1972) — no human activities are permitted within park boundaries. Wildlife sanctuaries are somewhat less strictly protected, allowing limited human activities such as grazing and harvesting of minor forest produce; they were often established over inhabited land, necessitating accommodation of pre-existing land use. Biosphere reserves follow a three-zone model: a strictly protected core zone, a buffer zone allowing limited research and education, and an outer transition zone where sustainable human use, settlement, and tourism are permitted.
Sacred groves deserve special mention because they are frequently misclassified in NEET examinations. Forest patches in Meghalaya's Khasi and Jaintia Hills, Rajasthan's Aravalli Hills, and the Western Ghats are protected by local communities through religious taboos against cutting or disturbing the grove. Although the management is cultural rather than governmental, the conservation mechanism is in-situ — species are protected in their natural habitat. This makes sacred groves a form of community-based in-situ conservation, not ex-situ.
Ex-situ conservation becomes necessary when species' wild populations have declined to critically small sizes, making in-situ protection alone insufficient. Methods include zoological parks (captive breeding of endangered animals), botanical gardens (cultivation of rare and endangered plant species outside natural habitat — the Indian Botanical Garden in Howrah exemplifies this), seed banks (where seeds can be stored almost indefinitely at −196 °C in liquid nitrogen — the temperature of cryopreservation), gene banks (storing genetic material of crops and wild species), and tissue culture or micropropagation of endangered plant species. The Svalbard Global Seed Vault in Norway serves as a global backup for seed banks worldwide.
The key distinction is not who manages the conservation (government vs. community vs. corporation) but whether species remain in their natural habitat (in-situ) or are removed to a controlled facility (ex-situ). This distinction is the source of the most common NEET error regarding sacred groves.
Both approaches are necessary and complementary: in-situ conservation is the preferred strategy for maintaining self-sustaining wild populations, while ex-situ conservation provides a critical safety net for species on the brink of extinction in the wild, with reintroduction programs aiming to eventually return ex-situ populations to in-situ habitats.