In Situ Conservation involves protecting species within their natural habitats. This is often achieved by establishing National Parks or Marine Conservation Zones where human activity is restricted to prevent habitat destruction.
Active management within these areas may include controlling invasive species that outcompete native flora and fauna. It also involves restoring degraded habitats, such as replanting native woodlands or re-flooding wetlands to encourage the return of specific species.
Legal protections are often applied to specific endangered species within these zones, making it illegal to hunt, collect, or disturb them. This method is preferred because it allows species to continue evolving alongside their natural predators and competitors.
Ex Situ Conservation involves removing organisms from their natural environment to be protected in controlled settings. Common examples include botanic gardens, zoos, and aquariums, which serve as refuges for species that can no longer survive in the wild.
Seed Banks are a critical ex situ technique where seeds are dried and stored at sub-zero temperatures (typically ). This allows for the long-term preservation of plant genetic diversity in a very small space, providing a backup if wild populations go extinct.
Captive Breeding Programs aim to increase the population size of endangered animals with the ultimate goal of reintroducing them into the wild. These programs must carefully manage breeding to maintain genetic diversity and prevent inbreeding depression.
| Feature | In Situ Conservation | Ex Situ Conservation |
|---|---|---|
| Location | Natural habitat | Artificial environment (Zoos, Banks) |
| Evolution | Species continue to adapt to environment | Evolutionary process is often halted |
| Cost | Generally lower per species | High (infrastructure and maintenance) |
| Risk | Vulnerable to local disasters/poaching | Vulnerable to technical failure (e.g., power loss) |
| Space | Requires large areas of land | Requires very little space (e.g., seed banks) |
Distinguish the 'Why': When asked why biodiversity should be maintained, categorize your answer into ecological, economic, and ethical points to ensure full marks. Don't just list examples; explain the underlying benefit (e.g., 'maintaining genetic resources for future medicines').
Seed Bank Mechanics: Remember that seeds in banks are regularly tested for viability. If germination rates drop, the seeds are grown into plants to produce a fresh batch of seeds for storage.
Common Error: Students often confuse 'species richness' (number of species) with 'species evenness' (relative abundance). A truly biodiverse area requires both high richness and high evenness.
International Agreements: Be prepared to discuss the role of CITES (regulating trade of endangered species) and the Rio Convention on Biological Diversity (global commitment to sustainable use and conservation).
