Arguments for Conservation
Biodiversity has value for many different reasons, and conservation arguments draw on all of them. The IB groups these into five categories: aesthetic, ecological, economic, ethical, and social.
The beauty, inspiration, and emotional resonance that natural environments provide to people, expressed through art, literature, recreation, and personal experience.
The contribution a species or habitat makes to ecosystem functioning, including nutrient cycling, pollination, climate regulation, and water purification.
The financial worth of biodiversity as natural capital, including income from ecotourism, pharmaceutical and agricultural genetic resources, and the monetary value of ecosystem services.
A justification for conservation based on moral grounds. Ethical arguments divide broadly into intrinsic value (nature has worth in itself, regardless of human use) and instrumental value (nature is valuable because it serves human or other ends).
Social arguments focus on the goods and services that ecosystems provide for human well-being: food security, clean water, cultural identity, and physical and mental health.
These five categories are not separate in practice. Ecotourism, for example, draws simultaneously on aesthetic appeal, economic return, and social benefit. In an exam response, identifying which justifications apply to a given case, and showing how they interact, earns more marks than simply listing them.
Economic arguments frequently invoke natural capital as a framing device. Ecosystem services have been estimated to be worth tens of trillions of dollars annually, though such valuations are contested.
The point is that when ecosystem services disappear, replacing them technologically is often impossible or prohibitively expensive.
Species-Based and Habitat-Based Conservation
Conservation strategies fall into two broad categories depending on whether the focus is the species itself or the habitat it depends on.
The protection of species outside their natural habitat, typically in controlled facilities such as zoos, botanic gardens, or seed banks.
The protection of species within their natural habitat, through measures such as national parks, nature reserves, and wildlife sanctuaries.
These two approaches address different problems. Ex situ strategies are most useful when a species is critically endangered and its habitat is too degraded or unsafe to support it. In situ strategies address the root cause of most biodiversity loss, which is habitat destruction, and preserve the ecological interactions that a species depends on.
Ex situ measures include:
- Zoos and captive breeding programmes: Maintain viable populations of endangered species, support scientific research, and educate the public. Reintroduction to the wild is possible but challenging. Animals may suffer welfare costs in captivity, and running these facilities is expensive.
- Botanic gardens: Conserve living plant collections and support research and public education. Kew Gardens in London, for example, holds one of the world's largest living plant collections.
- Seed banks: Store seeds at low temperature and humidity to preserve plant genetic diversity. The Svalbard Global Seed Vault in Norway holds over 1.3 million seed samples and acts as a global backup against crop failure, disease, or habitat loss. Seeds may not remain viable indefinitely, and questions of ownership and access between high-income and low-income countries remain unresolved.
- CITES (Convention on International Trade in Endangered Species of Wild Fauna and Flora): An international treaty that regulates and restricts trade in wild plants and animals to prevent overexploitation. It lists species across three appendices reflecting their level of threat.
In situ measures include:
- National parks: Large protected areas where ecosystems and species are conserved within their natural environment. Yellowstone National Park in the USA protects species such as bison, wolves, and grizzly bears while preserving unique geothermal habitats.
- Nature reserves and wildlife sanctuaries: Designated areas with varying levels of legal protection and management intensity, from strict no-entry zones to areas allowing limited sustainable use.
Not all protected areas are equally effective. Legal designation alone does not guarantee conservation success. The size, shape, management quality, and degree of enforcement all determine whether a protected area actually conserves biodiversity.