Introduction to Conservation Biology
Key concepts, goals, and tools for preserving biodiversity
1. What Is Conservation Biology?
| Aspect |
Description |
| Definition |
The scientific study of protecting and restoring Earth’s biodiversity and the ecological processes that sustain it. |
| Scope |
Species, populations, communities, ecosystems, and genetic diversity. |
| Interdisciplinary |
Integrates ecology, genetics, evolution, sociology, economics, law, and policy. |
| Goal |
Maintain the ability of natural systems to provide ecosystem services and support life‑supporting processes now and in the future. |
2. Why Conservation Biology Matters
| Reason |
Example |
| Biodiversity loss |
~1 million species face extinction in the next few decades (IPBES 2020). |
| Ecosystem services |
Pollination, water purification, carbon sequestration, climate regulation. |
| Human well‑being |
Food security, medicines, cultural values, recreation. |
| Ethical responsibility |
Stewardship of Earth’s living heritage for future generations. |
3. Core Concepts
| Concept |
Explanation |
Typical Metric |
| Species richness |
Number of different species in a defined area. |
Species count |
| Species evenness |
How equally individuals are distributed among species. |
Shannon’s evenness index |
| Genetic diversity |
Variation of genes within and among populations. |
Heterozygosity, allelic richness |
| Population viability |
Likelihood a population will avoid extinction over a given time. |
Extinction probability, Population Viability Analysis (PVA) |
| Habitat fragmentation |
Breaking of continuous habitat into smaller, isolated patches. |
Edge‑to‑core ratio, connectivity indices |
| Ecological resilience |
Capacity of an ecosystem to absorb disturbance and retain function. |
Recovery time, resistance thresholds |
4. Threats to Biodiversity
| Category |
Main Drivers |
Representative Examples |
| Habitat loss & degradation |
Agriculture expansion, urbanization, mining. |
Deforestation in the Amazon |
| Overexploitation |
Hunting, fishing, logging, wildlife trade. |
Overfishing of Atlantic cod |
| Invasive species |
Non‑native organisms outcompeting natives. |
Cane toads in Australia |
| Pollution |
Chemical runoff, plastic debris, air pollutants. |
Coral bleaching from nutrient enrichment |
| Climate change |
Temperature rise, altered precipitation, sea‑level rise. |
Range shifts of alpine plants |
| Disease |
Emerging pathogens affecting wildlife. |
White‑nose syndrome in bats |
5. Conservation Strategies
5.1 In‑situ Conservation
Protect species and ecosystems in their natural habitats.
| Tool |
Description |
Typical Application |
| Protected Areas (PAs) |
National parks, reserves, wildlife sanctuaries. |
Preserve core habitats; often 15–17 % of land surface. |
| Habitat Restoration |
Reforestation, wetland creation, coral reef transplantation. |
Reconnect fragmented landscapes. |
| Ecological Corridors |
Linear habitats linking isolated patches. |
Facilitate gene flow for large mammals. |
| Species Management Plans |
Targeted actions (e.g., captive breeding, translocation). |
Recovery of the California condor. |
| Community‑Based Conservation |
Involves local people in stewardship and benefit‑sharing. |
Community forest management in Nepal. |
5.2 Ex‑situ Conservation
*Maintain