Conservation Biology Lecture Notes

What is Conservation Biology

• A discipline focused on the effects of environmental change on biological diversity.
• Utilizes evidence-based approaches to anticipate, prevent, minimize, and repair ecological damage.

Multiple Disciplines Involved

• Science:
  • Ecology
  • Animal behaviour
  • Biogeography
  • Systematics
  • Genetics
  • Evolution
  • Epidemiology
  • Forestry
  • Fisheries
  • Wildlife biology
• Social Sciences:
  • Economics
  • Policy development
  • Ethnobiology
  • Environmental ethics
• Traditional Knowledge:
  • Oral histories
  • Stories
  • Direct experiences

Biodiversity Loss: The Context

1. Species Count:
   • About 2 million species formally described.
   • True estimates range from 10-50 million species.
2. Historical Extinction Rates:
   • 2-5 marine families disappear every million years.
   • Loss of approximately 1 species per million - 10 million species present since Cambrian.

Species Extinctions Since 1600

• Expected given the background extinction rate
  

• Human Impact:
  • Increasing population size leads to increased resource consumption.
  • Habitat destruction, overexploitation, pollution, introduced species, and climate change.

Consequences of Human Population Increase x Consumption

1. Habitat Destruction:
   • Degradation and fragmentation due to agriculture, urban sprawl, mining, etc.
   • ~65% of tropical forests lost.
   • Caribbean coral is disappearing at a rate of ~10% per year.
2. Overexploitation:
   • Unsustainable extraction of resources including fishing and logging.
3. Introduced Species:
   • Non-native species encroach on habitats, often disrupting native biodiversity.
4. Pollution:
   • Widespread effects from urban development, transportation, and industry.
5. Climate Change:
   • Impacts include phenological changes and range shifts of species.

Importance of Biodiversity

• Ecosystem Services:
  • Supporting Services: Nutrient cycling, soil formation, photosynthesis.
  • Provisioning Services: Clean water, food, fisheries, and raw materials like wood.
  • Regulating Services: Flood control, air purification, carbon storage, and pollination.
  • Cultural Services: Aesthetic, recreation, and mental well-being benefits from nature.
• Economic Value of Biodiversity
  • Earthworms contribute ~$5 billion annually in agriculture.
  • Global economic benefits of biodiversity estimated at $3 trillion per year (11% of total world economy).

Canadian Context

• Species at Risk Act:
  • Managed by COSEWIC, an independent body assessing species status in Canada based solely on science and traditional knowledge.
• Species Diversity Statistics:
  • B.C. is the most biodiverse province with 2,500 vascular plants, 60,000 invertebrates, and 563 vertebrates.
  • Significant threats include habitat loss and specific endangered species like the Vancouver Island Marmot (endemic with about 200 individuals in the wild).

Conservation Strategies

• Island Biogeography Theory:
  • Larger reserves better for biodiversity than smaller ones.
  • Proximity to other reserves aids in conservation strategies.
  • Movement corridors can connect habitat fragments and enhance genetic exchange.