NRES 348 — Lec 7: Conservation Biology

What is conservation biology?

An integrated approach to the protection & management of biodiversity.

What is biodiversity?

The variety of life at all levels, including genes, species, communities, ecosystems, & landscapes.

What are 3 characteristics of conservation biology?

It is a “Crisis Discipline”, multidisciplinary & inexact, & value-laden (influenced by human values).

Why did conservation biology develop?

Increasing human population growth, habitat loss, ecosystem degradation, & species extinction.

What is habitat fragmentation?

The reduction of habitat into smaller, more isolated patches.

What are the main negative effects of habitat fragmentation?

Fewer species, increased edge effects, & greater risk of local extinction.

What are edge effects?

Changes in environmental conditions along habitat boundaries, such as increase light, temperature changes, & predation.

What is the relationship between habitat patch size & species richness?

Larger habitat patches generally support more species, while smaller patches support fewer.

What is the difference between demographic & environmental stochasticity?

• Demographic = random differences in individual survival & reproduction.

• Environmental = random environmental changes affecting population survival & reproduction.

What is a metapopulation?

A group of semi-isolated populations connected by migration or gene flow, where local populations can go extinct & be recolonized.

What is the difference between a source & a sink population?

• Source: reproduction exceeds mortality (lambda > 1)

• Sink: mortality exceeds reproduction (lambda < 1)

What does SLOSS stand for?

Single Large Or Several Small — a debate about which reserve design better protects biodiversity.

What is biotic homogenization?

When ecosystems become more similar because generalist & invasive species spread while specialized species disappear.

What are the major threats to biodiversity?

Habitat loss, invasive species, human activities, & climate change.