Lecture 21

Conservation Biology

Conservation Biology

Integrative discipline that applies the principles of to the protection of

Defined as – scientific study of phenomena that affect the maintenance, loss, and restoration of biodiversity

Spearheading the effort

Alfred Russell Wallace

Dan Janzen

E.O. Wilson

Alwyn Gentry

Rate of loss estimations

Mostly indirect

Fossil record can be used to establish ‘background’ rate to which current rates can be compared

Species-area relationships

10% reduction  50% diversity reduction

Changes in conservation status over time

Endangered  Critically endangered

Rates of population decline or range contraction of common

Safe estimates

Worldwide (optimistic): ~ 100 spp / day become extinct (~ 27,000 / yr)

Current extinction rates parallel typical mass extinction events at the end of the Permian & Cretaceous periods

Whenever man has arrived large animals have gone extinct

HUMANS

Passenger pigeon

Extinction was sudden

Not gradual

Spread of & native generalists, coupled with declining abundances & distribution of native specialists

TAXONOMIC HOMOGENIZATION

Threats to biodiversity Habitat loss & degradation

Loss, fragmentation, degradation

Invasive species

Overexploitation

Pollution

Disease

Climate Change

Invasive species – those that are not native to an area, become naturalized, and have negative effects on function

Exotic Species Considered Invasive USDA

Overexploitation

Pollution & Disease

Fireproof Killer Whales

Biomes face different threats

Genetic Analyses

As we have seen, deleterious effects are more pronounced in small populations

Puma concolor coryi underwent ‘genetic rescue’

PVA

Examines population extinction risks

Moore et al. 2012 PVA of Trillium recurvatum

Conservation measures

Ex-situ conservation

Zoos

Direct introduction of new individuals

Extensive habitat manipulations

In-situ conservation

Habitat protection

Defending from

Legal issues

Endangered Species Act

Protects 1,300 native species in US & 570 from other countries Convention on International Trade in of Wild Fauna & Flora (CITES)

In effect for 35 yrs

167 countries involved

33,000 species receive some protection

How to rank species

Those in greatest risk are first on the list

Surrogate species

Surrogates – Species whose protection will indirectly protect other species with overlapping habitat requirements

Flagship species – Fuzzy, cute factor

Umbrella species – Typically require large areas, i.e., grizzly bears

Similar to surrogate

Assumes that protection of its habitat will serve as an ‘umbrella’ to protect many other species