Biodiversity Chapter 8

Rare Species

• narrow geographical range

• Occupies one or few specialized habitats

• Found only on small populations

Species that occupy a narrow rage are vulnerable to extinction example

• lynx

• Only a few hundred scattered through spain

Categories of endemism

• neoendemism

• Paleoendemics

Neoendemics

• species that occupy a small area or range because they have only recently evolved from closely related species

Example of neoendemics

• Cichlid fish in Lake Victoria of East Africa

paleoendemics

• ancient species with a narrow range whose close relatives have all gone extinct

Example of paleondemic

• the Giant Panda

5 categories used most in conservation planning

1. Species with a narrow geographical range

2. Species with only one or a few populations

3. Species with a small population

4. Species which population size is declining

5. Species that are hunted or harvested by people

Example of intensely harvested crop

• American ginseng (Panax quinquefolius)

10 lesser categories of species that are vulnerable to extinction

1. Species that need a large home range

2. Species with large bodies

3. Species that are not effective dispersers

4. Seasonal migrants

5. Species with little genetic variability

6. Species with specialized niche requirements

7. Species that are characteristically found in stable, pristine environments

8. Species that perform temporary or permanent aggregations

9. Species that have not had prior contact with people

10. Species that have closely related species that are recently extinct or are threatened with extinction

Allee Effect

• inability of a species to social structure to function once a population of that species falls below a certain number or density of individuals

International Union for Conservation of Nature (IUCN)

• a major international conservation organization that categorizes species in order to determine preservation actions

Red list criteria

• quantitative measures of threat based on the probability of extinction developed by the IUCN

Endangered species act

• The principal conservation law protecting species in the US

• 1973/1978/1982

• “To provide a means whereby the ecosystems upon which endangered and threatened species depend may be conserved and to provide a program for the conservation of such species”

Species that need a large home range

• lions

• Tigers

• Bears

• Elephants

• Giraffe

• Rhino

• Hippo

Species with large bodies

• lions

• Tigers

• Bears

• Elephants

• Giraffe

• Rhino

• Hippo

• Mammoth

Species that are not effective dispersers

• giant tortoise

• Lava lizard

Seasonal migrants

• birds

• Whales

Species with little genetic variability

• potato in ireland

• Koala

Species with specialized niche requirements

• clownfish

• Sea anemone

• Ocellated bird

Species that are characteristically found in stable, pristine environments

• Palm

Species that perform temporary or permanent aggregations

• prairie dogs

• Ciclid fish

Species that have not had prior contact with people

• deep ocean species

Species that have closely related species that are recently extinct or are threatened with extinction

• primates

• Cranes

• Sea turtles

• Orchids

Box 8.1

• decline in amphibian populations

• First World Congress on Herpetology in 1989 in Canterbury, England

• Human disturbance, pesticides, chemical pollution