Lecture Twelve - Rarity and Red Listing

Question 1

What might habitat specitivity influence about a species’ range?

Answer 1

How widely a species exists within its geographic range.

Question 2

What is the extent of occurrence?

Answer 2

The total area that is included within the limits of the geographic range.

Question 3

What is the area of occupancy?

Answer 3

Thea area where populations of the species occur within the geographic range.

Question 4

What can be said about specialist species for a given size of geographic range?

Answer 4

They have a smaller area of occupancy

Question 5

Give the combination that produces a common species.

Answer 5

• Large geographic range
• Low habitat specitivity (being a generalist)
• Large population size

Question 6

Who said that rarity is the precursor to extinction?

Answer 6

Darwin

Question 7

In the IUCN Red List, how often are species assessed?

Answer 7

Every 5 years

Question 8

When can a species be declared extinct?

Answer 8

When there is no doubt that the last individual has died after systematic exhaustive surveys

Question 9

Give a species that is extinct in the wild.

Answer 9

Scimitar-horned Oryx

Question 10

Give the three categories of threatened species.

Answer 10

• Critical
• Endangered
• Vulnerable

Question 11

Give the risk of extinction of threatened species.

Answer 11

Minimum risk of extinction of 10% probability within 100 years.

Question 12

Give the probability of extinction of critically endangered species.

Answer 12

50% probability in 5 years

Question 13

Give the probability of extinction of endangered species.

Answer 13

20% probability in 20 years

Question 14

Give the probability of extinction of vulnerable species.

Answer 14

10% probability in 100 years

Question 15

What is Criteria A for a threatened species?

Answer 15

Reduction in population size

Question 16

How many ways are there in which criteria A for extinction can be defined?

Answer 16

Four

Question 17

Name a species that qualifies as critically endangered under Criteria A.

Answer 17

Indian Gharial

>80% reduction in population size leading up to 2007.

Question 18

What is Criteria B for a threatened species?

Answer 18

Decline of distribution or fluctuation

Question 19

How many categories of Criteria B are there?

How many must it meet?

Answer 19

There are 3 categories.

It must meet 2.

Question 20

What is criteria C for threatened species?

Answer 20

Small population size and decline

Question 21

Under what criteria does the Indian Gharial qualify as endangered?

Answer 21

A and C

Question 22

What is criteria D for threatened species?

Answer 22

Very small or restricted - less than 50 mature individuals.

Question 23

What is criteria E for critically endangered species?

Answer 23

A probability of extinction of 50% over 10 years/3 generations

Question 24

By what criteria does Nassau Grouper class as endangered?

Answer 24

Criteria A

Question 25

By which criteria does Ascension frigatebird class as vulnerable?

Answer 25

Criteria D

Question 26

How does a species qualify as Near Threatened or Least Concern?

Answer 26

No evidence of over 10% extinction risk in 100 years.

Question 27

Give a Near Threatened UK species.

Answer 27

Common Otter

Question 28

Give the definition for Near Threatened.

Answer 28

Close to qualifying for a threatened category and likely to qualify in the future.

Question 29

When did otters become Near Threatened?

Answer 29

2004

Question 30

Give an example of two Least Concern species.

Answer 30

• Long Tailed Tit

- Eurasian Badger

Question 31

Give an example of a Data Deficient species.

Answer 31

Orcinus orca

Question 32

What proportion of species that have been assessed are threatened?

Answer 32

1/3

Question 33

What percentage of species are Data Deficient?

Answer 33

14%

Question 34

What percentage of amphibians are classified as threatened?

Answer 34

30%

Question 35

What is the Red List Index?

Answer 35

An index used to monitor the changing state of biodiversity.

Question 36

If there are 100 species at the beginning, and all but one stayed the same in 5 years, what would the Red List Index be?

Answer 36

It would decline by 1%.

Question 37

What is the difference between Living Planet Index and Red List Index?

Answer 37

Living Planet Index is based on vertebrate population sizes, as opposed to Red List Index which is based on Red List status.