Lecture Twelve - Rarity and Red Listing Flashcards Preview

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Flashcards in Lecture Twelve - Rarity and Red Listing Deck (37)
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1
Q

What might habitat specitivity influence about a species’ range?

A

How widely a species exists within its geographic range.

2
Q

What is the extent of occurrence?

A

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

3
Q

What is the area of occupancy?

A

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

4
Q

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

A

They have a smaller area of occupancy

5
Q

Give the combination that produces a common species.

A
  • Large geographic range
  • Low habitat specitivity (being a generalist)
  • Large population size
6
Q

Who said that rarity is the precursor to extinction?

A

Darwin

7
Q

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

A

Every 5 years

8
Q

When can a species be declared extinct?

A

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

9
Q

Give a species that is extinct in the wild.

A

Scimitar-horned Oryx

10
Q

Give the three categories of threatened species.

A
  • Critical
  • Endangered
  • Vulnerable
11
Q

Give the risk of extinction of threatened species.

A

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

12
Q

Give the probability of extinction of critically endangered species.

A

50% probability in 5 years

13
Q

Give the probability of extinction of endangered species.

A

20% probability in 20 years

14
Q

Give the probability of extinction of vulnerable species.

A

10% probability in 100 years

15
Q

What is Criteria A for a threatened species?

A

Reduction in population size

16
Q

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

A

Four

17
Q

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

A

Indian Gharial

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

18
Q

What is Criteria B for a threatened species?

A

Decline of distribution or fluctuation

19
Q

How many categories of Criteria B are there?

How many must it meet?

A

There are 3 categories.

It must meet 2.

20
Q

What is criteria C for threatened species?

A

Small population size and decline

21
Q

Under what criteria does the Indian Gharial qualify as endangered?

A

A and C

22
Q

What is criteria D for threatened species?

A

Very small or restricted - less than 50 mature individuals.

23
Q

What is criteria E for critically endangered species?

A

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

24
Q

By what criteria does Nassau Grouper class as endangered?

A

Criteria A

25
Q

By which criteria does Ascension frigatebird class as vulnerable?

A

Criteria D

26
Q

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

A

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

27
Q

Give a Near Threatened UK species.

A

Common Otter

28
Q

Give the definition for Near Threatened.

A

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

29
Q

When did otters become Near Threatened?

A

2004

30
Q

Give an example of two Least Concern species.

A
  • Long Tailed Tit

- Eurasian Badger

31
Q

Give an example of a Data Deficient species.

A

Orcinus orca

32
Q

What proportion of species that have been assessed are threatened?

A

1/3

33
Q

What percentage of species are Data Deficient?

A

14%

34
Q

What percentage of amphibians are classified as threatened?

A

30%

35
Q

What is the Red List Index?

A

An index used to monitor the changing state of biodiversity.

36
Q

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?

A

It would decline by 1%.

37
Q

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

A

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