Chapter 13 Part 3

Question 1

what are metapopulations composed of

Answer 1

subpopulations that can experience independent population dynamics across space

Question 2

Preferred habitat often occurs as

Answer 2

patches of suitable habitat surrounded by a matrix of unsuitable habitat

Question 3

Habitat fragmentation

Answer 3

the process of breaking up large habitats into a number of smaller habitats

Question 4

habitat fragmentation often occurs as the result of

Answer 4

human activities (e.g., clearing forests, road construction, draining wetlands)

Question 5

some habitat fragments experience extinctions, whereas others are

Answer 5

colonized by dispersers

Question 6

The basic (first) metapopulation model assumes that

Answer 6

all habitat patches are equal in quality and that the matrix between patches is inhospitable.

Question 7

Sources

Answer 7

high-quality patches that produce a large number of individuals that disperse to other patches

Question 8

Sinks

Answer 8

low-quality patches that produce few individuals and rely on dispersers to keep the sink population from going extinct

Question 9

If subpopulations rarely exchange individuals, fluctuations in abundance will be

Answer 9

independent among subpopulations

Question 10

If subpopulations frequently exchange individuals, the subpopulations will

Answer 10

act as one large population

Question 11

With intermediate patch connectivity, abundance in one subpopulation can influence

Answer 11

the abundance of other subpopulations

Question 12

Assume that habitat patches are

Answer 12

of equal quality, each occupied patch has the same subpopulation size, and each subpopulation supplies the same number of dispersers to other patches

Question 13

The proportion of occupied patches when colonization and extinction have reached an equilibrium (𝑝̂) is represented as:

Answer 13

𝑝̂ = 1 - (e/c)

Question 14

We can increase the number of occupied habitat patches by

Answer 14

providing corridors between patches to increase the rate of colonization (c)

Question 15

p

Answer 15

the fraction of habitat patches that is occupied

Question 16

e

Answer 16

the probability of each patch becoming unoccupied (i.e., going extinct)

Question 17

c

Answer 17

the probability of a patch becoming colonized

Question 18

We can also increase the number of occupied patches by decreasing

Answer 18

rates of extinction (e)

Question 19

Hence, species may be preserved by protecting

Answer 19

large fragments of habitat that reduce extinction risk, or by ensuring that individuals can disperse to and from patches.

Question 20

Habitat patches are rarely equal in quality;

Answer 20

some patches are larger or contain a higher density of resources

Question 21

Small patches are likely to experience

Answer 21

higher rates of extinction and are less likely to be occupied than large patches

Question 22

Dispersal success is inversely related to

Answer 22

the distance of dispersal; hence, more distant patches will have a lower probability of being occupied than closer patches.

Question 23

Unoccupied patches that are close to occupied patches are more likely to be

Answer 23

colonized

Question 24

Rescue effect

Answer 24

when dispersers supplement a declining subpopulation and thereby prevent it from going extinct

Question 25

Less isolated patches are more likely to be

Answer 25

rescued and are also more likely to be colonized

Question 26

After settlement of farmers in western United States, habitat loss substantially reduced the number of

Answer 26

black-footed ferrets

Question 27

what reduced numbers even more

Answer 27

poisons and disease

Question 28

In 1981, a small population in Wyoming was discovered and a captive breeding program was very successful

Answer 28

Using metapopulation theory, biologists conducted several reintroductions in locations throughout western North America. This created a metapopulation that was resistant to complete extinction