Reintroductions

Question 1

What is the important role of captive populations?

Answer 1

• To re-establish or supplement wild populations whilst maintaining genetic diversity in captivity

Question 2

What must captive populations do when re-establishing wild population?

Answer 2

• Maintain genetic diversity

- Be self-sustaining

Question 3

What must be done to the habitat for animal species to be reintroduced successfully?

Answer 3

Habitat restoration/ conservation

Question 4

What are 2 advantages of Reintroduction

Answer 4

• Method of increasing numbers of individuals – prevent extinction
• Increases knowledge of species biology
• If captive breeding can allow for a self-sustaining population, reduces need to take more from the wild
• Can help gain support – financial and political

Question 5

What are 2 disadvantages of reintroduction

Answer 5

• Initial stock can damage wild population
• Poor facilities for breeding in captivity
• Maintain a large enough population size to prevent genetic drift and loss of variability
• Selection of captive population making them better fit for captivity than wild environment
• Susceptibility to disease – high concentrations of individuals
• Difficult to get some species to breed in captivity

Question 6

Name a species that is particularly problematic to breed in captivity

Answer 6

Hawksbill Turtle
Takes 25-40 years to reach sexual maturity - has very precise mating rituals and reproductive is determined by seasonality/ weather

Question 7

What are the steps to re-releasing a species

Answer 7

Feasibility study and background research
Previous reintroductions review
Identify choice of release site and types
Evaluation of reintroduction site
Number of reintroduction sites
Availability of suitable release stock
Release of captive stock
Socio-economic and legal requirements
Planning, preparation and release stages
Post-release activities
Genetic management of released population

Question 8

how did a captive breeding program save The Mauritius Pink Pigeon?

Answer 8

• Only 10-20 individuals left in 1980
• Initate captive breeding
• Released 1987
  by 1995 population recovered and increased up to 50% per year

Question 9

Define Soft Release of species

Answer 9

A gradual and supported reintroduction to improve the success of animals released into an unfamilliar wild environment
- i.e: acclimitisation

Question 10

Define Hard Release of species

Answer 10

An initial reintroduction without human support

Question 11

Name 2 animals that are better at hard releases

Answer 11

Snakes

Iguanas

Question 12

Name 2 animals that are better at soft releases

Answer 12

Howler monkeys

Primates

Question 13

What is reinforcement in reintroductions

Answer 13

Adding individuals to an existing population to increase size, genetic diversity and prevent fragmentation

Question 14

What are 3 positives of reinforcement?

Answer 14

• Increases existing population size
• Increases genetic diversity
• Prevents fragmentation

Question 15

What are 3 negatives of reinforcement?

Answer 15

• Disease spread
• deleterious genes
• can reduce diversity due to predation or competition

Question 16

What is translocation of species?

Answer 16

The deliberate movement of species for conservation purposes

Question 17

Name a species that has benefited for translocation

Answer 17

Seychelles warbler

Howler monkey

Question 18

What is the dilution effect

Answer 18

When newly introduced populations negatively effect wild populations by causing outbreeding depression

Question 19

Name 3 things wild environments often select for

Answer 19

Ability to court, mate, breed and develop
Flightiness and fear to humans
Prey capture and predator avoidance
Disease and parasite resistance

Question 20

How does captivity cause genetic adaptation?

Answer 20

Often rare/ deleterious alleles in the wild become favoured in captivity, causing genetic adaptation

Question 21

Name 3 ways we can minimise the effects of genetic adaptation in captivity

Answer 21

Minimise:
Number of generations in captivity (gene banks)
The magnitude of selection in captivity
Genetic variations within populations
The size of captive populations
Maximising the proportion of wild immigrants in recent generations
Make captive habitat similar to wild – often difficult if wild habitat is harsh.

Question 22

What is supportive breeding?

Answer 22

Supportive breeding is the boosting of a wild population’s size by breeding part of the population in captivity and releasing the captive progeny back into the wild

Question 23

If carried out poorly, what are 3 negative impacts of supportive breeding?

Answer 23

Reduced wild population size
Reduced reproductive fitness
Inbreeding depression

Question 24

What percentage of reintroduction programmes are successful (Beck et al , 1994)

Answer 24

11%

Question 25

What other technique can improve the success of reintroductions?

Answer 25

Translocation

Question 26

Why is data on reintroduction success so scarce?

Answer 26

• Quantitative evaluations of reintroductions are infrequent and often abandoned
• Lack funding

(Muths et al, 2014)