Chapter 2 - Methods Of Conserving Biodiversity 2 (captive Breeding And Release Programmes)

Question 1

What is ex-situ conservation

Answer 1

• involves conservation away from where they would normally live
• often involves the breeding of species in captivity so that some of the young produced can be released to boost the wild population

Question 2

What factors influence the decisions about captive breeding programmes?

Answer 2

1) is the wild population threatened
2) is there a genetically diverse captive programme
3) is in-situ conservation being successful
4) is keeping a captive population realistic
5) is releases into the wild likely to be successful, now or in the future?

Question 3

Why might it be difficult to keep species in captivity?

Answer 3

1) habitat size - some species require such large habitats that they can’t be kept in captivity
2) food requirements - some species have feeding requirements that cannot be easily provided
3) species interrelationships - some species have complicated species interrelationships
4) financial constraints - keeping animals in zoos, or plants in biotic gardens, is expensive and there is not enough money available to keep all endangered species in captivity

Question 4

How are conditions for breeding a method to increase breeding success?

Answer 4

• the precise timing of breeding is vital to increase the survival chances of their young
• breeding is often triggered by stimuli such as day length, light level, temperature, and amount of food.
• if these aren’t provided, the animal may not breed

Question 5

How is population interactions a method to increase breeding success?

Answer 5

• in the wild, breeding pairs of many birds may choose isolation while non-breeding individuals live elsewhere
• in captivity, the mixing of breeding and non-breeding individuals may cause conflict and reduce the survival of eggs and chicks
• some species breed most successfully if breeding adults are separated from other adults

Question 6

How is artificial insemination (AI) a method to increase breeding success?

Answer 6

-involves the collection of semen from a make and it’s insertion into a female to produce offspring
✅ the semen can be stored for years so a male could father offspring long after he died
✅ animals don’t have to live in the same zoo, and one doesn’t have to be transported
✅ avoids the problem of mating partners nor accepting each other

Question 7

How is embryo transfer a method to increase breeding success?

Answer 7

• some mammal captive breeding populations have very few breeding females
• this slows the rate at which offspring can be produced because the duration of pregnancy can be long
• however, for some species, there may be a closely related species with a large number of females in captivity which can be used as surrogate mothers.

Question 8

What are the key features to a successful release programme?

Answer 8

1) large enough suitable habitat
2) reliable food supply
3) low predation risk
4) suitable breeding risk
5) water
6) support of local human population

Question 9

What is hard releases for captive breeding?

Answer 9

• involves releasing individuals with no post release support
• usually involves species where behaviour is controlled by instinct so that the individuals do not need to learn survival skills e.g, fish, reptiles

Question 10

What is soft releases for captive breeding?

Answer 10

• involves post release support such as gradual releases into larger areas and the provision of foods as they learn how to find food themselves
• often necessary for the release of mammals and birds