Captive Breeding and Translocation

What is ex-situ conservation?

Conservation that takes place ‘off-site’ or away from an organism’s natural habitat

What kind of species are most vulnerable for extinction?

• Large, charismatic mammals with large home ranges, hunting targets

• ground-nesting birds

• species that have narrow niches (islands, coastal marshes, mangroves)

What is the Allee effect?

positive feedback loop where the rate of population decline increases with decreasing density size

How many terrestrial vertebrate species will require captive breeding to prevent extinction in the near future?

2000-30000

What are the IUCN recognized contributions of captive breeding to conservation?

• establish secure populations

• educate public on conservation issues

• provide research opportunities

• source of animals for reintroduction

What does SSP stand for?

Species Survival Plans (SSP)

What are TAG’s?

Taxon Advisory Groups

What does the AZA do to help conservation?

• develop action plans and regional collection plans

• oversee species survival plans and studbooks

• establish research, conservation, and management priorities

• centralize pedigree records, mate choices, and exchange od individuals among institutions

How did zoos and botanical gardens start off?

They began as menageries for the ultra wealthy

What are some common themes among zoo mission statements?

• breed endangered species

• cooperate in conservation breeding programs with other zoos

• educate visitors about animal and conservation issues

• carry out scientific research

• support conservation of animals and their habitats in the wild

What are some of the challenges of ex situ conservation?

• Limited resources (space/funding)

• limited gene pool

• individuals with unknown pedigrees

• ad hoc breeding programs (instead of getting ideal founders before genetic issues)

• adaptivity to captivity/cultivation (hard to release into the wild)

• breakdown of cultural transmission, wild behavior, social structure

• potential for disease transmission

What are genetic management goals for captive breeding?

• maximize retention of genetic diversity over the long term

• minimize adaptation to captivity

What reduces the success of reintroduction?

• inbreeding depression

• loss of genetic diversity

• genetic adaptation to captivity

What are the 3 major phases in captive breeding programs?

1. Foundation Phase

2. Growth Phase

3. Maintenance Phase

What is the foundation phase?

The phase where efforts are focused to ensure all potential founders reproduce and where basic husbandry techniques are developed

What is the growth phase?

The phase that looks to maximize reproductive rates and ‘dispersal’ to multiple locations (mimicking gene flow)

What is the maintenance phase?

The phase that looks to maintain population growth at a predetermined target size, maintain population size to retain 90% of genetic diversity for 100 years, and reintroduce the population when it reaches target size

What is done to maximize N_e in captive populations?

• maintain population size and avoid fluctuations

• maximize effect breeding resources

• equalize sex-ratio among breeders

• maximize generation length and breed older animals to retain more genetic diversity

What are founders presumed to be in genetic management and why?

Presumed to be representative of wild populations to minimize changes to founder gene pool and freeze evolution in captive populations

What does minimizing kinship do?

reduces inequalities and acts as a method for retaining genetic diversity

What individuals are of highest value?

Ones with the lowest relatedness to overall populations

What is the kinship coefficient?

Probability that randomly drawn alleles in 2 individuals are IDB (Identical by Descent)

What is the kinship of 2 potential mates ?

It’s the inbreeding coefficient of their hypothetical offspring

What is the mean kinship breeding strategies?

the average relationship of an individual compared with the entire population

Which individuals are chosen as breeders?

Individuals with lowest mk (want to minimize mk)

Why are matings of individuals with very different mk are avoided?

• it limits future management options

• a high value mated with a low value will decrease the offspring value

What are possible selective scenarios for management of lethal alleles?

1. Ignore it

2. Minimize the phenotypic expression

3. Eliminate it by artificial selection

How is natural selection altered in captivity?

• ability to court/mate/reproduce in a new environment is altered

• potential for possible beneficial effects in captivity (increased fitness)

• prey capture/predator avoidance selection removes

• reduce selection for disease/parasites

What should be minimized to minimize the genetic adaptation to captivity?

• number of generations

• selection in captivity (mimic nature as much as possible)

What should be maximized to reduce genetic adaptation to captivity?

• proportion of wild immigrants

• frequency and timing of migrant introduction

• generation length

What were two main strong selection pressures found in the fish hatchery case?

• selection for immune function and wound repair (possibly due to overcrowding)

• metabolism (fed high calorie food)

What are the primary goals of ex situ genetic management?

1. minimize loss of genetic diversity

2. minimize adaptation to captive conditions

How can the goals of ex situ genetic management be achieved?

1. maximize representation of founder individuals

2. minimize mean kinship

3. minimize the number of generation in captivity