Captive Breeding Management Flashcards
Define Allele
alternative form of a gene
Define diversity
number of alleles per locus
Define effective population size (Ne)
The size of a randomly mating population of
constant size with an equal sex ratio and a Poisson distribution of family
sizes that would result in the same rate of genetic drift as that observed in
the population under consideration. In its simplest form the Ne
is the
number of breeding adults in the population
Define Gene diversity (expected heterozygosity)
the heterozygosity expected if a random mating population were in hardy- Weinberg equilibrium
Define Genetic drift
Loss of alleles through random sampling of the population through Mendelian inheritance
define natural selection
The differential fitness between members of a species
possessing adaptive characteristics, and those without adaptive
characteristics
What is a Studbook?
Entire (captive) history of a population or species
includes:
- Major life history (birth, death…)
- Individual identifiers (ear tags/ microchips)
- Parentage (pedigree to founder)
Who keeps SB?
- World Association of Zoos & Aquaria
- International studbooks
- Regional zoo& aquaria associations (European (EAZA)), American, Australian..)
- Research institutions
Studbook Keeper reports to who?
EAZA Taxon Advisory Group (TAG) or WAA Conservation Coordination
What is the role of a SB keeper?
- Data compiled automatically by species360
- Collate additional data from non-member oos
-ZIMS module - Publish to studbook
How are SBs used?
- Population management (EEP)
- Identification of problem
-Research
What tools for SB keeper?
- ZIMS (zoo info management system)
- Word
- Communication tools
What is an EEP?
- European Ex-Situ Programme
- Intensive population management within a region
What is the role of an EEP coordinator ?
- Maximise genetic diversity (heterozygosity & allelic diversity)
- Equalise founder representation
- Minimise inbreeding, genetic drift & adaptation to captivity - Maintain demographic stability
- Provide animals for reintroduction, if appropriate -> breeding recommendations
What are the stages of captive breeding ?
- Founding phase
- Growth phase
- Capacity or maintenance phase
ONCE CAPACITY HAS BEEN REACHED …?
RETINTRODUCTION MAY BECOME AN OPTIONS
What happens genetically to adapt to captivity
- Selection will eliminate alleles that are maladaptive in the captive environment (antelope flight response)
STRONG selection pressure
What will result from drift?
Cumulative loss of both adaptive and maladaptive alleles
What happens in Founder phase of captive propagation?
- Acquire representation of wild populations when numbers are still in thousands
- But catchups occur when population v small
Recommendation: >20 unrelated founders
What reality of founder phase
Catchups from limited area,s few founders, not all wild-caught animals have reproduced => loss of genetic diversity
Describe the growth phase of captive propagation
- Minimising loss of founder alleles if all founders contribute equal number of offspring
- 7-12 offspring needed to ensure 99% chance that all founder allles retained
- SHould fill all spaces asap (in 1 generation)
What is the reality of growth phase?
all founders do not produce equal progeny, not
enough offspring per founder, growth may be slow =>
loss of founder alleles & genetic diversity
Describe the capacity phase of captive ropagation
- Imbamance in founder representation can be rectified
- Priority for breeding given to animals that are most likely to have rare alleles
-Minimum Ne should be above 50 short term & 1000-5000 long term
Reality of capacity phase ?
Addressing founder imbalance require co-operations of zoos, Ne<1000 for all programmes
What are some challenges with demographic management ?
- Growth exceeds capacity
- Unequal male:female ratio
- Mortality
- Unstable age distribution
- Variable or negative growth raes
What tools to manage captive population
ZIMS & MNx (population management x)
Describe PMx software
- Uses pedigree data to quantify relatedness within a population & estimate GD loss
- Model the effects of various mating choices
- Mean kinship & inbreeding coefficients
When we set goals on PMX what is default?
90% GD for 100 yrs but each EEP should set a goal that is realistic for that population
What two optiosn do we have in reproductive planning?
- How many spaces are there in EEP institutions?
- How many individuals do you need to meet goals?
What will PMx tell you ?
How many litters needed, how many breeding pairs and how many births needed
What is the average kinship?
Relatedness of an individual with all individuals in the population, including itself
What is range of inbreeding coefficient (F) ?
from 0.00 to 1.00 (2 siblinds= 0.25 F
How do we make our breeding recommendations?
Choose matings between animals of equal and low mean kinship
What is the reality for breeding recommendations ?
- social considerations
- Logistics
- Legislation
- Animal bhvr
-Permits - Politics
- Animal health
- Co-operation
- Facilities & carrying capacity
- Appearance
- Cost
