One of the potential problems with supplementing endangered wildpopulations with captive bred individuals is that captive bredorganisms often have reduced fitness compared to their wildcounterparts. Reasons for this are varied, but work suggests it isa combination of reduced genetic variation in captive bredpopulations (small population sizes and assortative mating leadingto reduced genetic variation) as well as reduced fitness due toindividuals adapting to a captive environment as opposed to a wildenvironment. Fundy Atlantic salmon (Salmo salar) are anendangered salmon species whose numbers have declined to a pointthat scientists started to supplement their wild numbers withcaptive bred individuals. The question you will answer here is:is supplementing wild salmon populations with captive-bredindividuals beneficial if the captive bred individuals have lowerfitness than the wild population?
The average number of eggs laid by females in the wildpopulation is about 2,500/female. The captive bred individualstypically exhibit about 30% lower fecundity than wild individuals(some estimates are up to 40% lower, but we will use 30% forpurposes of this assignment).
1. If the heritability of fecundity is 0.1, what do you predictthe fecundity of the new population will be (assume you add just asmany new individuals as were already in the wild population)? (2points)
2. Now consider if the heritability of fecundity was higher,let’s say 0.3 Now what do you predict the fecundity of the newpopulation will be (using all the original numbers, not after onegeneration of selection)? (2 points)
3. If fecundity exhibits high heritability, what do you predictwill happen to population numbers in this population over time ifcaptive bred individuals are added every year (2 point)?
