Genetic Management of Fragmented Animal and Plant Populations: Chapter Summaries

Genetic Management of Fragmented Populations

Involves applying evolutionary genetic theory to address inbreeding and loss of genetic diversity in small isolated populations.

Fragmented Distributions

Result from human activities, leading to small isolated populations with increased inbreeding, reduced genetic diversity, and elevated extinction risks.

Inbreeding Depression

Occurs in naturally outbreeding species due to inbreeding, reducing survival and reproduction, increasing extinction risk.

Augmenting Gene Flow

Reverses inbreeding depression, loss of genetic diversity, and evolutionary potential by introducing genetic diversity from different populations.

Outbreeding Depression

Occurs occasionally from crossing between populations but is predictable and less severe than inbreeding depression.

Temporary Outbreeding Depression

Often temporary as natural selection removes harmful effects in most cases.

Unsuitable Species Definitions

Phylogenetic and General Lineage Species Concepts are unsuitable for conservation; recommend using reproductive isolation for delineations.

Standardized Delineation Protocols

Urged for conservation purposes to include appropriate species concepts, sampling regimes, and statistical analyses.

Population Differentiation

Important to distinguish between drift and differential adaptation when managing gene flow among populations.

Genetic Rescue

Recommend augmenting gene flow for outbreeding species suffering inbreeding and low genetic diversity if benefits outweigh costs and risks.

Fitness Benefits

Fitness benefits from crossing may not persist in selfing and mixed mating species as in outcrossing species.

Genetic Management Actions

Assess risks and benefits of different scenarios; inaction can harm population persistence.

Managing Gene Flow

Minimize mean kinship among isolated populations to maximize genetic diversity if kinship analyses are not feasible.

Adaptability

Species need to be more adaptable to cope with global environmental change, increasing the need for genetic management.

Integrated Management

Threatened species require integrated management across populations, disciplines, and political boundaries for effective conservation.