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Trapped in the extinction vortex? Strong genetic effects in a declining vertebrate population
Donald Blomqvist1, Angela Pauliny, Mikael Larsson
1Department of Zoology, University of Gothenburg, Box 463, Gothenburg 40530, Sweden. donald.blomqvist@zool.gu.se
BMC Evolutionary Biology
|February 4, 2010
Summary
Inbreeding and reduced genetic diversity are driving the decline of endangered southern dunlins (Calidris alpina schinzii). These genetic factors negatively impact breeding success and survival, highlighting their critical role in population persistence.
Area of Science:
- Conservation Biology
- Population Genetics
- Avian Ecology
Background:
- Small populations face increased extinction risk due to inbreeding and loss of genetic diversity.
- Empirical evidence from natural populations is limited.
- Southern dunlins (Calidris alpina schinzii) represent an endangered shorebird metapopulation experiencing decline.
Purpose of the Study:
- To investigate the role of genetic effects in the decline of the southern dunlin metapopulation.
- To combine long-term population data, fitness data, and molecular markers.
- To assess the impact of inbreeding and genetic diversity on population viability.
Main Methods:
- Long-term monitoring of population dynamics and individual fitness.
- Analysis of molecular markers (e.g., microsatellites, SNPs) to assess genetic diversity and relatedness.
- Field observations of parentage and mating patterns.
Main Results:
- Population decline is linked to increased mating between related individuals, including close inbreeding.
- Reduced genetic diversity negatively affects individual fitness across multiple life stages.
- Higher genetic similarity between mates correlates with lower hatching success and increased offspring mortality.
Conclusions:
- Genetic factors play a significant role in the rapid decline of the southern dunlin population.
- Inbreeding and loss of genetic diversity are critical threats to the persistence of small, endangered populations.
- Conservation strategies must consider genetic management for vulnerable species.
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