Conservation Genetics

, 4:659

Microsatellite variation in Bavarian populations of European grayling (Thymallus thymallus): Implications for conservation

  • Bernhard Gum
  • Riho Gross
  • Oswald Rottmann
  • Wolf Schröder
  • Ralph Kühn
Article

DOI: 10.1023/B:COGE.0000006106.64243.e6

Cite this article as:
Gum, B., Gross, R., Rottmann, O. et al. Conservation Genetics (2003) 4: 659. doi:10.1023/B:COGE.0000006106.64243.e6

Abstract

European grayling populations in Bavaria have shown steady declines during the last 10–20years. In order to provide guidelines for conservation strategies and future management programs, we investigated the genetic structure of 15 grayling populations originating from three major Central European drainages (the Danube, the Elbe and the Rhine/Main) using 20 microsatellite loci. Genetic divergence between the three drainage systems was substantial as illustrated by highly significant heterogeneity of genotype frequencies, high number of drainage-specific private alleles, high between-drainage FST values, high assignment success of individuals to their drainage of origin and the high bootstrap support for the genetic distance based drainage-specific population clusters. In agreement with earlier studies, microsatellites revealed relatively low levels of intrapopulational genetic diversity in comparison to the overall level of variation across populations. Maximum likelihood methods using the coalescent approach revealed that the proportion of common ancestors was generally high in native populations and that the estimates of Ne were correlated with the genetic diversity parameters in all drainages. The number of effective immigrants per generation (Nem) was less than one for all pairwise comparisons of populations within the drainages, indicating restricted interpopulational gene flow. Based on these findings we recommend a drainage and sub-drainage specific conservation of grayling populations in order to preserve their overall genetic diversity and integrity. For large-scale stocking actions to supplement declining or to restore extinct populations, creation of separate broodstocks for major conservation units (ESUs and MUs) is warranted.

assignment testconservation unitsgenetic differentiationmicrosatellitessalmonidsThymallus thymallus

Copyright information

© Kluwer Academic Publishers 2003

Authors and Affiliations

  • Bernhard Gum
    • 1
  • Riho Gross
    • 2
  • Oswald Rottmann
    • 3
  • Wolf Schröder
    • 1
  • Ralph Kühn
    • 1
  1. 1.Wildlife Biology and Management Unit, Department for Ecosystem and Landscape ManagementTechnical University Munich-WeihenstephanFreisingGermany
  2. 2.Institute of Animal Science, Estonian Agricultural UniversityTartuEstonia
  3. 3.Department for Animal SciencesTechnical University Munich-WeihenstephanFreisingGermany