thumbnail

Early detection of nonnative alleles in fish populations: When sample size actually matters

Fisheries

By:
https://doi.org/10.1080/03632415.2017.1259947

Links

Abstract

Reliable detection of nonnative alleles is crucial for the conservation of sensitive native fish populations at risk of introgression. Typically, nonnative alleles in a population are detected through the analysis of genetic markers in a sample of individuals. Here we show that common assumptions associated with such analyses yield substantial overestimates of the likelihood of detecting nonnative alleles. We present a revised equation to estimate the likelihood of detecting nonnative alleles in a population with a given level of admixture. The new equation incorporates the effects of the genotypic structure of the sampled population and shows that conventional methods overestimate the likelihood of detection, especially when nonnative or F-1 hybrid individuals are present. Under such circumstances—which are typical of early stages of introgression and therefore most important for conservation efforts—our results show that improved detection of nonnative alleles arises primarily from increasing the number of individuals sampled rather than increasing the number of genetic markers analyzed. Using the revised equation, we describe a new approach to determining the number of individuals to sample and the number of diagnostic markers to analyze when attempting to monitor the arrival of nonnative alleles in native populations.

Additional publication details

Publication type:
Article
Publication Subtype:
Journal Article
Title:
Early detection of nonnative alleles in fish populations: When sample size actually matters
Series title:
Fisheries
DOI:
10.1080/03632415.2017.1259947
Volume:
42
Issue:
1
Year Published:
2017
Language:
English
Publisher:
Informa UK Limited
Contributing office(s):
Northern Rocky Mountain Science Center
Description:
13 p.
First page:
44
Last page:
56