Development of Species Diagnostic RFLP Markers for Cisco and Lake Whitefish

Session: 08a. - Restoration of Native Fishes

Ellen George, Cornell University, [email protected]
Matthew Hare, Cornell University, [email protected]
Lars Rudstam, Cornell University Bio Field Station, Dept. of Natural Resources, [email protected]

Abstract

Cisco Coregonus artedi were once an ecologically and commercially important species in the Great Lakes before their collapse in the early 1900s. Today, Lake Ontario contains only two established spawning populations in Chaumont Bay and the Bay of Quinte. In the last decade, research and restoration efforts have increased with much of the work focused on the Chaumont Bay spawning population. In addition to concerns about spawning habitat and quality, the Chaumont Bay population faces two potential genetic threats; a loss of genetic diversity following severe population reduction and hybridization and introgression with lake whitefish C. clupeaformis. To address these concerns, we developed a panel of species diagnostic nuclear markers to measure the rate of hybridization in the Chaumont Bay population. RNA was extracted from gill tissue from both species, and transcriptomes were sequenced and assembled using rainbow trout Oncorhynchus mykiss as a reference genome. We identified restriction fragment length polymorphisms (RFLPs) with strong frequency differences between the two species. Primers were designed for each locus and tested on known adult samples to create a diagnostic panel. This panel was then applied to a previous collection of visually identified larval samples to relate nuclear hybridity to morphology.

1. Keyword
genetics

2. Keyword
Lake Ontario

4. Additional Keyword
Coregonines