8265

• UCREFRP Catalog Number: 8265
• Author: Allendorf and e. al.
• Title: RE
• USFW Year: 1994.
• USFW - Doc Type: Etter Pond Razorback Sucker Genetics Report.
• Copyright Material: NO

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ILLINOIS NATURAL HISTORY SURVEY
MEMORANDUM
CENTER FOR AQUA TIC ECOLOGY

..' .

TO:
FROM:
RE:
DATE:

Mike Stempel
Genetics Panel (Allendorf, Echelle, Philipp, Williamson)
Etter Pond Razorback Sucker Genetics Report

February 25, 1994

This memo should serve as the final review of the Genetics Panel on the Etter Pond
Razorback Sucker Report submitted by Dr. Don Buth. This review has been circulated and
edited by all members of the panel, representing consensus opinion. We believe that it would be
most useful and beneficial for this report to be circulated to Dr. Buth and other researchers
working on related projects (e.g., Drs. Dowling, Marsh, Douglas, Minckley, Morizot, Starnes)
for comment and discussion. We would be happy to answer any questions regarding what
follows.
As w.e reported at the Biology Committee Meeting in Salt Lake City (January 12-
14), we reviewed the report and do not agree with Dr. Buth's conclusion (p. 3 in bold) that "...the
entire Etter Pond population is introgressed with alleles from hybridization with flannelmouth
suckers." We disagree, therefore, with his recommendation that, "...all Etter Pond specimens,
and hatchery progeny, be destroyed to prevent the perpetuation and enhancement of genomic
pollution of the greater razorback population." Our arguments follow.

First, Dr. Buth's evidence for hybridization, suggested on page 3 as likely the result
of one or more F2 x F2 crosses, is based upon his classification of certain alleles (designated R
and F) as diagnostic for the two different species; i.e., that in "pure" populations, individuals are
fixed for their specific allele. This conclusion is based on a small survey of only a few
populations of flannelmouth and razorback suckers (Buth et. al., 1987). The three razorback
populations from which datil are presented (Lake Mohave, Senator Wash, and Dexter Hatchery)
most likely represent samples from a single gene pool from the lower basin. Recognition of
diagnostic alleles would require analyses of razorback suckers from populations in each of the
major drainages across the extant range of the species. In the 1987 paper, Buth et. al. report
fixed differences at only two loci, s-Sod-A2 and G6pi-A2; unfortunately, these loci were not
analyzed during the Etter Pond study. Two other loci analyzed in the 1987 study, CK-A and m-
Icdh-A, were used, however, neither of these loci showed fixed allelic differences between the
two species in the 1987 study. Buth et. al. (1987) attributed that allelic sharing to some level of
hybridization and implied that it represents a reasonably recent event. Two other loci, mMdh-A 1
and Ada-A2, were also included in the current analysis and listed as fixed markers. Because no
data on the allele distributions at these two new loci across razorback and flannelmomh
populations were provided, evidence for fixation cannot be evaluated. _