Green River Watershed Native Non-Game Fish Species Research: Phase II
Author(s):Publication Date: 2004-06
Tags: Green River, WLCI, WLCI Agency Report
Currently, little is known about the native fish assemblages present in the Green
River drainage of southwestern Wyoming. Of particular interest are the bluehead sucker
(BHS), flannelmouth sucker (FMS), and the roundtail chub (RTC).
Bluehead sucker, FMS, and RTC have declined in Wyoming and throughout their
native ranges. The Natural Heritage Program assigns BHS the global ranking of G4
suggesting its existence to be abundant and globally secure, although it may be quite rare
in parts of its range and is thus the element of long-term concern (Fertig and Beauvais
1999). The Natural Heritage Program assigns FMS the global ranking of G3/G4
suggesting its existence to be uncertain. It is uncommon but seems to be locally secure.
The Natural Heritage Program assigns the RTC the global ranking of G3 suggesting its
existence to be very rare throughout its range or locally abundant but highly restricted.
The BHS is classified by the Wyoming Game and Fish Department (WGFD) as
an NSS1 species, indicating that it is rare and its habitat is declining or vulnerable. The
FMS and RTC are classified by the WGFD as NSS2 species indicating that they are rare,
but their habitat is stable. Surveys conducted by Baxter (Baxter and Simon 1970) and
Wheeler (1997) represent the only drainage-wide efforts conducted in the Green River
drainage of Wyoming. The most recent surveys conducted by Wheeler (1997) showed
that between 1965 and 1995 all three species had declined at three spatial scales (site,
stream, and sub-drainage) in the Green River drainage of Wyoming. He did not find
BHS in the Green River drainage in 1995, and only found RTC in the Blacks Fork
drainage. Flannelmouth sucker were documented throughout the Green River drainage in
1995, but were not collected in the Little Snake River drainage (Wheeler 1997).
Additional sub-drainage surveys have been conducted in the Bitter Creek drainage
(Carter and Hubert 1995) and in the Big Sandy River drainage (Miller 1978). Bluehead
sucker and RTC were not collected in the 1993 Bitter Creek survey, but FMS were
collected from a site near the Bitter Creek-Green River confluence (Carter and Hubert
1995). Miller (1978) reported on a survey of the entire Big Sandy River drainage in the
1960s and ‘70s. They found RTC and BHS at one site each in the Big Sandy River
upstream of Big Sandy Reservoir. They also collected BHS at one site on Little Sandy
Creek. Flannelmouth sucker were found to occur throughout the Big Sandy River and
Little Sandy Creek below the National Forest boundary.