[acn-l] recent conservation trip to NV

peter.unmack at ASU.Edu
Sat, 02 May 1998 11:53:41 -0700 (MST)

G'day folks

March 19-22 saw a successful conservation trip to the southeastern portion
of Nevada. Members from several conservation orientated clubs
participated in this event including the Bay Area Killifish Association,
North American Native Fishes Association, Northern California Killifish
Club, and Tropical FishKeepers Exchange. A great fun filled weekend was
had by all. Our first effort was concentrated on the Moapa River near
Glendale. Tilapia (Oreochromis aureus) had recently invaded parts of the
upper springhead near the Fish and Wildlife Service Refuge. Great gobs of
tilapia were found throughout the spring outflow along with a good numbers
of mollies (Poecilia mexicana) and damnbusia (Gambusia affinis). A few
native springfish (Crenichthys baileyi moapae) and Moapa dace (Moapa
coriacea) were also seen but they were far rarer than the section without
tilapia. Further downstream near the old powerstation diversion dam fish
were virtually non existent. Electrofishing revealed virtually no fish
except a couple of exotics. Gill nets were set overnight in the ponds
down at the power plant. Last year Jim Heinrich (Nevada Division of
Wildlife) caught good numbers of Virgin River chubs (Gila seminuda) here.
The only fishes caught by us were more great gobs of tilapia (some up to
~16 inches) and a few baby mollies were observed. The Moapa is indeed a
pretty sick system at this point in time.

Our second destination was the Virgin River at Mesquite. Both woundfin
(Plagopterus argentissimus) and Virgin River chubs have been released here
from hatchery stocks here. The fish have small metal tags which allow
them to be distinguished from wild fish. Good numbers of most native fish
were found including speckled dace (Rhinichthys osculus), flannelmouth
sucker (Catostomus latipinnis), and desert sucker (Pantosteus clarki) as
well as the two stocked natives. Red shiners (Cyprinella lutrensis) were
present, but in lower numbers than usual. While the riverine environment
looked to be in really healthy shape it doesn't last very long. According
to Jim Heinrich, water diversions during summer virtually dry this stretch
of river leaving the fish little suitable habitat and elevated water
temperatures. We moved upstream into Arizona to the mouth of Beaver Dam
Wash primarily to collect desert suckers for genetic work by Carol Secor,
a graduate student at Arizona State University. Fortunately good numbers
of suckers were found along with hundreds of speckled dace! That evening
saw us camp further upstream in Beaver Dam Wash at a delightful
campground. Here we were finally able to see some Virgin River spinedace
(Lepidomeda mollispinis), the rarest native fish in this drainage.

All in all a great time was had by all participants. I'd like to thank
all those who made the effort to come along and help. Special thanks go
to Ellen Siegal who did a fantastic job feeding the group. Also, thanks
again to Jim Heinrich for allowing us the opportunity to get involved and
for making arrangements. All collecting in Nevada was done under his
supervision, collecting in Arizona was conducted under state and federal

Our next major trip will be to Ash Meadows and _should_ be over the
Columbus day weekend (October 9-12). More details will be made available
shortly. We may also have a smaller trip in early September although
details of this trip won't be known for some time. Please feel free to
contact me regarding any of the above. Anyone and everyone is welcome!

Best Fishes

Peter J Unmack peter.unmack at asu.edu
DESERT FISHES RULE: To boldly thrive where no other fish can make it!

Australian desert fishes pages at http://ozdesertfish.base.org (don't
forget to visit the Desert Fishes Council pages too)
Native Fish Australia pages at http://www.nativefish.asn.au
North American Native Fishes Association at http://www.nanfa.org
Aquatic Conservation Network at http://www.acn.ca