3505

• UCREFRP Catalog Number: 3505
• Author: Rinne, J., et al., ed. 1986.
• Title: American Fisheries Society,
• USFW Year: Role o
• USFW - Doc Type: \
• Copyright Material: YES

278

FISH CULTURE IN FISHERIES MANAGEMENT

uate these species, but will lead to down-listing or
de-listing through establishment of additional vi-
able population~..

Th'e Hatchery Role in Recovery of Cui-ui

Pyramid Lake, Nevada, has the greatest depth
and volume of any endorheic lake basin in the
Western Hemisphere. This Pleistocene remnant
is 25 miles in length, ranges from 4 to 10 miles in
width, and has maximum and mean depths of 338
and 164 ft, respectively (Galat et aI1981). It is a
nutrient-rich lake and once supported the largest
trout in the world, the Lahontan cutthroat (Salmo
clarki Irenshawi). The cui-ui (Clrasmistes cujus),
an endangered lacustrine sucker, is endemic to
Pyramid Lake. Because both congeners (c. bre-
virostris and C. liorus) are probably no longer
genetically pure, the cui-ui is very likely the only
surviving representative of the genus. The cui-ui
was of great historic importance in the Pyramid
Lake Paiute Indian culture and diet. The ancestral
name of the tribe is "Ky-yu-wi-kut-teh," meaning
"Cui-ui eaters." In 1967, because of decline of
the species, fishing for cui-ui by non-tribalmem-
bers was prohibited. The Tribal Council closed
fishing for the species by tribal members in 1979.
The predominant source of water for the lake
is the Truckee River, which flows 120 miles in a
northwesterly direction from Lake Tahoe. Major
diversions of the Truckce began in 1905 as a result
of the federally-funded Newland Reclamation Ag-
ricultural Project. Diversions have resulted in a
75-ft loss in the elevation of Pyramid Lake since
that time. This water-level decline caused for-
mation of a delta at the mouth, which made it
progressively more difficult for cui-ui and cutthroat
trout to spawn in the river. By 1938, the famed
Pyramid Lake cutthroat trout was considered ex-
tinct. The cui-ui was greatly reduced in number
by that time (Koch 1973) and probably survived,
in part, because of their longevity (28 + years,
vide Sigler and Kennedy 1978). Also important is
their relatively short egg-incubation period, which
permitted limited successful spawning in the Truckee
River delta region and in a few other small tri-
butaries.
Present restoration efforts for the cui-ui include
spawning habitat rehabilitation, maintenance of
water quality in the Truckee River, maintenance
of lake level, fishway and ladder construction, and
artificial propagation.

Hatchery Operations

A Paiute tribal hatchery has been in~peration. .
since 1973. Cui-ui culture techniques' were~ pi~,'
oneered by Koch (1972) and Koch andCo~treras,,'n
(1973). The first facility was located on Hard-
scrabble Creek, a seasonal stl"eam on the west
shore of Pyramid Lake. This initial operation was
plagued by difficulties related to both qu~l~ty ~d
quantity of water. Two sourc~s were utl~lzed an
this facility: (1) a well that proVided approximately
1.25 gal of iron-bacteria contaminated wa~er, a~d
(2) Hardscrabble Creek, which was unrel~able an
permanency and temperature. Despite?vera.1l
failure, valuable experience was gaane~ 10 thiS
operation. . .
Mature cui-uis were netted from the delta region
of the lake and transported to a dirt holding pond
or trough at the hatchery site. Fish were then
stripped, and eggs incubated in standard egg jars.
Eggs hatched in about 5 days, and 0.3-inc~ la~ae
were transferred to fiberglass troughs unttJ sWim-
up. During the incubation period, severe egg
mortalities were experienced that were attributed
to infestations of fungus (Saprolegnia sp.). '
Early propagational problems made it apparent
that any rearing facility would require a consistent
source of high quality water and the flexibility to
permit modification of hatchery techniques to
refine methods further. Construction of a closed-
system cui-ui rearing facility was initiated. Until
completion of this facility, artificial propagation
activities were moved to the closed-system Dunn
Trout llatchery in 1978. This temporary operation
experienced numerous problems until the new
hatchery became operational i'l197f}. The hatchery
was completed immediately prior to the 1979 cui-
ui spawning run, when little time was available
for organizing activities. Numerous problems, in-
cluding gas supersaturation, elevated water tem-
perature. and severe fungus infestations,' occurred
during the first year. These experiences further
served to introduce culturists of the species to the
I , ,
subtleties of hatching and rearing this endange~ed
fish.

Preselll Facilities

,The current cui-ui rearing facility is a closed
system having biological filtration and ultraviolet
sterilization. It includes a back-up diesel generator
and automatic transfer switch to protect eggs and
larvae from frequent power outages,~mmon to
this remote area. Other major~h~g~ . .
::<~"'ltn . ')$;1;,.' '"',