WSP04079

• File Number: 8240.200.40.J
• Description: Yampa
• State: CO
• Basin: Yampa/White
• Water Division: 6
• Date: 7/1/1989
• Title: Habitat Use and Streamflow Needs of Rare and Endangered Fishes, Yampa River, Colorado
• Water Supply Pro - Doc Type: Publication

Table 6. Delineation of critical river reaches for rare and endangered Colorado River fishes in the Yampa River, with
notes on potential limiting factors.

Life history stage

Potential limiting factors

Adult
Concentration
Migration
Spawning
Larva
Juvenile

Adult
Concentration
Spawning
Larva
Juvenile

Adult

Adult
Spawning
Larva

Location (RK)"

Season

Colorado Squawf'lSh

occupied habitat in the White River due to blockage of
access to overwintering areas (Martinez 1986).
Localized water input at the spawning grounds may
provide orientation cues for spawning Colorado
squawfish, and thus, significance of groundwater and
surface inflows in these areas, relative to survival of
endangered fishes, should be further investigated.
The reproductive success of Colorado squawfish
depends on a number of interdependent factors,
including the number of spawning adults (particularly
ripe females), river discharge, sediment load,
temperature, and photoperiod. Condition and
physiological readiness are also important factors. The
presence of adult Colorado squawfish in inundated

0-224
82-198
0-224
6-51
0-50
0-224

All year
August-May
May-August
June-August
July-August
All year

Spring peak flows; overbank flooding:
seeps in spawning reaches; number
of ripe females; angling or other
incidental takes; siltation of
spawning substrate; competition and
predation with nonnative fishes;
food availability; stream blockage:
low flows late summer, fall, and
winter; stability of winter flows.

Humpback Chub

0-90
6-64
19-64
0-64
0-90

All year
All year
May-July
May-July
All year

Spring peak flows; availability of
shoreline eddy habitat and deep
canyon habitat; competition and
predation by nonnative fishes.

0-16

All year

Bonytail Cbub

Factors unlcnown.

Razorback Sucker

Spring peak flows; overbank flooding:
number of reproducing adults;
competition and predation by non.
native fishes; lack of su bstantive
recruitment to juvenile life history
stage.

0-21
O-{j
O-{j

All year
April-June
April-June

a Numbers represent river kilometers (rounded) upstream from the mouth of the Yampa River.

shorelines and lowlands during spring runoff suggests
that such behavior, and associated feeding, may offset
the large energy expenditure required for migration and
spawning. Thus, natural overbank flooding in spring and
the consequent increased availability of floodplain
nutrients (Welcomme 1979) are important factors in
physiological readiness of Colorado squawfish. The loss
of successful reproduction in one or more years could
effect a further decline of Colorado squawftsh.
Colorado squawfish eggs are adhesive, and hatching
success may depend on their attachment to substrate
surfaces. Therefore, availability of cleaned cobble and
boulder surfaces in spawning areas may be limiting, if
flushing action from peak flows is significantly curtailed

19