7362

• UCREFRP Catalog Number: 7362
• Author: Karp, C. A. and H. M. Tyus.
• Title: Habitat Use, Spawning, and Species Associations of Humpback Chub,
• USFW Year: 1989.
• Copyright Material: NO

collected in Split Mountain Canyon. As with humpback chubs, roundtail
chubs were most abundant (N=1,085, 73%) in the upper 44.8 km of Yampa
Canyon. Mature roundtail chub were most often captured in shoreline runs
and riffles but were also taken in eddies and pools. Roundtail chubs in
breeding condition (N=240; including 116 males, 5 females, and 119
tuberculate but unripe fish) were more darkly colored than humpback chub
and exhibited a more robust tuberculation and more brilliant orange
coloration. Patterns of tuberculation were similar between the two chubs.
Ripe male roundtail chubs averaged 344 mm TL (N=116, range 292-419 mm TL)
and 329 g (N=100, range 190-652 g) and ripe females averaged 360 mm TL
(N=5; range 343-380 mm TL) and 363 g (N=3, range 276-478 g). Tuberculate
but unripe fish averaged 351 mm TL (N=119; range 264-447 mm TL) and
weighed about 364 g (N=77, range 140-844 g).
As with humpback chub, ripe roundtail chub were also collected during
declining spring runoff following peak flows (Figure 2). Roundtail and
humpback chub in breeding condition were collected syntopically on 13
occasions. Although this suggested some overlap in use of shoreline eddies
during spring runoff, ripe females of both species were never syntopic.
Channel catfish and the common carp were the most abundant
introduced fishes captured in DNM (Table 2). A total of 1,153 juvenile and
adult channel catfish and 1,321 common carp were captured in shoreline
eddies, pools, runs, and riffles during spring runoff, 1987 to 1989.
Although most fish were captured in Yampa Canyon (channel catfish: N=853,
74%; common carp: N=865, 65%), catch-per-unit-effort data indicated both
species were most abundant in Split Mountain Canyon (Table 2). More
channel catfish were captured angling than any other fish species,.and it
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