WSP04463

• File Number: 8460.500
• Description: Platte River Recovery Plan
• Basin: South Platte
• Date: 6/1/1997
• Author: Colo Div of Wildlife
• Title: Inventory and Status of South Platte River Native Fishes in Colorado
• Water Supply Pro - Doc Type: Publication

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bigmouth shiner ranged in relative abundance from 1.5 to 6.5 percent. All of these species were
found at over 50 percent of the sampling sites with the exceptions of big mouth shiners and
mosquitofish. Black crappies, longnose suckers, yellow perch, and green sunfish followed in
abundance (roughly 0.5% each of the total sample). It is interesting to note that their frequency
of occurrence among the sites (21-57%) was much higher than their relative abundance (0.48-
0.78%). Creek chub, johnny darter, brook stickleback, Iowa darter, white crappie, channel catfish
and bluegill were all found in small numbers. Over 14 percent of the fish sampled were
introduced species, while less than 3 percent were either uncommon or sensitive native species.
Overall, species composition and relative abundance suggest a degraded habitat.

The furthest downstream reach of the mainstem river in this hydrounit flows from the
confluence with the Big Thompson River near Greeley to a point near Fort Morgan. Seven sites
were sampled a total of nine times (Table 8). Again, only three species, fathead minnow, plains
killifish, and white sucker, comprised over 78 percent of the total sample (Table 9). By adding
creek chub and sand shiner, the percentage of this total reaches 92 percent. However, this species
composition is somewhat different from that observed in the upstream section. Sampling
conditions were very difficult in this reach and considered to be worse than conditions found in
the Henderson to Greeley reach. Red shiner, bigmouth shiner, and carp were the only other
common species seen (1.5-3% of the total). Brook stickleback, longnose sucker, green sunfish,
johnny darter, largemouth bass, white crappie, and hybrid striped bass were found in trace
numbers, and at only one site each.

The sampling crews failed to locate any water in any of the stream courses in the eastern
plains tributary portion of this hydrounit (Table 10). The tributaries which drain this portion when
water is present are Horse Creek, Lost Creek, Box Elder Creek, Sanborn Draw, Greasewood
Draw, and Long Draw. Although they did not document all dry locations, the sampling crew
reported searching the area extensively and locating no water. This area was sampled in 1988 and
provided much of the same results with three exceptions. One site on Boxelder Creek was found
to contain plains killifish, fathead minnows, Iowa darters, green sunfish, and carp, in that order of
abundance. Another site downstream of Horse Creek Reservoir which was dry in 1994,
contained water in 1988, and supported Iowa darters and plains killifish. Finally, a small reach of
Lost Creek contained abundant fathead minnows in 1988.

The obvious limiting factor in the eastern plains tributaries is lack of permanent water.
Analysis offish distribution in 1988 noted limited distribution offish species throughout eastern
plains tributaries to the South Platte River (Kehmeier and VanBuren 1990, unpublished). They
felt the single overriding variable was water availability. Obviously, the available habitat had
decreased in 1994 from what little there was in 1988. However, the extremely wet spring of 1995
may have led to re-colonization of some of these dry stream courses. The potential for
management through habitat manipulation (pool deepening and water manipulation) and artificial
re-colonization is high throughout the eastern plains.

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