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

remaining area located either in transition zones or on the plains. For this investigation,
approximately 462 square miles of Hydro unit 10190002 provided suitable habitat for plains fishes
surveys.

Most of the sampling took place in the West Plum Creek drainage as this area historica1ly
contained Colorado fish species of special concern. The habitat in West Plum Creek and its
tributaries is comprised of relatively unimpacted transition zone stream courses with healthy
riparian habitat. The substrates vary and range from silt to cobble. Land use has been primarily
horse ranching and light grazing, with minimal irrigated cropland. West Plum Creek faIls entirely
in Douglas County, which has experienced dramatic urban-residential growth and development in
the last five years.

Of the 55 sites investigated in the plains portio!) of Hydro unit 10190002,48 sites
contained fish and seven sites yielded no fish (Table 3). No dry sites were encountered in
Hydrounit 10190002. The seven lentic sites lacking fish were constructed ponds within Chatfield
State Park and were surveyed for water quality and physical habitat parameters. These ponds
may serve as refugia management sites for rare species as a1l are individually regulated with
headgates and drains.

A total of 9062 fish were sampled within Hyd~ounit 10190002, comprising 21 species of
which 15 are native and 6 introduced (Table 4). Four: special concern species were co1lected,
including plains topminnow, Iowa darter, common shiner, and northern redbe1ly dace. Northern
redbe1ly dace were co1lected only in the West Plum Creek sub drainage. Fathead minnow and
creek chub comprised 56 percent of the total, and occurred at 44 and 60 percent of the sites
sampled, respectively. Longnose dace was the third most abundant species with 1382 individuals
coIlected. The five species in the abundant category made up 75 percent of the sample. The
common group, comprised of big mouth shiner, Iowa ;darter, longnose sucker, green sunfish,
brook stickleback, stonero1ler, johnny darter and plai~s topminnow, made up 20 percent of the
total. Northern redbe1ly dace and common shiner (both in the uncommon category) comprised
roughly 3 percent of the total drainage catch. Six introduced species (largemouth bass, goldfish,
yeIlow perch, brook, rainbow and brown trout) accounted for the remaining 2 percent (Table 4).
AIl species except brown trout were co1lected with multiple sizes present at one site or another.

Iowa darter were co1lected from four lentic and six lotic habitats. Multiple sizes ofIowa
darter were observed at 6 of the 10 sites. Plains topminnow were co1lected from lentic habitab
only--primarily marshy ponds with silt substrates an~ aquatic vegetation, and a1l contained
filamentous algae. Multiple sizes of plains topminnow were coIlected at all sites. The majority of
northern redbeIly dace were found in two ponds, while one individual was coIlected from each of
two stream sites: West Plum Creek above Garber Creek, and Jackson Creek below Jackson Creek
Road. Multiple sizes of northern redbe1ly dace were co1lected only at West Garber Pond; all other
sites were occupied by adults only. Common shiner were sampled from two ponds (Kost Pond
and Pine Cliff Pond), and three stream sites (two of which were exclusively pool habitats).
Multiple sizes of common shiner were found in West Plum Creek below Red Rock Road and in a

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