Importance. The Yampa River is the largest remaining essentially unregulated river in the Upper Colorado River Basin, and its inflow into the Green River, 65 miles downstream of Flaming Gorge Dam, ameliorates some effects of dam operation on river flow, sediment load, and temperature (Xxxx et al. 2000). Holden (1980) concluded that flows from the Yampa River, especially spring peak flows, were crucial to the maintenance of the Green River’s “large-river” characteristics and, therefore, very important to maintaining suitable conditions in the Green River downstream of the confluence. The Yampa River supports resident subadult and adult Colorado pikeminnow, contains one of the primary Colorado pikeminnow spawning areas in the Upper Basin and is a major producer of fish for the entire Green River subbasin (Xxxx and Xxxx 1989). A small population of humpback chub exists in the Yampa River in Dinosaur National Monument (Xxxx and Xxxx 1989; U.S. Fish and Wildlife Service 1990a, 2002a). Spawning aggregations of adult razorback sucker were observed near the mouth of the Yampa River, and adult razorback sucker were captured upstream to the mouth of the Little Snake River (Xxxx and Xxxx 1989). The lower portion of the Yampa River was part of the historic range of bonytail and is associated with some of the most recent captures of this very rare fish. The Bonytail Recovery Plan (U.S. Fish and Wildlife Service 1990b) identified the Yampa River within Dinosaur National Monument as a high priority recovery and/or restoration site. The Little Snake River provides approximately 28% of the Yampa River's flow and 60% of the Yampa River’s sediment supply. The sediment supply of the Little Snake River is believed to be important to the maintenance of backwater nursery areas utilized by young Colorado pikeminnow in the Green River (Xxxxx and Green 1991). Adult Colorado pikeminnow have been captured in the Little Snake River upstream to near Baggs, Wyoming, and humpback chub have been captured in the lower 10 miles of the Little Snake River (U.S. Fish and Wildlife Service 2002a, 2002c).
Importance. The Xxxxxxx River is historic habitat for Colorado pikeminnow; both adult and young-of- the-year fish were captured in the 1950's and 1960's. Xxxxxx et al. (1991) documented the use of the lower 1 mile of river by Colorado pikeminnow. Uranium processing facilities operated during the late 1940's through the 1960's severely impacted the river and may have contributed to the decline of Colorado pikeminnow in the Xxxxxxx River drainage. Since 1996, bonytail have been stocked in the Colorado River near the confluence of the Xxxxxxx.
Importance. Colorado pikeminnow and razorback sucker regularly utilize the mouth of the Duchesne River especially during spring runoff. Fishery surveys conducted in 1993 documented the use of the lower 15 miles of the Duchesne River by Colorado pikeminnow and razorback sucker. More recently, fish surveys have been conducted in the lower 33 miles of the Duchesne River and have documented seasonal use by Colorado pikeminnow and razorback sucker.
Importance. The Gunnison River is currently occupied by wild Colorado pikeminnow and is historic habitat for razorback sucker and presumably bonytail. Several adult Colorado pikeminnow were captured in the Gunnison River in fishery surveys conducted in 1992 and 1993. Unrestricted migration of fish has been limited by the 10-foot high Redlands diversion dam located 2 miles upstream from the mouth of the Gunnison River. Several Colorado pikeminnow larvae have been collected in the Gunnison River upstream and downstream of the Redlands diversion dam. Xxxx (1977) reported that adult razorback sucker were collected frequently by commercial fishermen near Delta, Colorado, between 1930 and 1950. Razorback sucker larvae were recently collected in the Gunnison River (Osmundson and Seal 2009), and the reach near Delta is considered a priority razorback sucker restoration site. The native fish assemblage in the Gunnison River is presently less impacted, compared to other rivers, by nonnative fishes (particularly piscivorous species), and management efforts should emphasize preserving this feature of the river.
Importance. The Green River system supports populations of humpback chub and Colorado pikeminnow, and it historically supported populations of bonytail and razorback sucker. The importance of the Green River to the endangered fishes has been established by the Recovery Program and recognized by many biologists. The Colorado Squawfish [Pikeminnow] Recovery Plan (U.S. Fish and Wildlife Service 1991) listed the Green River as the highest priority area for recovery of the species, and the recovery goals (U.S. Fish and Wildlife Service 2002c) consider the Green River subbasin as the center of the Upper Basin Colorado pikeminnow metapopulation. Habitat in Desolation and Gray canyons supports a self-sustaining humpback chub population, and the last known riverine concentration of wild bonytail was in the Green River within Dinosaur National Monument (U.S. Fish and Wildlife Service 1990a, 1990b, 2002a, 2002b). Recovery plans for humpback chub (U.S. Fish and Wildlife Service 1990a) and bonytail (U.S. Fish and Wildlife Service 1990b) identified the Green River in Desolation and Gray canyons and in Dinosaur National Monument as important to recovery. Until recently, the Green River supported the last known riverine concentration of wild razorback sucker (Xxxxxxx and Xxxx 1989; U.S. Fish and Wildlife Service 1998, 2002d).
Importance. The Minneapolis Public Schools (MPS) along with the Minneapolis Federation of Teachers (MFT) agree on the importance of professional development and support of its teachers. It is a crucial factor in creating and maintaining an excellent school system focused on ensuring that all students learn. In addition, the District's ability to attract, develop, and retain excellent and diverse teachers is improved when a strong professional development foundation exists.
Importance. Adult Colorado pikeminnow occupy the White River downstream of Xxxxxx Draw Dam near Rangely, Colorado, in relatively high numbers. Adult Colorado pikeminnow resident to the White River spawn in the Green and Yampa rivers. Juvenile and subadult Colorado pikeminnow also utilize the White River on a year-round basis. Incidental captures of razorback sucker have been recorded in the lower White River. Construction of Xxxxxx Draw Dam in 1984 blocked Colorado pikeminnow migration to upper portions of the White River.
Importance. The Gunnison River is currently occupied by wild Colorado pikeminnow and is historic habitat for razorback sucker and bonytail. Several adult Colorado pikeminnow were captured in the Gunnison River in fishery surveys conducted in 1992 and 1993. Unrestricted migration of fish has been limited by the 10-foot high Redlands diversion dam located 2 miles upstream from the mouth of the Gunnison River. Several Colorado pikeminnow larvae have been collected in the Gunnison River upstream and downstream of the Redlands diversion dam. Xxxx (1977) reported that adult razorback sucker were collected frequently by commercial fishermen near Delta, Colorado, between 1930 and 1950. Wild razorback sucker have not been collected in the Gunnison River in recent times, although the reach near Delta is considered a priority razorback sucker restoration site.
Importance. The mainstem Colorado River from Rifle, Colorado, to Lake Xxxxxx, Utah, supports populations of humpback chub and Colorado pikeminnow, and is recognized as important to the recovery of all four endangered fishes (U.S. Fish and Wildlife Service 1990a, 1990b, 1991, 1998, 2002a, 2002b, 2002c, 2002d). Relatively large and healthy humpback chub populations occur at Black Rocks and Westwater Canyon near the Utah-Colorado state line. A smaller humpback chub population occurs in Cataract Canyon, and some of the last wild bonytail were collected in this river reach. All life stages of Colorado pikeminnow occur in the section of river from Palisade, Colorado, downstream to Lake Xxxxxx. Colorado pikeminnow have been translocated and stocked into the upper reach of the Colorado River between Palisade and Rifle, Colorado; natural access to this historic-habitat reach has been blocked since the early 1900's by three diversion dams near Palisade. Razorback sucker populations in the mainstem Colorado River have declined precipitously in the past 20 years. In 1993, 67 adult razorback sucker were collected from isolated ponds adjacent to the Colorado River near Debeque, Colorado. Since then, only a few wild adult razorback sucker have been captured from the river, and there is no evidence of successful reproduction in the Colorado River.
Importance. The mainstem Colorado River from Rifle, Colorado, to Lake Xxxxxx, Utah, supports populations of humpback chub, razorback sucker, and Colorado pikeminnow, and is recognized as important to the recovery of all four endangered fishes (U.S. Fish and Wildlife Service 1990a, 1990b, 1991, 1998, 2002a, 2002b, 2002c, 2002d). Relatively dense populations of humpback chub occur at Black Rocks and Westwater canyons near the Utah-Colorado state line. Both populations experienced a decline around the year 2000 and remained low for over a decade (Xxxxxxx 2012; Xxxxxxx and XxXxx 2011). Populations in both Black Rocks and Westwater stabilized in 2011-2012 and preliminary estimates from sampling in 2016-2017 show signs of population increases (Xxxxxxx et al. 2016, Xxxxx et al. 2016, X. Xxxxxxx and X. Xxxxx, unpublished data). Population estimates resumed in 2020 in Westwater Canyon and will resume in Black Rocks in 2021. A small but persistent humpback chub population occurs in Cataract Canyon where some of the last wild bonytail in the Colorado River were collected. All life stages of Colorado pikeminnow occur in the section of river from Palisade, Colorado, downstream to Lake Xxxxxx. Numbers of adult Colorado pikeminnow fluctuated around 600 fish from 1992 to 2008 (Osmundson and White 2009), but have declined since. The most recent population estimates (collected in 2013 - 2015) indicate the adult population has declined to about 400 individuals, among the lowest estimates on record (Xxxxxxx et al. 2020). Researchers reported strong numbers of subadults and record high catch of age-0 Colorado pikeminnow in 2015. Age-0 catch rates were strong in 2016 and 2018, but were dramatically lower in 2017. Since 2008, with the completion of the Price-Stubb fish passage structure, the endangered fish have regained access to historically occupied reaches of the Colorado River upstream of Palisade, Colorado. Wild razorback sucker populations in the mainstem Colorado River declined precipitously in the early years of the Recovery Program, but stocked individuals have been accumulating over the past decade, with around 8,000 adults estimated in 2015 (Xxxxxxx et al. 2020). Wild-produced age 1+ and 2+ juveniles were collected in the lower Colorado River in 2013, and wild age-0 fish were collected in 2018. Bonytail are stocked in the Colorado River according to the revised Integrated Stocking Plan (Integrated Stocking Plan Revision Committee 2015), but similar to other upper basin locations...
