Difference between revisions of "FISH"

• AZ Daily News_ Razorback Sucker turns up in Grand Canyon after 20 years
  • The last one recorded had been caught in 1990.
  • Caught October 9th, lower part of Grand Canyon believed to have traveled upstream some 50 miles from Lake Mead.
• Whirling Disease Page

Quick Facts

• Diet studies of Rainbow Trout and Brown Trout in Grand Canyon indicate that these species do eat native fish.
• Rainbow Trout are less piscivorous than Brown Trout, but there are more RBT than BRT
  • "Brown Trout consumption rate 20 times that of Rainbow Trout..." (MYard)
• Rainbow and Brown Trout disporpotionately prey on native fish
• Warming increases the growth rates of Humpback Chubs
• 75% of the fish species were endemic to the Colorado River basin; this is the highest degreee of endemism of any large river basin in North America. (SDM Workshop Aug 2013)

Work in progress

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• RValdez_Talus shoreline habitat used by HBC

• • Fish
• What type of fish are found in Lake Powell?
• 1.Endangered

◦Four types of fish that frequent the Colorado River and Lake Powell are officially endangered because of the construction of dams and introduction of non-native species: the razorback sucker, Colorado pikeminnow, humpback chub and bonytail. Native ◦In addition to the above, Lake Powell is naturally home to the bluehead sucker, flannelmouth sucker, roundtail chub and speckled dace. ◦Non-Native Bass ◦The National Park Service introduced three types of bass specifically for fishing purposes: the smallmouth bass, largemouth bass and striped bass. Other Non-Natives For Fishing ◦Other non-native species have been introduced into Lake Powell with the intent of challenging fisherman. These include walleye, rainbow trout, channel catfish, bluegill and black crappie. Problematic Non-Native ◦Though almost all non-natives are damaging to native ecosystems, the gizzard shad is causing many problems to the native and non-native fish populations because of its large size. The fish has spread throughout the lake and have no natural predators.

• Humpback Chub Page
• Razerback Sucker Page
• Bonytail Page
• Lees Ferry Sport Fishery Page
• GCDAMP POAHG- Historical Native Fishes of Glen and Grand Canyon

2015

• Native and Nonnative Interactions; Factors Influencing Predation and Competition

• NPS Fish Species found in the Grand Canyon
• NPS Grand Canyon Vertebrate Species List
• NPS Grand Canyon Treatened & Endangered Species List
• NPS Endangered Fish Learning
• "NNFC will occur if necessary because it is a conservation measure required under the ESA to ensure protection of the HBC."
• Mitigation for the impact of implementing NNFC on resources of tribal concern is addressed under the NHPA OA for NNFC.
• The (HBC) juvenile abundance estimate for the mainstem at the LCR is over 2,500 fish, and is above the conservation measure trigger for nonnative fish control in the FWS biological opinion of 900.130220 AMWG Minutes