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<br />Table 7. Anecdotal accounts of native and non-native fishes in the Colorado River in Grand Canyon.
<br />
<br />Date
<br />
<br />Notes
<br />
<br />1962
<br />
<br />Expedition (Diarist)
<br />P. T. Reilly
<br />
<br />1963
<br />1963
<br />1964
<br />1965
<br />1965
<br />
<br />Reilly (1999, p. 445)
<br />Reilly (1999, p. 446)
<br />Reilly (1999, p. 446)
<br />Reilly (1999, p. 449)
<br />Reilly (1999, p. 450)
<br />
<br />He observed trout in Lava Creek and caught catfish at Elves Chasm. He caught rainbow trout at Spencer
<br />Canyon.
<br />28,800 trout, 7-9 in. long, and one million bass were planted at Lee's Ferry.
<br />89,080 "catchable" rainbow trout were released between the dam and Lee's Ferry.
<br />88,200 rainbow trout were released at Lee's Ferry; 10,000 were 10 in. long
<br />9,500 rainbow trout were released at Lee's Ferry in the first three months of 1965.
<br />Parasitic cysts first observed in trout at Lee's Ferry.
<br />
<br />recorded their presence in the 1950s. In 1937,
<br />Holmstrom repeatedly and humorously noted that
<br />"rats" ate his butter, indicating that consumption of
<br />unsecured food by rodents is not new in Grand Canyon.
<br />
<br />Fishes
<br />
<br />.
<br />
<br />Eight species of native fish were found in the
<br />Colorado River in the 19th century (Fig. 6). Although
<br />none of these species is extinct within the Colorado
<br />River basin, four species -- Colorado pikeminnow
<br />(Ptychocheilus Lucius), bony tail (Gila elegans),
<br />roundtail chub (Gila robusta), and razorback sucker
<br />(Xyrauchen texanus) -- have been extirpated from
<br />Grand Canyon (Minckley, 1991). The humpback chub
<br />(Gila cypha), flannelmouth sucker (Catostomus
<br />latipinnis), bluehead sucker (c. discobolus), and
<br />speckled dace (Rhinichthys osculus) all retain
<br />reproducing populations in Grand Canyon. Human
<br />modification of the riverine environment, and most
<br />notably the construction of Glen Canyon Dam and its
<br />regulated, cold-water releases, are generally blamed for
<br />declines in native species. Also, 24 species of non-
<br />native fishes have been introduced or escaped into
<br />Grand Canyon starting in the late 1800s (Fig. 6).
<br />Competition with and predation by these fishes is also
<br />a large factor in the decline of the native species
<br />(Valdez and Ryel, 1995).
<br />Few of the currently listed endangered fish in the
<br />Colorado River were caught or seen by pre-dam river
<br />runners (Table 7). The Stanton expedition (1889-
<br />1890), caught Colorado pikeminnow, and in 1911, the
<br />Kolb brothers caught 23 "bony tail" chub and one
<br />pikeminnow (Fig. 7b; Kolb, 1914). In 1923, Emery
<br />Kolb caught a "boneytail fish" near Mohawk Canyon
<br />(mile 171.5-L). Photographs (Fig. 7) show that most of
<br />the fish referred to as bony tail probably were
<br />humpback chub, which was not described as a species
<br />
<br />until 1946 (Miller 1946). The holotype used by RR
<br />Miller to describe the humpback chub was taken by N.
<br />N. Dodge angling with hook and line near Phantom
<br />Ranch in 1942. In 1940, Goldwater mentions catching
<br />"salmon" (Colorado pikeminnow) in the mouth of
<br />Shinumo Creek (mile 108.6-R) in addition to catfish.
<br />Nevills observed 4-in. suckers and 2-in. minnows in
<br />Shinumo Creek, 2.5 miles upstream from the Colorado
<br />River. Humpback chub and razorback sucker were not
<br />specifically mentioned, but "humpbacked suckers"
<br />were caught in Shinumo Creek and near Gneiss
<br />Canyon Rapid (mile 236; see Table 7). Although most
<br />fishermen caught trout in Tapeats Creek (mile 133.8-
<br />R), John Doerr, the chief naturalist at Grand Canyon
<br />National Park, caught Colorado pikeminnow there in
<br />1948.
<br />Some Old Timers remember seeing fishermen
<br />along the river, particularly in the first 32 miles
<br />downstream of Lee's Ferry. Nevills observed a fishing
<br />boat pulled up on the bank at mile 187 in 1947. Many
<br />trips included fishermen, which led to many
<br />observations about the kinds of fish in the river.
<br />Dynamite was commonly used to kill fish at Lee's
<br />Ferry (Table 7), and Frank Dodge, a river runner and
<br />U.S. Geological Survey employee in the 1930s and
<br />1940s, was one of its biggest users. Cross Sr. talked
<br />with Bert Loper about fishing in Glen Canyon in the
<br />1940s; dynamiting earlier in the century yielded
<br />Colorado pikeminnow, whereas later dynamiting
<br />yielded only catfish. Nevills found a cache of dynamite
<br />at the mouth of Parashant Wash (mile 198.5-R) in
<br />1942, that he thought was used for fishing. Rigg and
<br />Nichols saw dynamite being used to fish for catfish at
<br />Whitmore Wash (mile 188.1-R) in the 1950s.
<br />Catfish were extremely common and are
<br />mentioned in every fishing reference after 1938, except
<br />most years at Tapeats Creek (mile 133.8-R). Before
<br />1938, no fisherman reported catching catfish despite
<br />
<br />SPECIFIC CHANGES OBSERVED IN GRAND CANYON 29
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