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Other rare and poorly known
<br />aquatic animals also inhabited Green
<br />River between Hideout Canyon art'd
<br />Vernal, Utah. George F. Edmunds, Jr.,
<br />of the University of Utah, has, since
<br />1947, been studying the insect life in
<br />Green River, between Green River,
<br />Wyomint, and Vernal, Utah. These
<br />animals are of great biological in-
<br />terest, for several mayflies reach the
<br />western limits of their distribution in
<br />this river, others are related to kinds
<br />that live far to the south of Utah, and
<br />others are known only from this section
<br />of Green River. In his investigation of
<br />these animals in the river, between
<br />Split Mountain (near the lower end of
<br />Dinosaur National Monument) and
<br />Vernal, Utah, made three wee after
<br />the poisoning project terminated, Pro-
<br />fessor Edmunds found disappointingly
<br />few aquatic insects. Many attempts at
<br />recovery, using hand screens, yielded
<br />no insects at all. He took neither dob.
<br />sonffies (of which the larvae are the
<br />hellgrammites familiar to fishermen
<br />and others) nor dragonflies. Both of
<br />these types of insects require more
<br />than one year to develop, so that their
<br />absence cannot be explained by assum-
<br />ing that they had already emerged
<br />from the water. He concluded further
<br />that the mayflies-of great importance
<br />in the food cycle of many fisheswere
<br />present in less than 10 percent of their
<br />normal populations, except that one
<br />kind that burrows deeply in the sand
<br />escaped the lethal effects of the rote-
<br />none.
<br />Verbal reports relayed to Dr. Ed-
<br />munds indicated that fishes also had
<br />been seriously affected by the rotenone
<br />as far as 110 river miles below the
<br />terminus of the poisoning project. (It
<br />is 108river miles from Ashley Dam-
<br />where the operation should have ter-
<br />minated-to the bridge at Jensen,
<br />Utah.) The tragedy of the Green -River
<br />project to the scientific study of in-
<br />sects was twofold: (1) Since Dr. Ed-
<br />munds and others were "assured" that
<br />the poison would not affect insect life
<br />below Ashley Dam, they, made no at-
<br />tempt to work in the river during the
<br />poisoning operation; and (2) the tens
<br />of thousands of valuable specimens
<br />killed were not recovered, including
<br />many kinds that are difficult to collect,
<br />and it is not unlikely that some species
<br />were exterminated. Nothing seems to
<br />be known of other invertebrates of the
<br />river, especially microscopic farms,
<br />and of how they fared in this tragedy.
<br />However, it is known that the effects
<br />of rotenone on such life in freshwater
<br />lakes are considerable (Almquist,
<br />1959; Kiser, Donaldson, and Olson,
<br />1963). It is quite possible that some
<br />species adapted to the swifter waters
<br />were eliminated even before having
<br />been collected.
<br />The Detoxification Program
<br />An attempt was made to detoxify the
<br />rotenone, but not at the base of the
<br />dam in Flaming Gorge (Wyoming
<br />Game and Fish Dept., 1962, p. 3, not.
<br />withstanding)-beyond which point
<br />there was no justification for destruc.
<br />tion of aquatic animals. Instead the
<br />station was placed 30 miles down-
<br />stream from the Dam, at Browns Park
<br />Bridge in Colorado, and only 16 miles
<br />above the upper boundary of Dinosaur
<br />National 114onument. In his letter of
<br />October 12, 1961, to Representative
<br />Bob Wilson (California) -who had ex-
<br />pressed concern over the threat to
<br />aquatic life in Dinosaur National
<br />Monument-Daniel H. Janzen (then
<br />Acting Commissioner of the U. S. Fish
<br />and Wildlife Service) assured Mr. Wil-
<br />son that there was no such danger in
<br />the following words: "This treatment
<br />would affect the Green River and its
<br />tributaries only within the States of
<br />Utah and Wyoming. Some effects may
<br />extend a few miles downstream from
<br />the dam, but it is not likely that they
<br />will reach Colorado. Rotenone is rather
<br />unstable in solution and is effective for
<br />only a short time. In streams, it may
<br />become non-toxic within ten miles
<br />from where it is introduced." Earlier,
<br />on September 20, 1961, in his letter to
<br />Dr. Carl L. Hubbs, Mr. Janzen (then
<br />writing as director of the Bureau of
<br />Sport Fisheries and Wildlife) stated:
<br />"As you are no doubt aware, the Colo.
<br />rado River Wildlife Management Com-
<br />mittee, as well as the fish and game
<br />departments of Colorado, Utah, and
<br />Wyoming, have subscribed to the
<br />Flaming Gorge fish eradication pro-
<br />gram to follow closure of the dam."
<br />Despite these two statements, (1) no
<br />attempt was made to detoxify the poi-
<br />son until after it bad entered Colorado,
<br />(2) the effects of the rotenone carried
<br />far more than 115 miles below the last
<br />station (about 8 miles above Ashley
<br />Dam) where it vas introduced. de-
<br />spite attempts to eliminate the toxic' t)
<br />of the chemical, and (3) when it was
<br />known that there would be a delay in
<br />closure of the dam (which occurred
<br />on November 1, 1962), the project
<br />was carried out anyway, thus allowin^
<br />a greater quantity of rotenone to pass
<br />downstream.
<br />Although large quantities of potas-
<br />sium permanganate were applied to the
<br />river at Browns Park Bridge, Colorado,
<br />from about 6 k.m. September 7 to
<br />about 5 P.m. September 11, 1962, this
<br />failed to provide downstream protec-
<br />tion for aquatic animals into, through,
<br />and beyond Dinosaur National Monu-
<br />ment. Despite this failure, which was
<br />known to authorities on or before Sep-
<br />tember 15, the Utah Department of
<br />Fish and Game authorized the publica-
<br />tion in November of the following
<br />statement: "One unique feature of the
<br />treatment was the successful operation
<br />of a detoxification station to neutralize
<br />the rotenone-bearing river water before
<br />it reached Dinosaur (National Monu-
<br />ment. Detoxification on this scale had
<br />not been considered feasible before but
<br />was necessary on the Green River to
<br />insure that fish species within the Mon-
<br />ument would remain unchanged." (Re-
<br />genthal, 1962). Although careful tests
<br />and checks of the effectiveness of rote-
<br />none to kill Green River fishes ivere
<br />carried out by Wyoming and Utah
<br />prior to the start of the eradication
<br />project, no such advance precautions
<br />were taken to determine whether the
<br />toxicant would be detoxified by potas-
<br />sium permanganate under the field con-
<br />ditions where it was applied. In fact.
<br />no adequate research had been carried
<br />out in this country on the detoxification
<br />ability of potassium permanganate in
<br />rivers approaching the size and the
<br />physical and chemical characteristics
<br />of Green River, and hence there was no
<br />advance assurance that it would do the
<br />job there. That it failed is not, there-
<br />fore, surprising.
<br />Research and Cooperation
<br />Conservation departments need to
<br />find out what the rare, threatened, or
<br />scientifically important species are so
<br />as to avoid the possibility of exter-
<br />minating populations before undertak-
<br />ing the application of toxicants. By
<br />doing this and by notifying interested
<br />MAY 1%3
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