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59 <br />b. Devils Hole pupfish, Cyprinodon diabolis. <br />Jim Deacon reported that the recovery plan will be forwarded to Portland <br />next week. The water level of 2.7 established by Judge Foley is proving <br />to be helpful in the buildup of the population. Pre-pumping levels were <br />approximately 1.2-1.4. During the extremely low levels experienced during <br />pumping times, the population dropped below 100 fish. Since the level has been <br />stabilized at 3.0, it has never been less than 200. With the water level at or <br />above 2.7, Dr. Deacon expects the population to increase to over 500. Counts <br />are made once per month, and a maximum count of 525 was made last summer(1977). <br />Doug Selby's report on the Hoover Dam population follows: <br />During the past four censuses at the refugium the maximum population count <br />has varied from 41 to 48 fish. There is occasional evidence of reproduction <br />in the form of young fish. A build up of sediment on the bottom of the <br />refugium may be partially responsible for the decline in reproductive success <br />and population numbers. Because of this, attempts are being made to siphon <br />off this sediment in hopes of increasing the population. <br />c. Ash Meadows speckled dace, Rhinichthys osculus nevadensis. <br />Gail Kobetich reported that most of the good habitat for the subspecies has <br />been removed. Because of this and other uncertainties in the Ash Meadows <br />area, he will suggest that it be listed as endangered. <br />d. Ash Meadows pupfish, Cyprinodon nevadensis mionectes. <br />The existing populations are holding their own. However, it is also suggested <br />for listing as at least threatened status under the same rationale listed under <br />(c) above. <br />e. Warm Springy pupfish, Cyprinodon nevadensis pectoralis. <br />Doug Selby's report follows: <br />A habitat management recommendation has been prepared outlining a procedure <br />to eradicate the exotic fish species from habitats of the Warm Springs <br />pupfish. The habitats presently containing exotics are both Scrugg's Springs <br />and both Indian Springs. The proposal calls for installation of fish <br />barriers on the outflow of each of the springs. A low gradient barrier <br />of the type successfully used at Fish Slough (Mono County, California) will <br />be constructed for this purpose. The springs will be seined and trapped to <br />remove the largest number of C. n. Pectoralis. The fish will be held in <br />separated, labeled cages at the nearby Amargosa Pupfish Refugium. The springs <br />will then be treated with Antimycin concentrate distributed from drip stations <br />above the first occurrence of exotic fishes. After detoxification the fish <br />will be returned to their respective habitats.