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4 preparing a management plan for the protection of the Little Colorado River basin. This management plan should be developed, implemented, and funded by those with direct land management responsibility. The Navajo Nation is working in this area. - Interrelated and Interdeoendent Actions We are in agreement with the Service's assessment of interrelated and interdependent actions contained in the discussion of environmental baseline in the DBO. Determination of Jeooardy It is not clear from the information presented how the Service can determine that the Federal action of operating Glen Canyon Dam according to the MLFF Alternative creates a jeopardy situation when compared against the No Action environmental baseline. Habitat maintenance and habitat/beach building flows are a part of the proposed action and are committed to in the EIS and long- term monitoring and research program. As stated on page 26 of the DBD, these regulated flood flows would be expected to provide benefits to native fish.. These actions should also result in improvements to critical habitat. The Grand Canyon population of humpback chub does not appear to be in eminent danger of extinction. It has persiste.d in the Grand Canyon under the altered {{ flow regimes of the No Action Alternative, and more recently interim flows, . for a period totaling 30 years. During this period of time the population has been sustained as a stable~seJf Derpetuatino DODulatiop due to its ability to . . successfully reproduce 1n tne lCR. Current data collected through the GCES endangered fish program show a population that fits a typical, healthy, bell- shaped curve. However, the humpback chub population does show variability in number from year-to-year in response to the hydrology and other environmental variables in the system not controlled by Glen Canyon Dam. A showing of adverse effect does not necessarily violate section 7(a)(2), because the jeopardy standard is the ultimate barrier through which Federal agencies may not pass in conducting their actions (FR, Vol. SI, No. I06, P19931). The DBO indicates that the number of backwaters in the vicinity of the LCR during summer months at operating levels of the preferred alternative is a negative aspect of the MLFF Alternative. The Service concludes that to prevent jeopardy to the endangered fish, known limiting factors should be reduced to the extent pOSSible. Backwaters have been used as indicators of available aquatic habitat for larval fish. However, the number of backwaters in the vicinity of the LCR is not a scientifically supported limiting factor in the Grand Canyon. It is scientifically supported that young humpback chub do use near short habitats. In order to use backwaters as "indicators" of available habitat, it is necessary to conduct a more extensive analysis of the use of the backwaters by native and non-native fish and to study the competitive exclusion aspect of the two fish assemblages.