Report: Actions to protect fish in California Bay-Delta scientifically justified “

The action is conceptually sound that the amount of habitat available for smelt limits their abundance, but no details of the derivation of rigor, the committee said. The Committee noted that the needs of adaptive management action should be implemented in the light of the uncertainty in the biological actions of water and needs the highest possible.Report: a scientific evaluation of alternatives to reduce impacts on water management of threatened and endangered fish in California Bay Delta

For his study, the committee that wrote the report on an action in the alternative FWS to protect the delta smell limiting the amount of water is pumped from the Delta to reduce reverse flows in Old and Middle rivers, two branches of the San Joaquin River. The Committee concluded that, in winter, the river runs high contrast ratios, high pumping can damage the smell. However, the data do not allow the secure identification to reduce the reverse flow of the river or fish perceive a reliable assessment of performance by reducing the reverse flow, the committee found. Consequently, the implementation of this action must be accompanied by careful monitoring, adaptive management, and further analysis.

Most of the actions proposed by the two federal agencies to reduce water diversions in the Bay-Delta in California to protect fish species threatened with extinction and are scientifically justified but the basis of specific environmental factors that indicate when water diversions should be reduced is less well supported by scientific analysis, according to a new report by the National Research Council that was requested by Congress and the U. S. Department of the Interior.

In addition, the FWS requirement for the creation or rehabilitation of 8,000 hectares of intertidal and subtidal habitat in the delta is poorly justified, because the relationship between tidal habitats and food availability for smell is poorly understood. Since the details of implementation are not fully justified in the opinion of the biological, the Committee recommends that this action will be carried out in stages, the first to include an implementation plan and adaptive management. The Committee also recommended to consider the feasibility of habitats derived from them.

The Committee also considered whether additional measures not included in the biological opinion may have the potential to provide an equal or greater protection for the fish that the current requirements, and costs less in terms of availability of water for other uses. The Committee noted that no one who had received sufficient documentation or evaluation to be sure that any action had the potential to achieve this goal, but consider alternatives in more detail in its second report.

With regard to the opinion of the NMFS Biological applicable to salmon chinook, steelhead and sturgeon in the Delta and Green Mount, the committee concluded that the assessment of the actions are scientifically justified. In particular, the NMFS alternative contains an action similar to the action FWS to limit pumping to reduce high reverse flows in the rivers and the Middle and the Committee also found that the river flows may affect the other high-fish, but the scientific support for specific target flow is less certain. The Committee also found it difficult to determine the extent to which the action depends on collective activity and significantly reduce the risk to fish in the basin or along the river system and recommended quantities to create a framework to assess survival.

The California Bay-Delta region receives its fresh water from the Sacramento and San Joaquin and their tributaries, and water flows in the Delta last San Francisco Bay and the Pacific Ocean. Tidal mixing in the Pacific Ocean also occurs, resulting in a brackish water ecosystem in many parts of the delta. In addition, pumping stations to divert water from the delta, mainly for agriculture and the Central Valley of Southern California metropolitan areas.

Adverse effects of all the other stressors listed fish – as contaminants in the delta and structures that fish in the rivers prevent access to spawning habitat – are potentially important, the committee concluded, was asked to examine the effects of other stressors, if time permits. The limited time to complete the first report did not allow full exploration of the problem, but the committee will examine in detail in his second report, scheduled to be released next year.

In addition, the Committee considered that the assessments and rating agencies have been hampered by the lack of an integrated analysis that took all aspects of the life cycles of fish ‘into consideration, examined the effects of all actions and species fish together, and included clear and well documented considerations of water needed to implement the actions.