Comment on FR Doc # E8-03385

??Attn: RGSM Proposed 10(j) Designation,?? Comment number 1. In the DEA, Recommended Research, item "3. Develop a better understanding of water quality in the Rio Grande within and upstream of the reestablishment area, including water entering from the Rio Conchos." I think that its important that the "understanding of water quality" be directly linked to the direct or indirect response of the silvery minnow and/or the quality of their habitat (physical, chemical or biological characteristics - food, effect on competition or predation, disease, parasite burden, etc.). For example, water quality studies that emphasize or evaluate conditions for human health or their recreation in the water may, or may not, provide the appropriate level of understanding of the quality of water and how it will affect the survivability, growth or reproduction of the Rio Grande silvery minnow. I'd recommend that your item 3 be modified to state: "3. Develop a better understanding of water quality in the Rio Grande as it affects the health of Rio Grande silvery minnow or the quality of its essential fish habitat within and upstream of the reestablishment area, including water entering from the Rio Conchos." Essential fish habitat could be defined as those "wasters and substrate necessary for feeding, spawning, reproduction, cover, movement, or growth to maturity" and include aquatic areas and their associated physical, chemical, radiological and biological properties that are used by the Rio Grande silvery minnow." It appears the DEA downplays the potential for the quality of water to affect, in some regard, the survival of some fish or the recovery of the Rio Grande silvery minnow in this reach. "This species 'may' also be affected by water quality declines and interactions with non-native fish." Buhl (2002) demonstrated empirically that whenever water quality is insufficient (e.g., the content of dissolved oxygen in the water drops precipitously, or the concentration of ammonia or copper is sufficiently elevated), then Rio Grande silvery minnow will die, unequivocally. Rio Grande silvery minnow are not somehow immune or resistant to a precipitous decline of water quality sufficient to suggest that they "may" be affected; rather they shall be affected, especially when conditions have declined to the extent that they are detrimental to aquatic life. The statements in the proposed rule and the DEA should be more objective in this reguard about this phenomena, ("Throughout much of its historic range, the decline of the Rio Grande silvery minnow has been attributed to modification of the flow regime (hydrological pattern of flows that vary seasonally in magnitude and duration, depending on annual precipitation patterns such as runoff from snowmelt), channel drying, reservoirs and dams, stream channelization, as well as interactions with nonnative fish and decreasing water quality (Cook et al. 1992, p. 42; Bestgen and Platania 1991, pp. 229?230; Service 1999, pp. 1?2). rather than include "perhaps" in the statement or have another sentence addenda as provided in the DEA and therefore, I recommend that these documents be modified to reflect the final rule to list the species - that is, whenever water quality declines the species responds and its habitat is degraded from an optimal condition and indeed, whenever water quality declines sufficiently, silvery minnow will die - its not a phenomena this species somehow skirts - certainly they are hardy animals, but they are not immune to water quality degradation as the qualifiers "perhaps" and "may" suggest. This tenuousness about the health of fish (and other organisms) and the decline of water quality should either be expressed more empirically and supported and certainly qualified by the need for additional research. The Service could offer more empirical data rather than "a belief" that is offered in the proposed rule, (proposed rule, page 50920); "we do not believe it is a primary determinant of the survivability of the Rio Grande silvery minnow in this reach (citing Edwards 2005). A review of Edwards (2005) in context (page 26) stated: "Overall, there are some chemical contaminants present in this reach of the river in various concentrations that may be having negative effects on the aquatic fauna. However, because many of these tend to have low (or lowering) levels through time, and the few studies on the aquatic biota have not demonstrated large-scale deleterious impacts, it is not thought that water quality is a primary determinant of the survivability of the Rio Grande silvery minnow in the reach. Regular monitoring efforts should help in preventing sustained impacts from chemical contaminants." In context, it is clear that Edwards was providing a supposition, as there were no empirical studies cited to provide support to this thought. And while water quality is identified as not a primary determinant, this suggests the Service knows which stressor are determinants of survivorship and therefore they should be listed in order of importance in the DEA. Elsewhere in the document, Edwards (2005, page 11) is more circumspect, stating, "Poor water quality from Rio Conchos inflows, loss of the natural hydrograph and diversion (de-watering) are the primary candidates for the loss of the species in this reach. (draft Rio Grande Silvery Minnow Recovery Plan Update, 2004)." Additionally, if the Service is going to depend on the improvement of "water quality levels" as an indicator of likely survivorship of the Rio Grande silvery minnow - it should be clear about whether and to what extent the characteristics of the essential fish habitat that lead to the survivorship, growth, health or reproductive success of the Rio Grande silvery minnow were measured or if any water quality trend is a sufficient indicator. For example, if the concentration of bacteria in the water were improved, would that indicator be sufficient to reflect the water quality conditions that may affect the Rio Grande silvery minnow and suggest they were also improved or has the link between bacteria as a water quality indicator not been sufficiently linked to the qualities of the Rio Grande silvery minnow essential fish habitat and their health and reproductive success. That said, the Service could be more objective in its statements about the likely impacts of water quality declines to Rio Grande silvery minnow and emphasize the need for additional research to obtain that information. The use of the qualifiers "may" and "perhaps" do not appear to be supported by the best available scientific information. Citations: Buhl, K.J. 2002. The relative toxicity of inorganic contaminants to the Rio Grande silvery minnow (Hybognathus amarus) and fathead minnow (Pimephales promelas) in a water quality simulating that in the Rio Grande, New Mexico. Final Report to the U.S. Fish and Wildlife Service, Study No. 2F33-9620003. U.S. Geological Survey, Columbia Environmental Research Center, Yankton Field Research Station, Yankton, South Dakota. Available from the Website - http://www.cerc.usgs.gov/pubs/center/pdfDocs/Silvery_Minnow.pdf Edwards, Robert J. 2005. Feasibility of Reintroducing Rio Grande Silvery Minnows (Hybognathus amarus) to the Rio Grande, Big Bend Region, Texas. Final Report to the U.S. Fish and Wildlife Service.