Daily Rules, Proposed Rules, and Notices of the Federal Government
This action is part of the recovery actions that the Service, Federal and State agencies, and other partners are conducting throughout the historic range of the species. This final rule
It is our intent to discuss only those topics directly relevant to the establishment of a Rio Grande silvery minnow NEP in this final rule. For more information on the Rio Grande silvery minnow, refer to the September 5, 2007, proposed rule (72 FR 50918) and the Rio Grande Silvery Minnow Draft Revised Recovery Plan (Service 2007a) (Draft Revised Recovery Plan).
The Act provides that species listed as endangered or threatened are afforded protection primarily through the prohibitions of section 9 and the requirements of section 7. Section 9 of the Act, among other things, prohibits the take of endangered wildlife. “Take” is defined by the Act as harass, harm, pursue, hunt, shoot, wound, kill, trap, capture, or collect, or attempt to engage in any such conduct. Service regulations (50 CFR 17.31) generally extend the prohibitions of take to threatened wildlife. Section 7 of the Act outlines the procedures for Federal interagency cooperation to conserve federally listed species and protect designated critical habitat. It mandates that all Federal agencies use their existing authorities to further the purposes of the Act by carrying out programs for the conservation of listed species. It also states that Federal agencies will, in consultation with the Service, ensure that any action they authorize, fund, or carry out is not likely to jeopardize the continued existence of a listed species or result in the destruction or adverse modification of designated critical habitat. Section 7 of the Act does not affect activities undertaken on private land unless they are authorized, funded, or carried out by a Federal agency.
Under section 10(j) of the Act, the Secretary of the Department of the Interior can designate reintroduced populations established outside the species' current range, but within its historical range, as “experimental.” With the experimental population designation, the relevant population is treated as threatened for purposes of section 9 of the Act, regardless of the species' designation elsewhere in its range. Threatened designation allows us greater discretion in devising management programs and special regulations for such a population. Section 4(d) of the Act allows us to adopt whatever regulations are necessary and advisable to provide for the conservation of a threatened species. In these situations, the general regulations that extend most section 9 prohibitions to threatened species do not apply to that species, and the 10(j) rule contains the prohibitions and exemptions necessary and appropriate to conserve that species.
Based on the best scientific and commercial data available, we must determine whether the experimental population is
For the purposes of section 7 of the Act, we treat an NEP as a threatened species when the NEP is located within a National Wildlife Refuge or National Park, and section 7(a)(1) and the consultation requirements of section 7(a)(2) of the Act apply. Section 7(a)(1) requires all Federal agencies to use their authorities to carry out programs for the conservation of listed species. Section 7(a)(2) requires that Federal agencies, in consultation with the Service, insure that any action authorized, funded, or carried out is not likely to jeopardize the continued existence of a listed species or adversely modify its critical habitat. When NEPs are located outside a National Wildlife Refuge or National Park, we treat the population as proposed for listing, and only two provisions of section 7 apply—section 7(a)(1) and section 7(a)(4). In these instances, NEPs provide additional flexibility because Federal agencies are not required to consult with us under section 7(a)(2). Section 7(a)(4) requires Federal agencies to confer (rather than consult) with the Service on actions that are likely to jeopardize the continued existence of a species proposed to be listed. The results of a conference are in the form of conservation recommendations that are optional as the agencies carry out, fund, or authorizeactivities. Activities that are not carried out, funded, or authorized by Federal agencies and are not on Federal lands are not affected by an NEP designation.
Rio Grande silvery minnows that are used to establish an experimental population may come from a donor population, provided their removal will not create adverse impacts upon the parent population, and provided appropriate permits are issued in accordance with our regulations (50 CFR 17.22) prior to their removal. In the case of the Rio Grande silvery minnow, the donor population is a captive-bred population that was propagated with the intention of re-establishing wild populations to achieve recovery goals. In addition, it is possible that stock raised from wild eggs could also be released into the NEP area. Rio Grande silvery minnow eggs are collected from the wild population in New Mexico each year and are raised in captivity to provide individuals for captive propagation and augmentation of the wild population.
Critical habitat has been designated for the Rio Grande silvery minnow in New Mexico (68 FR 8088-8135; February 19, 2003), and the designated critical habitat does not include this NEP area. Section 10(j)(2)(C)(ii) of the Act states that critical habitat shall not be designated for any experimental population that is determined to be nonessential. Accordingly, we cannot designate critical habitat in areas where we have already established an NEP.
The Rio Grande silvery minnow is one of seven species in the genus Hybognathus found in the United States (Pflieger 1980, p. 177). The species was first described by Girard (1856 in Service 1999, p. 38) from specimens taken from the Rio Grande near Fort Brown, Cameron County, Texas. It is a stout silvery minnow with moderately small eyes and a small, slightly oblique mouth. Adults may reach 5 inches (in)
This species was historically one of the most abundant and widespread fishes in the Rio Grande Basin, occurring from Española, New Mexico, to the Gulf of Mexico (Bestgen and Platania 1991, p. 225). It was also found in, but is now absent from, the Pecos River, a major tributary of the Rio Grande, from Santa Rosa, New Mexico, downstream to its confluence with the Rio Grande (Pflieger 1980, p. 177). The Rio Grande silvery minnow is extirpated from the Pecos River and also from the Rio Grande downstream of Elephant Butte Reservoir and upstream of Cochiti Reservoir (Bestgen and Platania 1991, pp. 226-229). The current distribution of the Rio Grande silvery minnow is limited to the Rio Grande between Cochiti Dam and Elephant Butte Reservoir in New Mexico, which is only about 5 percent of its historical range (Bestgen and Platania 1991, pp. 226-229). Throughout much of its historical 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, decreasing water quality, and perhaps interactions with nonnative fish (Cook
The various life history stages of the Rio Grande silvery minnow require low-velocity habitats with a sandy and silty substrate that is generally associated with a meandering river that includes side channels, oxbows, and backwaters (Bestgen and Platania 1991, pp. 227-228). It is not uncommon for Rio Grande silvery minnows in captivity to live beyond 2 years (Service 2007a, p. 8). However, although the Rio Grande silvery minnow is a hardy fish, capable of withstanding many of the natural stresses of the desert aquatic environment, its maximum documented longevity in the wild is about 25 months, and very few survive more than 13 months. Thus, a successful annual spawn (reproductive event) is key to the survival of the species (Service 1999, p. 20; Dudley and Platania 2001, pp. 16-21; Dudley and Platania 2002, p. 3). More information about the life history of, decline of, and threats to the Rio Grande silvery minnow can be found in the final designation of critical habitat for the species (February 19, 2003; 68 FR 8088-8090), in the Rio Grande Silvery Minnow Recovery Plan (Recovery Plan; Service 1999, pp. 1-38), and the Draft Revised Recovery Plan (Service 2007a).
The Rio Grande silvery minnow is extirpated from the Big Bend reach of the Rio Grande (Service 2007a, p. 10). The last documentation of a Rio Grande silvery minnow in the Big Bend reach of the Rio Grande was in 1960 (Bestgen and Platania 1991, p. 229). Natural repopulation is not possible without human assistance due to extensive reaches of river lacking Rio Grande silvery minnow habitat (including large reservoirs, where this species cannot survive) between where the species currently exists in the wild in New Mexico and the Big Bend reach.
The Service contracted a study examining the suitability of the habitat in the Big Bend reach of the Rio Grande for the Rio Grande silvery minnow (Edwards 2005). The completed study indicates that there is a reasonable likelihood that Rio Grande silvery minnows will survive in this portion of the Rio Grande and become established. It also identifies the need for habitat restoration projects, with an emphasis on the removal of nonnative species, such as salt cedar (
Throughout most of the NEP area, the lands along the Rio Grande are protected and managed on both the United States and Mexico side of the border by Federal, State, and private conservation-oriented landowners. These entities are all working together to conserve the aquatic and riparian habitats along 281 miles (452 kilometers) of the Rio Grande/Rio Bravo. This provides a unique and significant measure of protection for the Rio Grande silvery minnow in the NEP area. We anticipate working with land managers and other interested parties, on a voluntary basis, to develop plans to further guide and accomplish habitat management and restoration activities, including removal and control of nonnative species, such as salt cedar and giant river cane.
We published the final rule to list the Rio Grande silvery minnow as an endangered species on July 20, 1994 (59 FR 36988). Restoring an endangered or threatened species to the point where it is recovered is a primary goal of our endangered species program. Thus, on July 1, 1994, the Rio Grande Silvery Minnow Recovery Team (Recovery Team) was established under section 4(f)(2) of the Act and our cooperative policy on recovery plan participation, a policy intended to involve stakeholders in recovery planning (July 1, 1994; 59 FR 34272). Numerous individuals, agencies, and affected parties were involved in the development of the Recovery Plan or otherwise provided assistance and review (Service 1999, pp. 63-67). On July 8, 1999, we finalized the Recovery Plan (Service 1999, 71 pp.). The Recovery Plan has been updated and revised, and the Draft Revised Recovery Plan (Service 2007a) was released for public comment on January 18, 2007 (72 FR 2301). The Draft Revised Recovery Plan is currently in the process of being finalized, and thus, the final published version could be slightly different. In implementing and evaluating the success of this reintroduction effort, we will rely on the information in the Draft Revised Recovery Plan until the final revised Rio Grande Silvery Minnow Recovery Plan is published.
The Draft Revised Recovery Plan describes recovery goals for the Rio
(1) Prevent the extinction of the Rio Grande silvery minnow in the middle Rio Grande of New Mexico;
(2) Recover the Rio Grande silvery minnow to an extent sufficient to change its status on the List of Endangered and Threatened Wildlife from endangered to threatened (downlisting). This may be considered when three populations (including at least two that are self-sustaining) of the species have been established within the historical range of the species and have been maintained for at least 5 years; and
(3) Recover the Rio Grande silvery minnow to an extent sufficient to remove it from the List of Endangered and Threatened Wildlife (delisting). This may be considered when three self-sustaining populations have been established within the historical range of the species, and they have been maintained for at least 10 years (Service 2007a, p. 66).
The Rio Grande silvery minnow's range has been so greatly restricted that the species is extremely vulnerable to catastrophic events, such as a prolonged period of low or no flow in its habitat in the middle Rio Grande in New Mexico (i.e., the loss of all surface water) (Dudley and Platania 2001, p. 21). Reestablishment of the Rio Grande silvery minnow in other areas of its historical range will assist in the species' recovery and long-term survival in part because it is unlikely that any single event would simultaneously eliminate the Rio Grande silvery minnow from three geographic areas (Service 1999, pp. 57-61).
The Recovery Team developed a reach-by-reach analysis of the Rio Grande and Pecos River basins to identify the salient hydrological, chemical, and biological features of each reach. This analysis addressed the threats to the Rio Grande silvery minnow and considered the suitability of each reach for potential reestablishment (Service 2007a, pp. 159-171). The Recovery Team's reach-by-reach analysis considered: (1) the reasons for the species' extirpation from the selected reach; (2) the presence of other members of the reproductive guild (pelagic spawner; non-adhesive, semibuoyant eggs); (3) habitat conditions (including susceptibility to river drying and presence of diversion structures); and (4) the presence of congeners (i.e., other fishes in the genus Hybognathus). After completing their analysis, the Recovery Team identified the Big Bend reach of the Rio Grande as the first priority for reestablishment efforts (Service 2007a, p. 160) (see “Reestablishment Area” below for more details).
In accordance with the Recovery Plan (Service 1999, pp. 60-61), we initiated a captive propagation program as a strategy to assist in the recovery of the Rio Grande silvery minnow in 2000. We currently have Rio Grande silvery minnows housed at: (1) the Service's Dexter National Fish Hatchery and Technology Center, Dexter, New Mexico; (2) the City of Albuquerque's Biological Park, Albuquerque, New Mexico; and (3) New Mexico State University, Las Cruces, New Mexico. These facilities are actively propagating and rearing Rio Grande silvery minnows. Offspring of these fish are currently being used to augment the Rio Grande silvery minnow population in the middle Rio Grande, New Mexico.
Ongoing recovery efforts involving the release of captive-bred Rio Grande silvery minnows for augmentation of the population in the middle Rio Grande of New Mexico have demonstrated the potential viability of reestablishment as a tool for Rio Grande silvery minnow conservation. Captive propagation is conducted in a manner that will, to the maximum extent possible, preserve the genetic and ecological distinctiveness of the Rio Grande silvery minnow and minimize risks to existing wild populations consistent with our 2000 policy for captive propagation (65 FR 56916) (Service 2007b, 26 pp.)
Since 2000, approximately one million silvery minnows have been propagated (using both adult wild silvery minnows and wild-caught eggs) and then released into the wild in the middle Rio Grande in New Mexico (Remshardt 2008, p. 23). Wild gravid adults are successfully spawned in captivity at the City of Albuquerque's propagation facilities. Eggs left in the wild in the Rio Grande in New Mexico have a very low survivorship because many of them end up in Elephant Butte Reservoir where there is no suitable habitat for the species and the eggs are subject to a high rate of depredation. Spawning in captivity ensures that an adequate number of spawning adults are present to repopulate the river each year. While hatcheries continue to successfully spawn silvery minnows, wild eggs are collected to ensure genetic diversity within the remaining population. This program is carefully monitored so that it will not have an adverse effect on the wild population of Rio Grande silvery minnows in New Mexico.
Direct and indirect evidence from the Rio Grande silvery minnow monitoring program indicates that augmentation efforts in the Rio Grande near Albuquerque, New Mexico, are contributing to an increase in catch rates (i.e., during seining) of marked and unmarked Rio Grande silvery minnows. The success of this augmentation effort indicates that hatchery-raised individuals can be released back to the wild with adequate retention in or near original release sites, experiencing survival of at least 2 years after release, and ultimately can contribute to future spawning efforts (Remshardt 2008, pp. 11-12).
The source of Rio Grande silvery minnows for releases in the Big Bend reach will likely be from the Service's Dexter National Fish Hatchery and Technology Center, or another Service facility set up to provide fish specifically for this purpose. Expanding the Rio Grande silvery minnow's propagation program for potential releases into the Big Bend reach will result in more fish being produced overall and will not negatively impact the current program, which is producing Rio Grande silvery minnows for augmentation of the population in New Mexico (Service 2007b, pp. 6-7, 17-18).
The primary factors resulting in the determination by the Recovery Team that the Rio Grande reach from Presidio to Amistad Reservoir is the most suitable area for reintroduction efforts are: water quality and quantity; the presence of suitable habitat; an absence of barriers to fish movement within the reach; a lack of ongoing activities that are likely to adversely affect the Rio Grande silvery minnow; and the presence of designated conservation areas on both sides of the river that are managed for habitat protection and improvement by the State of Texas, the National Park Service, and governmental agencies and private organizations in Mexico (Edwards 2005, p. 11).
River flow in the Big Bend reach is generally perennial, with a base flow of approximately 400 cubic feet per second (11.3 cubic meters per second). Severe flow reductions occurred only during the severest droughts in the 1950s. A period of intermittent drying did occur in 2003. However, this drying event appears to have been brief and occurred in a small area. In addition, this reach of the river does not have flood control levies. It also contains only a few small, rock dam weirs, all but one of which
Based on the above information, we believe that the Rio Grande, from Mulato Dam (near the western border of Big Bend Ranch State Park) to Foster's Weir, east of the Terrell/Val Verde county line (the expected extent of reestablishment), contains suitable habitat for the Rio Grande silvery minnow and that it is likely the species can be successfully reestablished in the Big Bend reach. Establishing a viable population of Rio Grande silvery minnows in the Big Bend reach of the Rio Grande under this NEP designation would help achieve one of the primary recovery goals for downlisting and eventually delisting this species (see “Recovery Efforts” section above for more information). It is expected to take multiple introductions and several years of monitoring to evaluate if Rio Grande silvery minnows have become established and can be self-sustaining in this river reach.
Therefore, we intend to release the Rio Grande silvery minnow into its historical habitat in this area. The NEP area, which encompasses all potential release sites, is located (1) in the Rio Grande, from Little Box Canyon downstream of Fort Quitman, Hudspeth County, Texas, through Big Bend National Park and the Rio Grande Wild and Scenic River, to Amistad Dam; and (2) in the Pecos River, from its confluence with Independence Creek to its confluence with the Rio Grande.
Section 10(j) of the Act requires that an experimental population be geographically separate from other wild populations of the same species. This NEP area is isolated from existing populations of this species by large reservoirs. This fish is not known to survive in or move through large reservoirs due to the presence of unsuitable habitat and predators (64 FR 36275); therefore, the reservoirs will act as barriers to the species' downstream movement in the Rio Grande below Amistad Reservoir, and will ensure that this NEP remains geographically isolated and easily distinguishable from existing upstream wild populations in New Mexico. Based on the habitat requirements of the Rio Grande silvery minnow, we do not expect them to become established outside the NEP because they are unlikely to move into the unsuitable habitat at the edges of the NEP beyond the expected extent of reestablishment and are not able to move past physical barriers (dams and weirs) at either end of the NEP.
The geographic extent of the NEP designation is larger than needed as only portions of the NEP area contain suitable habitat. However, as described above, this area represents what we believe to be the maximum geographic extent to which the fish could move if released in the Big Bend reach of the Rio Grande. We believe including this additional area provides a more effective recovery strategy by eliminating changing regulatory requirements in case Rio Grande silvery minnows unexpectedly move beyond the expected establishment area. If any of the released Rio Grande silvery minnows, or their offspring, move outside the designated NEP area, then the Service would consider these fish to have come from the NEP area, and we would propose to amend this 10(j) rule to enlarge the boundaries of the NEP area to include the entire range of the expanded populations.
Based on our experience with releasing the species to augment its population in New Mexico, we have determined that it would be best to release fish once per year in December or January. An implementation plan, including information about potential release sites, methods, and the number of individuals to be released, is appended to our environmental assessment (EA) and includes additional information on release sites, release timing, monitoring, and suggested management and research.
As part of the Rio Grande silvery minnow augmentation program in New Mexico, we evaluated different release strategies such as time of year, time of day, specific release habitats, and various hatchery environments (natural outdoor ponds versus indoor facilities). All of this information adds to our knowledge of the species and will assist us in future recovery actions, such as providing release procedures and monitoring strategies for the reestablishment of Rio Grande silvery minnows in the Big Bend reach.
As described in the Recovery Plan and the Draft Revised Recovery Plan, reestablishment of populations within the Rio Grande silvery minnow's historical range is necessary to further the conservation and recovery of this species (Service 2007a, p. 67). The anticipated success of this reestablishment would enhance the conservation and recovery potential of this species by extending its present range into currently unoccupied historical habitat (Service 2007a, pp. 159-171). However, as required by section 10(j)(2)(B) of the Act, we have determined that this experimental population is not essential to the continued existence of the species in the wild for the following reasons:
(1) We will ensure, through our section 10 permitting authority and the section 7 consultation process, that the use of Rio Grande silvery minnows from any donor population for releases in the Big Bend reach is not likely to jeopardize the continued existence of the species in the wild;
(2) A population of Rio Grande silvery minnows exists in the middle Rio Grande, New Mexico, and the possible failure of the NEP that is the subject of this rule will not appreciably reduce the likelihood of survival of the species' existing wild population. Captive propagation facilities maintain a captive population, maximizing genetic diversity to the extent possible, and provide adequate numbers of Rio Grande silvery minnows to maintain the wild New Mexico population and also provide fish for releases in the Big Bend reach. The additional number of Rio Grande silvery minnows needed for reestablishment in the Big Bend reach will not inhibit the population augmentation efforts in the middle Rio Grande, New Mexico; and,
(3) The captive population is protected against the threat of extinction from a single catastrophic event by housing Rio Grande silvery minnows in three separate facilities. Juvenile minnows produced in excess of the numbers needed to maintain the captive population and augment the wild population in New Mexico are available for reintroduction to the Big Bend reach. Some members of the experimental population are expected to die during the reintroduction efforts after removal from the captive population. The Service finds that even if the entire experimental population died, this would not appreciably reduce the prospects for future survival of the species in the wild. That is, the captive population could produce more surplus
In view of all these safeguards the Service finds that the reintroduced population would not be “essential” under 50 CFR 17.81(c)(2). Essential status for experimental populations is not required by section 10(j) of the Act or the implementing regulations, and it has not been used in past reintroductions of captive-raised animals, such as the red wolf (
Section 10(j) of the Act requires that an experimental population be geographically separate from other populations of the same species. On the Rio Grande, the geographic boundaries of the NEP extend from Little Box Canyon downstream of Fort Quitman, Hudspeth County, Texas, through Big Bend National Park and the Rio Grande Wild and Scenic River, to Amistad Dam (Big Bend reach of the Rio Grande). On the Pecos River, the geographic boundaries of the NEP extend from the river's confluence with Independence Creek to its confluence with the Rio Grande. The NEP area is isolated from the existing population of this species in New Mexico by hundreds of river miles, including large reservoirs and other areas of unsuitable habitat. The best available information indicates that large reservoirs serve as a barrier to movement for the Rio Grande silvery minnow because they contain many predators and do not contain suitable habitat for the species (64 FR 36275). These reservoirs will ensure that this NEP remains geographically isolated and easily distinguishable from existing upstream wild populations in New Mexico. In addition, Amistad Reservoir will act as a barrier to the species' downstream movement in the Rio Grande.
The aquatic resources in the reestablishment area are managed by the National Park Service, the International Boundary and Water Commission, the State of Texas, and private landowners. Multiple-use management of these waters will not change as a result of the experimental population designation. Agricultural, recreational, and other activities by private landowners within and near the NEP area will not be affected by this rule and the subsequent release of the Rio Grande silvery minnow. Because of the exceptions provided by NEP designation, we do not believe the reestablishment of Rio Grande silvery minnows will conflict with existing human activities or hinder public use of the area.
The Service, the National Park Service, the International Boundary and Water Commission, Texas Parks and Wildlife Department employees, and other conservation partners will plan and manage the reestablishment of Rio Grande silvery minnows. This group will closely coordinate on releases, monitoring, coordination with landowners and land managers, and public awareness, among other tasks necessary to ensure successful reestablishment of the species. The Service has also convened a Technical Team comprised of representatives from these agencies and other experts. This Technical Team assisted in the development of the Implementation and Monitoring Plan that is appended to the EA.
The propagation strategy is based on two key elements: (1) the collection of eggs from the middle Rio Grande to meet the majority of targeted stocking numbers, and (2) maintaining fish from the annual wild egg collection as broodstock in the event catastrophic changes occur in the river. These actions minimize the risk to the extant population by preventing broodstock mining and maximize the potential to replicate as closely as possible a natural recruitment cycle. The propagation program will be contingent on an orchestrated balance between the use of wild-caught eggs and captive propagation that will require ongoing monitoring of river populations and genetic monitoring of wild and captive stocks (Service 2007b, p. 2).
The propagation program will use a combination of wild-egg collections and hatchery spawning of fish from wild-eggs (F1) to produce fish for stocking. Eggs will be collected in the river every spring from natural spawning events and delivered to propagation facilities. The majority of these eggs drift into hostile waters such as Elephant Butte reservoir or river reaches that become dewatered. The eggs will be hatched, and larval fish reared to adulthood in captivity. A small portion from each year class will be retained as captive broodstock. If recruitment fails in any given year, the captive stock can be used to produce fish to maintain the species through the next year (Service 2007b, p. 2).
Additionally, paired or communal spawning will be conducted annually. Ongoing genetic monitoring will be used to ensure a minimum number of breeding animals contribute to the next generation. We expect that in low water years, when natural spawning is not expected to yield adequate numbers of eggs for the program, captive propagation will be required in terms of increasing the genetic effective population size, and to meet targeted stocking numbers (Service 2007b, pp. 2-3).
The Rio Grande Silvery Minnow Genetics Management and Propagation Plan is designed to provide a strategy for maintenance of genetic diversity in the species. In concert with strategies to address the underlying cause of the species' decline, fish from collected eggs and captively propagated fish will ensure long-term survival and recovery of the Rio Grande silvery minnow by providing offspring appropriate for reintroduction as identified in the Draft Revised Recovery Plan (Service 2007a) and in the Service's conservation strategy for the species (67 FR 39212).
We requested written comments from the public on the proposed NEP and draft EA in the proposed rule published on September 5, 2007 (72 FR 50918). We also contacted the appropriate Federal, State, and local agencies; Tribes; scientific organizations; and other interested parties and invited them to comment on the proposed rule. The initial comment period was open from September 5, 2007, to November 5, 2007. In response to requests from interested parties, a second comment period was open from February 22, 2008, through March 10, 2008 (73 FR 9755).
In accordance with our policy on peer review, published on July 1, 1994 (59 FR 34270), we solicited opinions from three expert aquatic biologists who are familiar with this species regarding pertinent scientific or commercial data and assumptions relating to supportive biological and ecological information for the proposed rule. Reviewers were asked to review the proposed rule and the supporting data, to point out any mistakes in our data or analysis, and to identify any relevant data that we might have overlooked. All three of the peer reviewers submitted comments and were generally supportive of the proposal to reestablish Rio Grande silvery minnow in the Big Bend reach. Their comments are included in the summary below and/or incorporated directly into this final rule.
We reviewed all comments received from the peer reviewers, State agencies, and the public for substantive issues and new information regarding the proposed NEP. Substantive comments received during the comment period have either been addressed below or incorporated directly into this final rule. The comments are grouped below as peer review, State, or public comments.
We received comments from 14 parties, including comments from natural resource management agencies
Comments in support of the proposed action by peer reviewers included agreement with the following determinations: (1) the proposed NEP is wholly separate geographically from existing populations of Rio Grande silvery minnows; (2) establishment of a second population of Rio Grande silvery minnows is essential for the recovery of the species; (3) the Big Bend reach of the Rio Grande likely provides the best location for a second population; and (4) it seems appropriate to assume that Rio Grande silvery minnows will not become established outside of the proposed NEP area. One peer reviewer also agreed with our assertion that the continuing presence of speckled chub (
Our intent is for the 10(j) rule to remain in place until the status of the species improves to a point where listing is no longer necessary, as defined by the Draft Revised Recovery Plan or the final revised version, and the Rio Grande silvery minnow can be delisted. Once the threats to the Rio Grande silvery minnow are reduced and at least three populations are self-sustaining, the Service will likely publish a proposed rule to delist the Rio Grande silvery minnow in the
Additionally, we note that conservation efforts by us and our conservation partners are always subject to funding support by Congress, State legislatures, or private individuals and organizations. Although we have no guarantees about funding in future years, we have a reasonable expectation that we and/or our partners will be able to carry out the monitoring activities that we have identified as appropriate. Please also see our response to Comment 3.
Please see the Biological Information section of this rule for a brief summary of potential threats to the species in the Big Bend reach. A more detailed summary and evaluation of potential threats to the species in the Big Bend reach can be found in the document, Feasibility of Reintroducing Rio Grande Silvery Minnows (
Until we release Rio Grande silvery minnows into the Big Bend reach and monitor the population, as well as that of other fish in the area, we do not know how Rio Grande silvery minnows will be affected by other native and non-native fish in this area. As the experimental reintroduction proceeds we will be gathering information to assist us in identifying and quantifying potential threats to the species in this area.
We believe that releasing Rio Grande silvery minnows under the section 10(j) NEP provision of the Act is the most appropriate way to achieve conservation for this species in the Big Bend reach and that this action is consistent with the purposes of the Act. In coordination with the Rio Grande Captive Propagation and Genetic Management Working Group and our permitting authorities under section 10 of the Act, we will ensure that our efforts to reestablish the species in the Big Bend reach do not adversely affect the wild population of Rio Grande silvery minnows in New Mexico.
Additionally, the NEP designation does not provide a mechanism for us to require upstream water users to provide water resources to the NEP area. If water was supplied to the NEP area from upstream water users to enhance or maintain flows it would be done as a voluntary conservation measure. In order to require that upstream users must deliver additional water resources downstream, we must determine that an action with a Federal nexus is causing jeopardy to the species and that the reasonable and prudent alternative to the proposed action was to let water down. Because this population has been determined to be nonessential to the existence of the species, we would not be able to make a determination of jeopardy to the species due to effects on the NEP. In other words, in order to determine if this population is “essential” or “nonessential” under section 10(j)(2)(B) of the Act, we have already found that the loss of the fish in the NEP area would not jeopardize the continued existence of the species. Thus, any projects occurring in the NEP area would not jeopardize the continued existence of the species and requiring water from upstream users would not be a necessity.