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###### Department of the Interior

###### Fish and Wildlife Service

          - 50 CFR Part 17
          - [Docket No. FWS-R6-ES-2019-0055; FF09E22000 FXES11130900000 201]
          - RIN 1018-BD49

# AGENCY:

Fish and Wildlife Service, Interior.

# ACTION:

Final rule.

# SUMMARY:

                         We, the U.S. Fish and Wildlife Service (Service), are removing the Kanab ambersnail (                        *Oxyloma haydeni kanabensis*) from the Federal List of Endangered and Threatened Wildlife. This determination is based on a thorough review of the best available scientific information. Our review indicates that the Kanab ambersnail is not a valid subspecies and therefore cannot be listed as an endangered entity under the Endangered Species Act.                    

# DATES:

This rule is effective July 26, 2021.

# ADDRESSES:

                        This final rule, the supporting documents we used in preparing this rule, and public comments we received are available on the internet at                         *http://www.regulations.gov*                         at Docket No. FWS-R6-ES-2019-0055. Persons who use a telecommunications device for the deaf may call the Federal Relay Service at 800-877-8339.                    

# FOR FURTHER INFORMATION CONTACT:

Yvette Converse, Field Supervisor, telephone: 801-975-3330. Direct all questions or requests for additional information to: Kanab Ambersnail Questions, U.S. Fish and Wildlife Service; Utah Ecological Services Field Office; 2369 Orton Circle, Suite 50; West Valley City, Utah 84119. Persons who use a telecommunications device for the deaf may call the Federal Relay Service at 800-877-8339.

# SUPPLEMENTARY INFORMATION:

## Previous Federal Actions

                    On November 15, 1991, we proposed to list the Kanab ambersnail as an endangered species (56 FR 58020). The species' habitat was greatly reduced in size and the population declined, due to preparations for anticipated development. On April 17, 1992, we published a final rule listing the Kanab ambersnail as an endangered species (57 FR 13657), but as explained in that rule,                           ( print page 33138)                        we did not designate critical habitat because we found that designation would be not prudent due to a danger of over-collection or purposeful harm or killing of snails if the locations of the snails were made public on critical habitat maps. On October 12, 1995, we finalized the Kanab ambersnail recovery plan (Service 1995, entire).                

                    We completed a 5-year review of the species' status in July 2011 (Service 2011, entire). As of the time of the 2011 5-year review, several genetic studies indicated that at least one of the three populations identified as the Kanab ambersnail was potentially part of a different species or subspecies, but we did not consider those studies alone to be certain enough to recommend delisting at that time (Miller                     *et al.*                     2000, p. 8; Stevens                     *et al.*                     2000, p. 7; Culver                     *et al.*                     2007, p. 3; Service 2011, pp. 8-9). The subsequent publication of a larger, more comprehensive study on the genetics of the Kanab ambersnail and the                     *Oxyloma*                     genus (Culver                     *et al.*                     2013, entire) resulted in our proposed rule to delist Kanab ambersnail based on new taxonomic information indicating that it was not a valid taxon, published in the                     **Federal Register**                     on January 6, 2020 (85 FR 487). Please refer to that proposed rule for a more detailed description of the Federal actions concerning this species that occurred prior to November 26, 2019.                

## Species Description and Habitat Information

                    It is our intent to discuss only those topics directly related to delisting the Kanab ambersnail in this rule. For more information on the description, biology, ecology, and habitat of the Kanab ambersnail, please refer to the final listing rule published in the                     **Federal Register**                     on April 17, 1992 (57 FR 13657); the Kanab ambersnail recovery plan (Service 1995); the most recent 5-year review for the Kanab ambersnail completed in July 2011 (Service 2011); or any of the documents referenced by this rule. The Service documents, personal communications, and a list of cited literature are available as supporting materials on                     *http://www.regulations.gov*                     under Docket No. FWS-R6-ES-2019-0055.                

                    The Kanab ambersnail (                    *Oxyloma haydeni kanabensis*) was taxonomically identified as a terrestrial snail in the family Succineidae. Succineids are usually referred to as ambersnails due to their mottled grayish-amber to yellowish-amber colored shells (Sorensen and Nelson 2002, p. 5).                

                    The Kanab ambersnail typically inhabits marshes and other wetlands watered by springs and seeps at the base of sandstone or limestone cliffs (Clarke 1991, pp. 28-29; Spamer and Bogan 1993, p. 296; Meretsky                     *et al.*                     2002, p. 309). Habitat vegetation can consist of cattail (                    *Typha domingensis*), sedge (                    *Juncus*                     spp.), native crimson monkeyflower (                    *Mimulus cardinalis*), watercress (                    *Nasturtium officinale*), native water sedge (                    *Carex aquatilis*), and maidenhair fern (                    *Adiantum capillus-veneris*) (57 FR 13657, April 17, 1992; Stevens                     *et al.*                     1997, p. 6; Sorensen 2005, p. 3). The Kanab ambersnail often inhabits dead and decaying litter and live stems of plants (Service 2011, p. 11).                

When the Kanab ambersnail was listed, we knew of two populations in Utah (Three Lakes and Kanab Creek Canyon) and one population in Arizona (Vasey's Paradise) (57 FR 13657, April 17, 1992). The Kanab Creek Canyon population in Utah was extirpated by 1991, after dewatering of the seep for livestock use severely reduced the available habitat. Kanab ambersnails were last found there in 1990, when three individuals were identified (Service 2011, p. 12). Currently, there are two naturally occurring populations of Kanab ambersnails (Vasey's Paradise in Arizona, and Three Lakes in Utah) and one introduced population (Upper Elves Canyon in Arizona) established with individuals translocated from Vasey's Paradise (Service 2011, p. 6).

                    The Vasey's Paradise population was discovered in 1991 (Spamer and Bogan 1993, p. 47). Vasey's Paradise is a riverside spring located approximately 33 miles (mi) (53 kilometers (km)) downstream of Lee's Ferry on the Colorado River, in Grand Canyon National Park, Arizona (Spamer and Bogan 1993, p. 37). Occupied and potential habitat at Vasey's Paradise is 9,041 square feet (ft2                    ) (840 square meters (m2                    )) (Service 1995, p. ii). The population is protected by National Park Service regulations and the presence of poison ivy, which deters visitors (Stevens                     *et al.*                     1997, p. 12; Sorensen 2016, pers. comm.).                

Monitoring of the Vasey's Paradise population from 2007 to present has relied on timed counts of live snails observed among the traditionally sampled vegetation patches. The timed count sampling provides a catch-per-unit-effort (CPUE) estimate of relative abundance of the snails in each survey. Over the past decade, there have been seasonal and annual variations in CPUE estimates of the Vasey's Paradise population. Overall the relative abundance of this Kanab ambersnail population has declined substantially from the levels observed in the late 1990s and prior to 2002, when drought conditions and reduced spring flow became particularly severe (Sorensen 2015, p. 10; Sorensen 2020,  p. 1). This decline has continued since 2011 (Sorensen 2015, p. 10; Sorensen 2020, p. 1).

                    The most recent population estimate is from 2002, which estimated 3,124 individuals and noted that population numbers could be highly variable from year to year (Gloss                     *et al.*                     2005, p. 3). Fourteen individuals were collected in 2008, for genetic analysis (Culver                     *et al.*                     2013, p. 7). A survey in 2016 found only one snail, but search conditions were difficult and time was limited (Sorensen 2016, pers. comm.).                

                    The Three Lakes population is a series of small ponds on private land approximately 6 mi (10 km) northwest of Kanab, Utah (Clarke 1991, p. 28; Service 1995, p. 3). Occupied and potential habitat is approximately 4.94 acres (ac) (2 hectares (ha)) (Service 1995, p. 3). Available habitat is wet meadow and marsh. The habitat was greatly reduced in size and the population declined beginning in 1991, due to preparations for anticipated development, which resulted in the original emergency listing (57 FR 13657, April 17, 1992). The development anticipated at the time of listing has not occurred, and Kanab ambersnails were found there in 2008 (Culver                     *et al.*                     2013, p. 6) and 2016 (Sorensen 2016, pers. comm.).                

A timed count survey of the Three Lakes population was conducted in early October 2011 by Service, Utah Division of Wildlife Resources, and Arizona Fish and Game Department biologists. The Three Lakes Kanab ambersnail population was robust with a CPUE estimate of 10.47 snails per 10 minutes searched (Sorensen 2011, p. 14). In 2016, the land was sold to Best Friends Animal Sanctuary, which has expressed a willingness to preserve the habitat. A followup survey of the Three Lakes Kanab ambersnail population was conducted by the same partners in early May 2017, with an estimated CPUE of 158.75 snails per 10 minutes searched (Sorensen 2017, pers. comm.).

                    Upper Elves Canyon is located approximately 83 mi (134 km) downstream of Vasey's Paradise on the Colorado River, in Grand Canyon National Park, Arizona (Sorensen 2016, p. 1). Occupied and potential habitat is adjacent to a perennial seep and is 1,068 ft2                     (99.2 m2                    ) (Sorensen 2005, p. 3). This population is protected by National Park Service regulations, as well as by its inaccessibility (Service 2011, p. 7). This population was established by the Arizona Fish and Game Department between 1998 and 2002, by                           ( print page 33139)                        translocating 340 individuals from the Vasey's Paradise population. Since 2005, this population has been considered self-sustaining with an estimated population of approximately 700 individuals (Sorensen 2005, p. 9). Between 2009 and 2015, timed count surveys of the translocated population at Upper Elves Chasm were conducted by Arizona Game and Fish Department, National Park Service biologists, and volunteers. Surveys over this timeframe documented a small but relatively stable Kanab ambersnail population at the site, with CPUE estimates between 0.85 to 4.15 snails per 10 minutes searched (Sorensen 2015, p. 12).                

## Taxonomy

                    Kanab ambersnails were first collected in 1909, by James Ferriss from an area called “The Greens,” a vegetated seep approximately 6 mi (10 km) north of Kanab in Kanab Creek Canyon, Utah (57 FR 13657, April 17, 1992; Service 1995, p. 2). However, ambersnails have not been found at the type locality since 1991 (Meretsky                     *et al.*                     2002, p. 314; Culver                     *et al.*                     2013, p. 6).                

                    The snails collected by James Ferriss in 1909 were initially placed in the species                     *Succinea hawkinisi,*                     but Pilsbry (1948, p. 797) placed them in                     *Oxyloma*                     and created the subspecies                     *kanabensis*                     under the species                     *haydeni*                     (57 FR 13657, April 17, 1992). The subspecies                     *kanabensis*                     classification was considered to be temporary at the time, and the author recommended that the taxonomic status be reconsidered in the future (Pilsbry 1948, p. 798; Clarke 1991, p. 23; 57 FR 13657, April 17, 1992).                

                    We have assessed all available genetic information for the Kanab ambersnail (Miller                     *et al.*                     2000, entire; Stevens                     *et al.*                     2000, entire; Culver                     *et al.*                     2013, entire). Since the listing of Kanab ambersnail in 1992 (57 FR 13657; April 17, 1992) and the publication of the Kanab ambersnail recovery plan in 1995 (Service 1995, entire), several studies on subspecies distribution, morphological characteristics, and genetic relationships to other                     *Oxyloma*                     species have been completed. We briefly describe these studies below. At this time, these studies represent the best scientific information available in order for us to analyze the Kanab ambersnail's distribution and taxonomic changes.                

Various analyses can be done to determine genetic structure of a species, including analyses of: (1) Mitochondrial DNA, which is rapidly evolving and useful to determine recent populations; (2) nuclear microsatellite DNA, which has high amounts of genetic variation and can be used to look at populations within a species; (3) nuclear DNA, which is inherited equally from both parents (unlike mitochondrial DNA, which is inherited maternally); and (4) amplified fragment length polymorphisms (AFLP), which are used to sample multiple loci across the genome.

                    Miller                     *et al.*                     (2000) used AFLP to determine intra- and inter-population genetic information for four                     *Oxyloma*                     species in Utah and Arizona. Among these, two Niobrara ambersnail (                    *Oxyloma haydeni haydeni*) locations were studied at Indian Gardens (Arizona) and Minus Nine Mile Spring (Arizona), and two Kanab ambersnail populations were studied at Three Lakes (Utah) and Vasey's Paradise (Arizona) (Miller                     *et al.*                     2000, pp. 1845-1946). From this study, the ambersnail population at Three Lakes appears more closely related to the Niobrara ambersnail population at Indian Gardens than to the ambersnail population at Vasey's Paradise (Miller                     *et al.*                     2000, p. 1852). Upper Elves Canyon was not included in this study.                

                    Stevens                     *et al.*                     (2000) used mitochondrial DNA and morphological analysis to distinguish Succineidae (                    *Oxyloma, Catinella,*                     and                     *Succinea*) populations in the United States and Canada. The authors collected over 450 samples from seven U.S. States and Canadian provinces, including from 63 different populations or locations of snails (Stevens                     *et al.*                     2000, p. 4). Determining                     *Oxyloma*                     species based on morphology was shown to be inaccurate (Stevens                     *et al.*                     2000, pp. 4-5, 42). Vasey's Paradise did not cluster with the Three Lakes ambersnail population or the two sampled Niobrara ambersnail populations, leading the authors to suggest Vasey's Paradise might represent a unique species (Stevens                     *et al.*                     2000, p. 41). However, a later, more comprehensive study found that Vasey's Paradise clustered closely enough with samples from other surrounding                     *Oxyloma*                     populations for them all to be considered part of the same                     *Oxyloma*                     species (Culver                     *et al.*                     2013, p. 57).                

                    In this most recent and detailed peer-reviewed study, ambersnails were collected from 12 locations in Arizona and Utah, with each location providing at least 14 ambersnail specimens (Culver                     *et al.*                     2013, p. 5). Samples consisted of Kanab ambersnail, Niobrara ambersnail, blunt ambersnail (                    *Oxyloma retusum*), undescribed species of                     *Oxyloma,*                     and individuals from                     *Catinella*                     (used to provide an outgroup comparison) (Culver                     *et al.*                     2013, p. 6). This study included samples from all three extant populations identified as Kanab ambersnail. Between the                     *Oxyloma*                     populations, shell morphology did not have the variation usually associated with different species, leading the authors to state that none of the 12 populations sampled was reproductively isolated from the others (Culver                     *et al.*                     2013, p. 52). This information supports the finding that the three populations identified as Kanab ambersnail do not alone comprise a discrete taxon.                

                    Genetic results indicated that there was gene flow among all the populations sampled, most likely due to short- or long-distance dispersals from other populations (Culver                     *et al.*                     2013, p. 57). Additionally, Kanab ambersnail samples from Vasey's Paradise did not cluster with the other two Kanab ambersnail populations (Culver                     *et al.*                     2013, pp. 51, 55). The authors concluded that the three populations of Kanab ambersnail are not a valid subspecies of                     *Oxyloma haydeni*                     and should instead be considered part of the same taxa as the ambersnails from the eight other populations of                     *Oxyloma*                     in Utah and Arizona that were sampled for comparison (Culver                     *et al.*                     2013, entire). This study declined to positively identify a species-level taxon for these 11 populations of ambersnail, due to lack of genetic information on the genus (Culver                     *et al.*                     2013). The primary author stated later that her expert opinion was they should all, including those previously identified as Kanab ambersnail, be considered Niobrara ambersnail (                    *Oxyloma hadenyi*) (Culver 2016, pers. comm.). The authors stated that specimens from the type locality of the Niobrara ambersnail in Nebraska could be examined for comparison to verify this conclusion (Franzen 1964, p. 73; Culver                     *et al.*                     2013, p. 57; Culver 2016, pers. comm.), but to date, no such analysis has been done.                

                    The above-described Culver                     *et al.*                     (2013) study was released as a United States Geological Survey (USGS) Scientific Investigations Report, and the review approach was similar to that of manuscripts published by scientific journals. The report was initially reviewed by five reviewers and required subsequent revision. The report received an additional review following revision due to the complex subject matter. The response to reviewer comments and subsequent revised manuscript were reviewed by another independent geneticist to ensure that the author adequately addressed issues and comments brought up by reviewers (Sorensen 2014, pers. comm.). The subsequent revision that occurred after 2011 resulted in more genetic information added to the final 2013 manuscript, which further substantiated                           ( print page 33140)                        the authors' findings (Sorensen 2014, pers. comm). As a result, we have a high level of confidence in the results of the Culver                     *et al.*                     (2013) genetic study.                

                    For the Kanab ambersnail to be considered a distinct subspecies, nuclear and mitochondrial DNA tests should show that the three populations cluster together when compared to other populations of ambersnails (Culver                     *et al.*                     2013, p. 55). However, the Vasey's Paradise population does not cluster with the other two Kanab ambersnail populations and the degree of variation shown in Vasey's Paradise from the other populations is not unique enough to constitute a subspecies on its own, as it shares markers with several nearby populations of non-listed                     *Oxyloma*                     snails (Stevens                     *et al.*                     2000, p. 41; Culver                     *et al.*                     2013, pp. 55-57).                

                    The genetic uniqueness in Vasey's Paradise may be attributable to flooding, which can erode away ideal vegetation or habitat, leaving only a few individuals able to survive and reestablish the population at that site, creating genetic bottlenecks. Genetic diversity at these types of sites will often be lower than at sites that have experienced short- or long-distance dispersals (Culver                     *et al.*                     2013, p. 55). Furthermore, ambersnails have the ability to self-reproduce, allowing for colonization of new areas by only one individual. This ability may explain how many genetically distinct populations of                     *Oxyloma*                     developed in a relatively short time period (Culver                     *et al.*                     2013, p. 56). At least one or more bottleneck events in the past, likely due to flooding, caused unusual population genetic events (Culver                     *et al.*                     2013, p. 55).                

                    Overall, these studies show that shell morphology and anatomical characteristics that were once considered diagnostic do not alone reliably correspond with the results from genetic analyses of Succineidae snails (Hoagland and Davis 1987, p. 519; Pigati                     *et al.*                     2010, p. 523). Samples originally identified as different species or subspecies based on physical differences are consistently found to be related closely enough to qualify as members of the same species based on genetic studies (Culver                     *et al.*                     2013, entire; Miller                     *et al.*                     2000, entire; Stevens                     *et al.*                     2000, entire). Traditionally, shell morphology, such as their slender and drawn-out spire and short shell aperture, was used to distinguish the Kanab ambersnail from other members of                     *Oxyloma*                     (Pilsbry 1948, pp. 797-798). However, shell shape can vary as much within a population as within a species (Hoagland and Davis 1987, p. 519). Therefore, it is important to consider other factors such as genetics, anatomy, and habitat to determine a species within                     *Oxyloma*                     (Hoagland and Davis 1987, p. 519; Sorensen and Nelson 2002, p. 5).                

                    In addition to shell morphology, reproductive anatomy (phallus shape) was previously a main determining factor of the                     *Oxyloma*                     genus (Miller                     *et al.*                     2000, p. 1853). However, anatomical descriptions used to classify the Kanab ambersnail had no quantifying factors, such as prostate gland length, and soft tissues were difficult to measure objectively (Pilsbry 1948, p. 798; Culver                     *et al.*                     2013, pp. 52-53). It is difficult to achieve standard anatomical measurements with repeatability because of the flexibility and elasticity of soft tissues (Culver                     *et al.*                     2013, p. 18). Overall, anatomical characteristics have been found to vary greatly within                     *Oxyloma*                     (Culver                     *et al.*                     2013, p. 52).                

                    There have been at least two instances when a species of snail was placed in the wrong genus due to relying solely on the reproductive anatomy (Johnson                     *et al.*                     1986, p. 105; Miller                     *et al.*                     2000, p. 1853). In another case, variation in anatomical structure was found in the blunt ambersnail, leading the authors to conclude that the species was not restricted geographically as initially believed (Franzen 1963, p. 94). Previous                     *Oxyloma*                     studies have used only one or two specimens to determine the species' taxonomic status, which makes it difficult to properly assess the true status (Hoagland and Davis 1987, p. 515).                

                    Standards for quantifying anatomy are minimal and not descriptive enough, with the use of such words as small, medium, and large, which are vague terms and not measurable (Hoagland and Davis 1987, p. 478). Anatomical characteristics should not be the only factor to determine a species within                     *Oxyloma,*                     even with an understanding of the individual and geographical variation (Franzen 1963, p. 83). Variation between populations, anatomical differences among individuals, overlapping habitat, and minimal repeatability with measurements of anatomical features make it difficult to rely on anatomical descriptions to determine species classification (Franzen 1964, p. 80; Sorensen and Nelson 2002, pp. 4-5). Overall, reproductive anatomy is likely not a good species indicator in snails; instead, genetic relationships provide the most reliable method of classifying taxa.                

                    In summary, these analyses present multiple interpretations of the taxonomy of the Kanab ambersnail, none of which correlates to that of our original listing. Although the exact taxonomy of the genus                     *Oxyloma*                     and its constituent species remains uncertain, it is clear that the populations designated as the Kanab ambersnail do not make up, together or separately, a valid subspecies. The 1992 final listing rule for the Kanab ambersnail (57 FR 13657; April 17, 1992) relied on the best available information at the time, and included only snails found in Vasey's Paradise in Arizona and Three Lakes and Kanab Creek in Utah. This situation has changed with the addition of the 2013 genetic study of the                     *Oxyloma*                     genus in Utah and Arizona (Culver                     *et al.*                     2013, entire).                

                    The various published and unpublished genetics reports described above offer different conclusions about how Succineid snails should be classified, particularly within the genus                     *Oxyloma.*                     However, none of the genetic studies provides support for                     *Oxyloma haydeni kanabensis*                     as a valid subspecies. Additionally, available genetic evidence suggests that at least one population identified as Kanab ambersnail is more closely related to other nearby                     *Oxyloma*                     populations than it is to the other two Kanab ambersnail populations.                

                    Therefore, we are delisting the Kanab ambersnail due to new taxonomic information that indicates that it is not a valid taxon, based on the best available science. The currently listed entity for the Kanab ambersnail, restricted to Vasey's Paradise and Upper Elves Canyon, Arizona, and Three Lakes, Utah, is not a valid taxonomic subspecies. We are unable to evaluate the populations identified as the Kanab ambersnail relative to the larger entity because the larger entity has not yet been defined from a taxonomic perspective. If we had additional updated information available about the taxonomy of the                     *Oxyloma*                     genus, we would conduct a status assessment of the larger entity, but in this case we do not have enough information to conduct that analysis. We do not consider the absence of information on the larger taxonomy of a group to be sufficient reason to keep an invalid subspecies listed as endangered.                

## Summary of Comments and Recommendations

                    In the proposed rule published in the                     **Federal Register**                     on January 6, 2020 (85 FR 487), we requested that all interested parties submit written comments on our proposal to delist the Kanab ambersnail by March 6, 2020. We also contacted appropriate Federal and State agencies, scientific experts and organizations, and other interested parties and invited them to comment on the proposal.                           ( print page 33141)                        Newspaper notices inviting general public comment were published in the Salt Lake Tribune and Saint George News. We did not receive any requests for a public hearing. All substantive information provided during the comment period was either incorporated directly into this final rule or is addressed below.                

### Peer Reviewer Comments

                    In accordance with our joint policy on peer review published in the                     **Federal Register**                     on July 1, 1994 (59 FR 34270) and our August 22, 2016 memorandum updating and clarifying the role of peer review of listing actions under the Act (USFWS 2016, entire), we solicited expert opinion from seven knowledgeable individuals with scientific expertise and familiarity with the Kanab ambersnail, its habitat, its taxonomy, its biological needs and potential threats, or principles of conservation biology. We received responses from five peer reviewers. The purpose of peer review is to ensure that our listing determinations are based on scientifically sound data, assumptions, and analyses.                

We reviewed and addressed all comments we received from the peer reviewers for substantive issues and new information regarding the proposed delisting of the Kanab ambersnail. The peer reviewers provided additional information, clarifications, and suggestions to improve the final rule, which we include in this rule or address in the responses to comments below. One of the reviewers expressed support for the proposed action. The other four did not state support or opposition to the proposed changes. All reviewers found that, with their suggested changes: The proposed rule was accurate; we provided adequate analysis to support our proposed determination; there were no significant oversights, omissions, or inconsistencies; our conclusions were logical and supported by the evidence provided; and we included all pertinent literature to support our arguments, assumptions, and conclusions.

                    All changes suggested by reviewers were incorporated into the text of this final rule. Such changes include additional details of population monitoring at all populations, an explanation of the rigorous review process for USGS reports, and a clarification on how shell morphology supports the conclusions in the Culver                     *et al.*                     2013 study. Other minor editorial clarifications and corrections were also made based on peer reviewer comments.                

### Public Comments

We received seven letters from the public that provided comments on the proposed rule. Two of the commenters expressed their support for the proposed delisting and corroborated information we supplied in the rule. Four commenters expressed their opposition to it. Of these four, none presented substantive information to support their opposition. In all cases, the opposition was based on the importance of protecting rare species and ecosystems. While we agree that protecting rare species and the habitats in which they occur is important, it is not a relevant factor in this determination because Kanab ambersnail is not a valid taxon and is being delisted on that basis.

One commenter provided some additional historical background regarding the naming and sampling of certain ambersnail sites mentioned in the proposed rule, but stated that this information did not affect the validity of the proposed action. We agree and thank the commenter for the additional detail and have added it to the record, but do not include it in our final rule as it does not impact our conclusions on taxonomy.

## Delisting Determination

Section 4 of the Act (16 U.S.C. 1533) and its implementing regulations (50 CFR part 424) set forth the procedures for listing, reclassifying, or removing species from the Federal Lists of Endangered and Threatened Wildlife and Plants. “Species” is defined by the Act as including any species or subspecies of fish or wildlife or plants, and any distinct population segment of vertebrate fish or wildlife that interbreeds when mature (16 U.S.C. 1532(16)). We may delist a species according to 50 CFR 424.11(e) if the best available scientific and commercial data indicate that: (1) The species is extinct; (2) the species does not meet the definition of an endangered or a threatened species; or (3) the listed entity does not meet the statutory definition of a species.

                    For the Kanab ambersnail, we conclude that the existing best available scientific information demonstrates that                     *Oxyloma haydeni kanabensis*                     does not represent a valid taxonomic entity and, therefore, does not meet the definition of “species” as defined in section 3(16) of the Act. Therefore,                     *Oxyloma haydeni kanabensis*                     no longer warrants listing under the Act. The Kanab ambersnail does not require a post-delisting monitoring plan because the requirements for a monitoring plan do not apply to species that are delisted for not meeting the statutory definition of a species.                

## Effects of This Rule

This rule revises 50 CFR 17.11(h) to remove the Kanab ambersnail from the Federal List of Endangered and Threatened Wildlife. Because no critical habitat was ever designated for this subspecies, this rule does not affect 50 CFR 17.95.

The prohibitions and conservation measures provided by the Act no longer apply to the snail previously identified as the Kanab ambersnail. Interstate commerce, import, and export of the snails previously identified as the Kanab ambersnail are not prohibited under the Act. In addition, Federal agencies are no longer required to consult under section 7 of the Act on actions that may affect the snails previously identified as Kanab ambersnail or their habitat.

## Required Determinations

### National Environmental Policy Act

                    We have determined that environmental assessments and environmental impact statements, as defined under the authority of the National Environmental Policy Act of 1969 (42 U.S.C. 4321*et seq.*), need not be prepared in connection with regulations pursuant to section 4(a) of the Act. We published a notice outlining our reasons for this determination in the                     **Federal Register**                     on October 25, 1983 (48 FR 49244).                

### Government-to-Government Relationship With Tribes

In accordance with the President's memorandum of April 29, 1994 (Government-to-Government Relations with Native American Tribal Governments; 59 FR 22951), Executive Order 13175 (Consultation and Coordination with Indian Tribal Governments), and the Department of the Interior's manual at 512 DM 2, we readily acknowledge our responsibility to communicate meaningfully with recognized Federal Tribes on a government-to-government basis. In accordance with Secretarial Order 3206 of June 5, 1997 (American Indian Tribal Rights, Federal-Tribal Trust Responsibilities, and the Endangered Species Act), we readily acknowledge our responsibilities to work directly with Tribes in developing programs for healthy ecosystems, to acknowledge that tribal lands are not subject to the same controls as Federal public lands, to remain sensitive to Indian culture, and to make information available to Tribes.

                    The populations that were listed as Kanab ambersnail do not occur on                           ( print page 33142)                        Tribal land. We have determined that while no Tribes will be directly affected by this action, the delisting may result in changes to the flow regime for the Colorado River in and adjacent to the Grand Canyon. Several Tribes have an historic affiliation with the Grand Canyon and could be affected by flow changes, should they occur. The potentially impacted Tribes are the Chemehuevi, the Colorado River Indian Tribes, the Hualapai, the Hopi, the Kaibab Band of Paiute, the San Carlos Apache, the San Juan Southern Paiute, the Navajo, and the Zuni. These Tribes were notified in advance of the publication of the proposed rule and have been informed of the finalization of the delisting.                

## References Cited

                    A complete list of all references cited in this rule is available on the internet at                     *http://www.regulations.gov*                     under Docket No. FWS-R6-ES-2019-0055 or upon request from the Utah Ecological Services Field Office (see                     **FOR FURTHER INFORMATION CONTACT**                    ).                

## Authors

The primary authors of this rule are staff members of the Service's Utah Ecological Services Field Office.

## Signing Authority

The Director, U.S. Fish and Wildlife Service, approved this document and authorized the undersigned to sign and submit the document to the Office of the Federal Register for publication electronically as an official document of the U.S. Fish and Wildlife Service. Martha Williams, Principal Deputy Director Exercising the Delegated Authority of the Director, U.S. Fish and Wildlife Service, approved this document on June 14, 2021, for publication.

# List of Subjects in 50 CFR Part 17

      - Endangered and threatened species
      - Exports
      - Imports
      - Reporting and recordkeeping requirements
      - Transportation

## Regulation Promulgation

Accordingly, we hereby amend part 17, subchapter B of chapter I, title 50 of the Code of Federal Regulations, as set forth below:

# PART 17—ENDANGERED AND THREATENED WILDLIFE AND PLANTS

1. The authority citation for part 17 continues to read as follows: 

Authority:16 U.S.C. 1361-1407; 1531-1544; and 4201-4245, unless otherwise noted.

§ 17.11

2. Amend § 17.11(h) by removing the entry for “Ambersnail, Kanab” under SNAILS from the List of Endangered and Threatened Wildlife. 

Anissa Craghead,

Acting Regulations and Policy Chief, Division of Policy, Economics, Risk Management, and Analytics, Joint Administrative Operations, U.S. Fish and Wildlife Service.

[FR Doc. 2021-13257 Filed 6-23-21; 8:45 am]

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