Endangered and Threatened Wildlife and Plants; Three Species Not Warranted for Listing as Endangered or Threatened Species

AGENCY:

Fish and Wildlife Service, Interior.

ACTION:

Notification of findings.

SUMMARY:

We, the U.S. Fish and Wildlife Service (Service), announce findings that three species are not warranted for listing as endangered or threatened species under the Endangered Species Act of 1973, as amended (Act). After a thorough review of the best available scientific and commercial information, we find that it is not warranted at this time to list the Kiamichi crayfish ( Faxonius saxatilis), Rio Grande chub ( Gila pandora), and Rio Grande sucker ( Pantosteus plebeius, formerly Catostomus plebeius). However, we ask the public to submit to us at any time any new information relevant to the status of any of the species mentioned above or their habitats.

DATES:

The findings in this document were made on June 20, 2024.

ADDRESSES:

Detailed descriptions of the bases for these findings are available on the internet at https://www.regulations.gov under the following docket numbers:

Those descriptions are also available by contacting the appropriate person as specified under FOR FURTHER INFORMATION CONTACT . Please submit any new information, materials, comments, or questions concerning this finding to the appropriate person, as specified under FOR FURTHER INFORMATION CONTACT .

FOR FURTHER INFORMATION CONTACT:

Individuals in the United States who are deaf, deafblind, hard of hearing, or have a speech disability may dial 711 (TTY, TDD, or TeleBraille) to access telecommunications relay services. Individuals outside the United States should use the relay services offered within their country to make international calls to the point-of-contact in the United States.

SUPPLEMENTARY INFORMATION:

Background

Under section 4(b)(3)(B) of the Act (16 U.S.C. 1531 et seq.), we are required to make a finding on whether or not a petitioned action is warranted within 12 months after receiving any petition that we have determined contains substantial scientific or commercial information indicating that the petitioned action may be warranted (“12-month finding”). We must make a finding that the petitioned action is: (1) Not warranted; (2) warranted; or (3) warranted, but precluded by other listing activity. We must publish a notification of these 12-month findings in the Federal Register .

Summary of Information Pertaining to the Five Factors

Section 4 of the Act (16 U.S.C. 1533) and the implementing regulations at part 424 of title 50 of the Code of Federal Regulations (50 CFR part 424) set forth procedures for adding species to, removing species from, or reclassifying species on the Lists of Endangered and Threatened Wildlife and Plants (Lists). The Act defines “species” as including any subspecies of fish or wildlife or plants, and any distinct population segment of any species of vertebrate fish or wildlife which interbreeds when mature. The Act defines “endangered species” as any species that is in danger of extinction throughout all or a significant portion of its range (16 U.S.C. 1532(6)), and “threatened species” as any species that is likely to become an endangered species within the foreseeable future throughout all or a significant portion of its range (16 U.S.C. 1532(20)). Under section 4(a)(1) of the Act, a species may be determined to be an endangered species or a threatened species because of any of the following five factors:

(A) The present or threatened destruction, modification, or curtailment of its habitat or range;

(B) Overutilization for commercial, recreational, scientific, or educational purposes;

(C) Disease or predation;

(D) The inadequacy of existing regulatory mechanisms; or

(E) Other natural or manmade factors affecting its continued existence.

These factors represent broad categories of natural or human-caused actions or conditions that could have an effect on a species' continued existence. In evaluating these actions and conditions, we look for those that may have a negative effect on individuals of the species, as well as other actions or conditions that may ameliorate any negative effects or may have positive effects.

We use the term “threat” to refer in general to actions or conditions that are known to or are reasonably likely to negatively affect individuals of a species. The term “threat” includes actions or conditions that have a direct impact on individuals (direct impacts), as well as those that affect individuals through alteration of their habitat or required resources (stressors). The term “threat” may encompass—either together or separately—the source of the action or condition or the action or condition itself. However, the mere identification of any threat(s) does not necessarily mean that the species meets the statutory definition of an “endangered species” or a “threatened species.” In determining whether a species meets either definition, we must evaluate all identified threats by considering the expected response by the species, and the effects of the threats—in light of those actions and conditions that will ameliorate the threats—on an individual, population, and species level. We evaluate each threat and its expected effects on the species, then analyze the cumulative effect of all of the threats on the species as a whole. We also consider the cumulative effect of the threats in light of those actions and conditions that will have positive effects on the species, such as any existing regulatory mechanisms or conservation efforts. The Secretary of the Interior determines whether the species meets the Act's definition of an “endangered species” or a “threatened species” only after conducting this cumulative analysis and describing the expected effect on the species now and in the foreseeable future.

The Act does not define the term “foreseeable future,” which appears in the statutory definition of “threatened species.” Our implementing regulations at 50 CFR 424.11(d) set forth a framework for evaluating the foreseeable future on a case-by-case basis, which is further described in the 2009 Memorandum Opinion on the foreseeable future from the Department of the Interior, Office of the Solicitor (M-37021, January 16, 2009; “M-Opinion,” available online at https://www.doi.gov/sites/doi.opengov.ibmcloud.com/files/uploads/M-37021.pdf ). The foreseeable future extends as far into the future as the U.S. Fish and Wildlife Service and National Marine Fisheries Service can make reasonably reliable predictions about the threats to the species and the species' responses to those threats. We need not identify the foreseeable future in terms of a specific period of time. We will describe the foreseeable future on a case-by-case basis, using the best available data and taking into account considerations such as the species' life-history characteristics, threat projection timeframes, and environmental variability. In other words, the foreseeable future is the period of time over which we can make reasonably reliable predictions. “Reliable” does not mean “certain”; it means sufficient to provide a reasonable degree of confidence in the prediction, in light of the conservation purposes of the Act.

In conducting our evaluation of the five factors provided in section 4(a)(1) of the Act to determine whether the Kiamichi crayfish, Rio Grande chub, and Rio Grande sucker meet the Act's definition of “endangered species” or “threatened species,” we considered and thoroughly evaluated the best scientific and commercial information available regarding the past, present, and future stressors and threats. We reviewed the petitions, information available in our files, and other available published and unpublished information for all of these species. Our evaluation may include information from recognized experts; Federal, State, and Tribal governments; academic institutions; foreign governments; private entities; and other members of the public.

In accordance with the regulations at 50 CFR 424.14(h)(2)(i), this document announces the not-warranted findings on petitions to list three species. We have also elected to include brief summaries of the analyses on which these findings are based. We provide the full analyses, including the reasons and data on which the findings are based, in the decisional file for each of the three actions included in this document. The following is a description of the documents containing these analyses:

The species assessment forms for the Kiamichi crayfish, Rio Grande chub, and Rio Grande sucker contain more detailed biological information, a thorough analysis of the listing factors, a list of literature cited, and an explanation of why we determined that these species do not meet the Act's definition of an “endangered species” or a “threatened species.” To inform our status reviews, we completed species status assessment (SSA) reports for these three species. Each SSA report contains a thorough review of the taxonomy, life history, ecology, current status, and projected future status for each species. This supporting information can be found on the internet at https://www.regulations.gov under the appropriate docket number (see ADDRESSES , above).

Kiamichi Crayfish

Previous Federal Actions

On June 18, 2007, we received a petition from Forest Guardians (now WildEarth Guardians) to list 475 species, including the Kiamichi crayfish ( Faxonius saxatilis; petitioned as Orconectes saxatilis), as an endangered or threatened species under the Act. On December 16, 2009, we published a 90-day finding (74 FR 66866) that the petition contained substantial information indicating that listing may be warranted for the Kiamichi crayfish. This document constitutes our 12-month finding on the June 18, 2007, petition to list the Kiamichi crayfish under the Act.

Summary of Finding

The Kiamichi crayfish is a small crayfish, olive-brown to reddish-brown dorsally and mostly whitish ventrally. It is distinguished morphologically from other crayfish species by details of its coloration and by structural features of sexually mature males. It also has been confirmed to be a distinct species through genetic analysis. The species was first described as Orconectes saxatilis, but, based on phylogenetic analyses, the genus name was changed in 2017 to Faxonius and that remains the currently accepted genus. The Kiamichi crayfish historically and currently inhabits the headwaters and larger tributaries of the upper Kiamichi River in southeastern Oklahoma. The species has been found only upstream of the community of Whitesboro in Le Flore County, Oklahoma.

The Kiamichi crayfish occurs in streams with substrate that is predominantly cobble, boulders, gravel, and other coarse rock. The species prefers riffle habitats but will shift to pool habitats during dry periods. The species needs stable riffles and pools, sufficient water quality, and sufficient water availability.

We have carefully assessed the best scientific and commercial information available regarding the past, present, and future threats to the Kiamichi crayfish, and we evaluated all relevant factors under the five listing factors, including any regulatory mechanisms and conservation measures addressing these threats. The primary threats to the Kiamichi crayfish include water quality degradation and increases in water temperatures. Water quality degradation caused by low pH levels and elevated levels of heavy metals may be partially natural, and conditions may be improving based on current trends. Currently, water temperatures are within suitable temperature ranges for stream crayfish species (26-27 degrees Celsius (°C) [78.8-80.6 degrees Fahrenheit (°F)] and support all life stages of the Kiamichi crayfish with no negative effects. However, future climate projections used in concert with established relationships between air temperature and water temperature indicate that water temperatures are likely to increase progressively in the future.

Currently, the species occupies four analysis units and the entire historical range. In general, streamflow does not differ significantly from historical conditions, and the majority of the Kiamichi crayfish range is on protected lands and is in a condition that supports resiliency of the species. The species has tolerated impaired water quality conditions for multiple decades, including lower pH levels and elevated heavy metals that may be at least partially natural. Currently, three analysis units are moderately resilient, and one is highly resilient, which we consider sufficient to provide redundancy for the species. In addition, the Kiamichi crayfish has sufficient representation because it has survived through periods of intensive logging and drought, has adapted to tolerate drought conditions, and has had no change in its range. Therefore, the threats appear to have low imminence and magnitude such that they are not currently having a significant effect on the species' current viability. Thus, after assessing the best available information, we conclude that the Kiamichi crayfish is not in danger of extinction throughout all of its range ( i.e., endangered).

Thus, we proceed with determining whether the species is likely to become endangered within the foreseeable future throughout all of its range ( i.e., threatened). In our projected timeframe of 50 years (2070), streamflow, landscape condition, pH and heavy metal levels are not expected to change significantly from the current condition in either of two scenarios that we evaluated. In fact, pH and heavy metal levels may improve for the Kiamichi crayfish in the future.

The primary threat considered to have a potentially significant effect on the Kiamichi crayfish is increased water temperatures due to climate change. Using processes set forth by the Intergovernmental Panel on Climate Change, we evaluated the Kiamichi crayfish under two future Representative Concentration Pathway (RCP) scenarios: Under scenario 1 (RCP 4.5), water temperatures do not rise to a level that would be negative for the species; under scenario 2 (RCP 8.5), summer water temperatures rise to levels that may negatively affect the Kiamichi crayfish periodically. However, potentially suboptimal water temperatures are projected to be periodic during summer months only, and the species is adapted to periods of drought and higher temperatures. Because the Kiamichi crayfish has the ability to tolerate drought and higher temperatures by burrowing and moving to pools, the species is expected to be able to tolerate these times of higher projected water temperatures. Overall increasing water temperatures may affect the species in the future, but each analysis unit will remain in the same overall resiliency condition as the current condition because of the species' ability to modify behavior. Therefore, we anticipate redundancy and representation to remain similar to current conditions into the future. After assessing the best available information, we conclude that the Kiamichi crayfish is not likely to become endangered within the foreseeable future throughout all of its range.

We also evaluated whether the Kiamichi crayfish is endangered or threatened in a significant portion of its range. We did not find any portions of the Kiamichi crayfish's range for which both (1) the portion is significant, and (2) the species is in danger of extinction in that portion, either now or within the foreseeable future. Thus, after assessing the best available information, we conclude that the Kiamichi crayfish is not in danger of extinction in a significant portion of its range now, or within the foreseeable future.

After assessing the best available information, we conclude that the Kiamichi crayfish is not in danger of extinction or likely to become in danger of extinction throughout all of its range or in any significant portion of its range. Therefore, we find that listing the Kiamichi crayfish as an endangered species or threatened species under the Act is not warranted. A detailed discussion of the basis for this finding can be found in the species assessment form and other supporting documents, which are available on https://www.regulations.gov under docket number FWS-R2-ES-2023-0258.

Peer Review

In accordance with our July 1, 1994, peer review policy (59 FR 34270; July 1, 1994) and the Service's August 22, 2016, Director's Memo on the Peer Review Process, we solicited independent scientific reviews of the information contained in the Kiamichi crayfish SSA report. The Service sent the SSA report to six independent peer reviewers and received three responses. Results of this structured peer review process can be found at https://www.regulations.gov under docket number FWS-R2-ES-2023-0258. We incorporated the results of these reviews, as appropriate, into the SSA report, which is the foundation for this finding.

Rio Grande Chub

Previous Federal Actions

On September 27, 2013, we received a petition from WildEarth Guardians to list the Rio Grande chub ( Gila Pandora) as an endangered or threatened species under the Act and designate critical habitat. On March 6, 2016, we published a 90-day finding (81 FR 14058) that the petition contained substantial information indicating that listing may be warranted for the Rio Grande chub. This document constitutes our 12-month finding on the September 27, 2013, petition to list the Rio Grande chub under the Act.

Summary of Finding

The Rio Grande chub is a small freshwater fish found predominantly in montane stream environments in the upper Rio Grande basin in north-central New Mexico and south-central Colorado. Its range also includes portions of the Canadian River basin in New Mexico and the Pecos River basin in New Mexico and Texas. Another population may exist in the State of Coahuila, Mexico. The Rio Grande chub now occupies a small portion of its historical range in fragmented populations.

Found in a variety of aquatic habitats, the Rio Grande chub is associated with low gradient streams that may experience substantial variation in annual environmental conditions. Streams occupied by this species tend to have low to moderate water flow, low water depths, and a large temperature range. Like other chub species, the Rio Grande chub is often associated with instream structures. As omnivorous mid-water column feeders, the Rio Grande chub consumes drifting invertebrates, fish, and occasional vegetation.

We have carefully assessed the best scientific and commercial information available regarding the past, present, and future threats to the Rio Grande chub, and we evaluated all relevant factors under the five listing factors, including any regulatory mechanisms and conservation measures addressing these threats. The primary threats affecting the Rio Grande chub's biological status include predation and competition from nonnative species, habitat loss and fragmentation caused by altered hydrology, catastrophic wildfire, and changes in environmental conditions due to climate change.

We estimated the risk of extirpation for each Rio Grande chub population over several time frames. The threats we considered include catastrophic wildfire, nonnative species, and water withdrawal due to surface water diversion and/or groundwater pumping. There were three categories of risk: high, medium, and low. These categories were defined by the likelihood of the threat occurring and the magnitude of its impact on the population. High risk meant the threat was likely ( i.e., greater than 50 percent) to occur over the given timeframe and the magnitude to the population was severe, potentially resulting in extirpation. Low risk meant a threat had a remote probability ( i.e., less than 10 percent) of occurring and the magnitude would be minimal. For medium risk populations, either the threat was unlikely ( i.e., less than 50 percent) to occur or the magnitude of impact was projected to be moderate, meaning there could be population declines but total extirpation was unlikely. First, we assessed the risk of extirpation for each population over the next 10 years based on the current habitat and demographic characteristics of each population. Since conditions are expected to change in the future, we next considered two future time steps: mid-century ( i.e., 2050) and late-century ( i.e., 2099). These projections incorporated the effects of changes in environmental conditions under two climate change scenarios.

There are 53 populations of Rio Grande chub in the United States, which combined occupy 844 kilometers (km) (524.4 miles (mi)) of stream length. About 34 percent of these populations are at high risk of extirpation over the next 10 years. Most populations (57 percent) are at a medium risk of extirpation, with only 9 percent of populations at low risk. This risk of extirpation was primarily driven by nonnative species. No populations were at risk of extirpation due to stream dewatering and none were at high risk of extirpation due to wildfire over the next 10 years. Threats appear to have low imminence and magnitude such that they are not currently having a significant effect on the species' current viability. These 53 populations are distributed across a wide geographic area, providing redundancy from catastrophic events. They also occur across a range of environmental gradients, indicating the retention of adaptive capacity ( i.e., representation). Thus, after assessing the best available information, we conclude that the Rio Grande chub is not in danger of extinction throughout all of its range ( i.e., endangered).

We then assessed whether extirpation risk as well as resiliency, redundancy, and representation would change over time. For resiliency, we modelled future changes in habitat suitability under two future Representative Concentration Pathway (RCP) scenarios: RCP4.5 and RCP8.5. Then we incorporated these changes in our estimation of future risk of extirpation for each population. Although the general trend was a decrease in habitat suitability over time, most populations (75 percent) are projected to have no changes in resiliency. There was little projected change in extirpation risk by mid- and late-century. Most populations continue to be at medium risk of extirpation, although the risks posed by wildfire did increase over time for some populations. Although changes in redundancy and representation are anticipated should high risk populations be extirpated, the low and moderate risk populations will continue to be distributed across the species range, conferring redundancy and representation. After assessing the best available information, we conclude that the species is not likely to become endangered within the foreseeable future throughout all of its range.

We also evaluated whether the Rio Grande chub is endangered or threatened in a significant portion of its range. We did not find any portions of the Rio Grande chub's range for which both (1) the portion is significant, and (2) the species is in danger of extinction in that portion, either now or within the foreseeable future. Thus, after assessing the best available information, we conclude that the Rio Grande chub is not in danger of extinction in a significant portion of its range now, or within the foreseeable future. After assessing the best available information, we conclude that the Rio Grande chub is not in danger of extinction or likely to become in danger of extinction throughout all of its range or in any significant portion of its range. Therefore, we find that listing the Rio Grande chub as an endangered species or threatened species under the Act is not warranted. A detailed discussion of the basis for this finding can be found in the Rio Grande chub species assessment form and other supporting documents on https://www.regulations.gov under Docket No. FWS-R2-ES-2024-0081 (see ADDRESSES , above).

Peer Review

In accordance with our July 1, 1994, peer review policy (59 FR 34270; July 1, 1994) and the Service's August 22, 2016, Director's Memo on the Peer Review Process, we solicited independent scientific reviews of the information contained in the Rio Grande chub SSA report. The Service sent the SSA report to four independent peer reviewers and received four responses. Results of this structured peer review process can be found at https://www.regulations.gov under Docket No. FWS-R2-ES-2024-0081. We incorporated the results of these reviews, as appropriate, into the SSA report, which is the foundation for this finding.

Rio Grande Sucker

Previous Federal Actions

On October 3, 2014, we received a petition from WildEarth Guardians to list the Rio Grande sucker ( Pantosteus plebeius; petitioned as Catostomus plebeius) as an endangered or threatened species under the Act and designate critical habitat. The species was originally described under the genus Catostomus, but has since been reclassified under the genus Pantosteus. On March 16, 2016, we published a 90-day finding (81 FR 14058) that the petition contained substantial information indicating that listing may be warranted for the Rio Grande sucker. This document constitutes our 12-month finding on the October 3, 2014 petition to list the Rio Grande sucker under the Act.

Summary of Finding

The Rio Grande sucker is a small freshwater fish found predominantly in montane stream environments in the upper Rio Grande basin in north-central New Mexico and south-central Colorado. Its historical range in the United States also includes portions of the Gila, Pecos, and Mimbres Rivers basins. The described range of the Rio Grande sucker also extends into several drainage basins in northern Chihuahua, Mexico.

Found in a variety of aquatic habitats, the Rio Grande sucker is associated with low gradient streams that may experience substantial variation in environmental conditions annually. Streams occupied by this species tend to have low to moderate water flow, low water depths, and a large temperature range. As a benthic feeder, this species is often found in areas with cobble and gravel substrates that support algal growth.

We have carefully assessed the best scientific and commercial information available regarding the past, present, and future threats to the Rio Grande sucker, and we evaluated all relevant factors under the five listing factors, including any regulatory mechanisms and conservation measures addressing these threats. The primary threats affecting the Rio Grande sucker's biological status include predation and competition from nonnative species, habitat loss and fragmentation caused by altered hydrology, catastrophic wildfire, and changes in environmental conditions due to climate change.

We estimated the risk of extirpation for each Rio Grande sucker population over several time frames. The threats we considered include catastrophic wildfire, nonnative species, and water withdrawal due to surface water diversion and/or groundwater pumping. We first assessed the risk of extirpation for each population over the next 10 years based on the current demographic and habitat conditions of each population. Since conditions are expected to change in the future, we next considered two future time steps: mid-century ( i.e., 2050) and late-century ( i.e., 2099). These projections incorporated the effects of changes in environmental conditions under two climate change scenarios.

There are currently 32 populations of Rio Grande sucker in the United States, which combined occupy 605.7 km (376.4 mi) of stream length. About 38 percent of these populations are at high risk of extirpation over the next 10 years. Most populations (56 percent) are at a medium risk of extirpation, with 6 percent at low risk. The risk of extirpation was primarily driven by nonnative species. Over the next 10 years, two populations were at risk of extirpation due to stream dewatering and none were at high risk of extirpation due to wildfire. There was little projected change in risk by mid- and late-century. Most populations continue to be at medium risk of extirpation, although the risks posed by wildfire did increase over time for some populations. Levels of risk were mostly consistent across the range of the species: across drainages basins, most populations were at an overall medium risk of extirpation across time steps and scenarios. Threats appear to have low imminence and magnitude such that they are not currently having a significant effect on the species' current viability. These 32 populations are distributed across a wide geographic area, providing redundancy from catastrophic events. They also occur across a range of environmental gradients, indicating the retention of adaptive capacity ( i.e., representation). Populations also occur in Mexico and there is suitable habitat present in basins where it has been found. Thus, after assessing the best available information, we conclude that the Rio Grande sucker is not in danger of extinction throughout all of its range ( i.e., endangered).

We then assessed whether extirpation risk as well as resiliency, redundancy, and representation would change over time. To inform future resiliency, we modelled future changes in habitat suitability under two future RCP scenarios: RCP4.5 and RCP8.5. Then we incorporated these changes in our estimation of future risk of extirpation for each population. Although the general trend was a decrease in habitat suitability over time, most populations (69 percent) are projected to have no changes in resiliency. Similar patterns of habitat change were projected for portions of the range in Mexico. Although changes in redundancy and representation are anticipated should high risk populations be extirpated, the low and moderate risk populations will continue to be distributed across the species range, conferring redundancy and representation. After assessing the best available information, we conclude that the species is not likely to become endangered within the foreseeable future throughout all of its range.

We also evaluated whether the Rio Grande sucker is endangered or threatened in a significant portion of its range. We did not find any portions of the Rio Grande sucker's range for which both (1) the portion is significant, and (2) the species is in danger of extinction in that portion, either now or within the foreseeable future. Thus, after assessing the best available information, we conclude that the Rio Grande sucker is not in danger of extinction in a significant portion of its range now, or within the foreseeable future.

After assessing the best available information, we concluded that the Rio Grande sucker is not in danger of extinction or likely to become in danger of extinction throughout all of its range or in any significant portion of its range. Therefore, we find that listing the Rio Grande sucker as an endangered species or threatened species under the Act is not warranted. A detailed discussion of the basis for this finding can be found in the Rio Grande sucker species assessment form and other supporting documents on https://www.regulations.gov under Docket No. FWS-R2-ES-2024-0082 (see ADDRESSES , above).

Peer Review

In accordance with our July 1, 1994, peer review policy (59 FR 34270; July 1, 1994) and the Service's August 22, 2016, Director's Memo on the Peer Review Process we solicited independent scientific reviews of the information contained in the Rio Grande sucker SSA report. The Service sent the SSA report to four independent peer reviewers and received four responses. Results of this structured peer review process can be found at https://www.regulations.gov under Docket No. FWS-R2-ES-2024-0082. We incorporated the results of these reviews, as appropriate, into the SSA Report, which is the foundation for this finding.

New Information

We request that you submit any new information concerning the taxonomy of, biology of, ecology of, status of, or stressors to the Kiamichi crayfish, Rio Grande chub, or Rio Grande sucker to the appropriate person, as specified under FOR FURTHER INFORMATION CONTACT , whenever it becomes available. New information will help us monitor these species and make appropriate decisions about their conservation and status. We encourage local agencies and stakeholders to continue cooperative monitoring and conservation efforts.

References

A complete list of the references used in these petition findings is available in the relevant species assessment form, which is available on the internet at https://www.regulations.gov in the appropriate docket (see ADDRESSES , above) and upon request from the appropriate person (see FOR FURTHER INFORMATION CONTACT , above).

Authors

The primary authors of this document are the staff members of the Species Assessment Team, Ecological Services Program.

Authority

The authority for this action is section 4 of the Endangered Species Act of 1973, as amended (16 U.S.C. 1531 et seq.).