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Grotto Sculpin

Questions and Answers - Proposal to List the Grotto Sculpin as Endangered and Designate Critical Habitat

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What action is the Service taking?

grotto sculpin

The grotto sculpin is a small, cave-dwelling fish found only in Perry County, Missouri.

Photo by Missouri Department of Conservation; Brad Probst

The Service is proposing to list the grotto sculpin as endangered and to designate critical habitat under the authority of the Endangered Species Act.  To propose listing this fish as endangered and designate critical habitat, the Service published a “proposed rule” in the Federal Register on September 27, 2012.  The proposed rule opens a 60-day public comment period, which closes on November 26, 2012.  Before making a final decision on the listing and critical habitat proposal, the Service must gather and analyze the public comments and new information received during the public comment period.


Where is the grotto sculpin found?
The grotto sculpin is restricted to five cave systems and two surface streams in Perry County, Missouri. 


Why is the Service proposing to list the grotto sculpin as endangered?

The Perry County karst plain is characterized by thousands of sinkholes and over 700 caves. Water quality in karst is vulnerable to pollution because contaminated water can flow rapidly from the surface to below-ground aquifers and cave streams.  Sinkholes that have been modified to drain adjacent land further increase the potential for contamination because run-off enters underground streams without the benefit of being filtered through vegetated buffers or substrates unless Best Management Practices used around sinkholes can reduce runoff of contaminants.  Water pollution not only harms the grotto sculpin but also the cave stream ecosystems and aquifer underlying the Perry County karst plain.


The grotto sculpin is endemic to one karst system in Perry County.  Historical population numbers are unknown, but two mass mortality events have occurred since the early 2000s.  Evidence indicates that both events were caused by point-source pollution of above-ground waters that drained to underground aquatic habitats.  With the small size and range of the grotto sculpin population, extinction is likely if measures are not taken to improve water quality within the watershed that feeds grotto sculpin streams.


What is critical habitat?

Critical habitat is a tool within the Endangered Species Act that identifies areas that are important to the conservation of a listed species. Within areas that are designated as critical habitat, federal agencies are required to do a special review of activities that they intend to carry out, fund, or permit. Their activities cannot destroy or adversely modify the important components of critical habitat. However, a critical habitat designation does not affect actions that do not involve a federal agency.  For example, the designation of critical habitat does not affect a landowner undertaking a project on private land that does not involve federal funding or require a federal permit or authorization.


Why is the Service proposing to designate critical habitat for the grotto sculpin?
The Endangered Species Act requires the Service to designate critical habitat "to the maximum extent prudent" when a species is added to the list of Endangered and Threatened Wildlife and Plants.  Designation of critical habitat can help focus conservation activities for a listed species by identifying areas that are essential for the conservation of that species. Also, designation of critical habitat alerts the public as well as land-managing agencies to the importance of these areas, but the Endangered Species Act only imposes additional restrictions on the actions of federal agencies.


What areas are proposed as critical habitat for the grotto sculpin?

A map of the proposed critical habitat is shown on the bottom of this page.  We are proposing four units that include 36.28 square miles of underground aquatic habitat in recharge areas plus 19.2 miles of surface stream as critical habitat for the grotto sculpin.The first unit encompasses all below-ground aquatic habitat within the recharge areas of the Moore Cave System, the Crevice Cave System, Ball Mill Spring, and Keyhole Spring.  The second unit encompasses all below-ground aquatic habitat within the recharge areas of Mystery Cave, Rimstone River Cave, Running Bull Cave, and Thunderhole Resurgence.  The third unit includes 4 miles of Blue Spring Branch from its emergence within the Moore Cave System to its confluence with Bois Brule Creek.  The fourth unit includes 15.2 miles of Cinque Hommes Creek from its emergence near Mystery Cave and Resurgence to its confluence with Bois Brule Creek. 


Although the exact extent of habitat occupied by grotto sculpin within the recharge areas is not known due to the inaccessibility of underground karst, we presume all aquatic habitats within the entire 36.28 square mile recharge area could reasonably be expected to be occupied.  The delineated boundaries of critical habitat for Units One and Two within cave and resurgence recharge zones apply only to aquatic habitat.


Was there an economic analysis of the impact of the proposed critical habitat designation?

The Endangered Species Act requires that we take into account the economic and other relevant impacts of specifying any particular area as critical habitat.  An economic analysis has not been conducted yet but will be in the future for the proposed grotto sculpin critical habitat.  A draft of the economic analysis will be available for public review and comment before a decision to designate critical habitat is made.  The economic analysis and public comments on that analysis will be included in the information considered when making the final decision on whether to designate critical habitat and the exact extent of that designation.


Would listing the grotto sculpin as endangered or designating critical habitat affect use of
personal property? 

If the grotto sculpin is listed as endangered, it will be illegal to “take” a grotto sculpin without a permit.  Take is defined to include harass, harm, hunt, shoot, wound, kill, trap, capture, or collect, or attempt to engage in any such conduct.  Activities that harm the water quality of grotto sculpin habitat could be violations of the Endangered Species Act.  Many of these activities are currently illegal under existing state law.  We envision working with local and state agencies to improve compliance with existing water quality regulations by implementing Best Management Practices that specifically address sinkholes.


Critical habitat does not require landowners to carry out any special management actions or restrict the use of the land.  Nor does the designation mean the government intends to acquire or control the land.  Designated critical habitat is protected by requiring that any actions a federal agency authorizes, funds, or carries out do not “adversely modify” critical habitat. Therefore, activities on private lands that do not require federal permits or funding are not affected by a critical habitat designation. 


If a landowner applies for a federal permit or federal funding, the federal agency responsible would consult with the Service to determine how the action may affect the grotto sculpin or its designated critical habitat.  If such actions would affect the grotto sculpin, we would work with all interested parties to minimize or avoid adverse effects.


How do I comment on the proposal to list the grotto sculpin and designate critical habitat?

You may submit comments by one of the following methods:



Go to the Federal eRulemaking Portal: http://www.regulations.gov.  In the Search box, enter Docket No. FWS–R3–ES–2012–0065, which is the docket number for this rulemaking.  Then, click the Search button.  You may submit a comment by clicking on “Comment Now!”  If your comments will fit in the provided comment box, please use this feature of http://www.regulations.gov, as it is most compatible with our comment review procedures.  If you attach your comments as a separate document, our preferred file format is Microsoft Word.  If you attach multiple comments (such as form letters), our preferred format is a spreadsheet in Microsoft Excel.


By hard copy

Submit by U.S. mail or hand-delivery to: 
Public Comments Processing
Attn: FWS–R3–ES–2012–0065
Division of Policy and Directives Management
U.S. Fish and Wildlife Service
4401 N. Fairfax Drive, MS 2042–PDM
Arlington, VA 22203.


We will not accept comments by e-mail or fax.  The comment period closes on November 26, 2012.


How can I get more information?
The Service will host a public meeting to provide information on the proposed listing at the Higher Education Center in Perryville, 108 South Progress Drive, Perryville, Missouri on October 30, 2012 from 5:00-8:00 PM.  The meeting will include information about the grotto sculpin and the Service’s proposal, and opportunity for the public to ask questions of Service biologists.


Information about the grotto sculpin and the proposed listing as endangered and designation of critical habitat is available on our website at http://www.fws.gov/midwest/endangered.


You may also write or phone:


Amy Salveter, Field Supervisor
U.S. Fish and Wildlife Service
Columbia Missouri Ecological Services Field Office
101 Park De Ville Drive, Suite A
Columbia, MO 65203
Telephone 573-234-2132



Map of proposed Critical Habitat for the grotto sculpin.


Map of proposed critical habitat for the grotto sculpin.


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Last updated: March 12, 2018