PALLID STURGEON coRE VERYPMN Recovery Plan for the Pallid Sturgeon (Scaphirhynchus a/bus) Prepared by the Pallid Sturgeon Recovery Team Principal Authors Mark P. Dryer, Leader U.S. Fish and Wildlife Service Ecological Services 1500 Capitol Avenue Bismarck, ND 58501 and Alan J. Sandvol U.S. Fish and Wildlife Service Fisheries and Federal Aid 1500 Capitol Avenue Bismarck, ND 58501 for Region 6 U.S. Fish and Wildlife Service Denver, Colorado / Approved: Re~5l i rector Date TABLE OF CONTENTS TITLE PAGE RECOVERY BACKGROUND AND STRATEGY iii PALLID STURGEON RECOVERY TEAM iv DISCLAIMER V ACKNOWLEDGEMENTS vi EXECUTIVE SUMMARY vii Part I INTRODUCTION 1 History 1 General Description 1 Historical Distribution and Abundance 3 Present Distribution and Abundance 5 Habitat Preference 5 Current Velocity 7 Turbidity 8 Water Depth 8 Substrate 8 Temperature 8 Life History 8 Reproductive Biology 8 Food and Feeding Habits 9 Age and Growth 10 Reasons for Decline 10 Habitat Loss 10 Commercial Harvest 13 Pall uti on/Contami nants 14 Hybridization 14 Part II RECOVERY 16 Recovery Objectives and Criteria 16 Recovery—Priority Management Areas 16 Recovery Outline 19 24 Recovery Outline Narrative . LITERATURE CITED 42 Part III IMPLEMENTATION SCHEDULE 46 FIGURES NO. PAGE 1. Comparative Diagrams of the Ventral Surface of the Head of Shovelnose Sturgeon and Pallid Sturgeon, Showing Several Measurement Ratios of Value for Identification 2 2. Historic Range of Pallid Sturgeon 4 3. Recent Occurrence of Pallid Sturgeon 6 4. Recovery—Priority Management Areas 18 RECOVERY BACKGROUND AND STRATEGY The pallid sturgeon (Scaphirhynchus albus Forbes and Richardson) was listed as an endangered species on September 6, 1990 (55 FR 36641) pursuant to the Endangered Species Act (Act) of 1973 (16 U.S.C. 1531 et seq.) as amended. The range of the pallid sturgeon overlays three U.S. Fish and Wildlife Service (Service) Regions: Region 3, Region 4, and Region 6, with Region 6 having been designated the lead Region for recovery (research functions are provided to all Service Regions by Region 8). Because of the wide range of the pallid sturgeon, its believed extreme rarity, numerous threats to species survival, and paucity of information on species life history and habitats, an eight—member, multi—disciplinary recovery team was established to develop this Pallid Sturgeon Recovery Plan (Recovery Plan). In development of the Recovery Plan, the recovery team utilized the expertise of other sturgeon researchers and managers and published literature. The Introduction section, Part I, of this Recovery Plan describes the distribution, status, life history, and habitat—association information that is known about the pallid sturgeon. Reasons for listing and threats to the species are also described. The Recovery section, Part II, provides the short— and long—term recovery objectives and actions needed to achieve recovery. Recovery tasks, which can be independently funded and carried out, are described for each action. The Implementation Schedule, Part III, of the Recovery Plan is essentially a summary table that indicates task priorities, task descriptions, duration of tasks, the agency or entity with the responsibility or administrative authority to fund or carry out the task, and lastly, estimated costs. Al] priority 1 tasks are listed first, followed by priority 2 and priority 3 tasks. Because of the immediacy for implementation of recovery actions to prevent extinction of the species, most tasks are assigned priority 1. This Recovery Plan is subject to modification as needed by new findings, changes in species status, and the completion of recovery tasks. iii PALLID STURGEON RECOVERY TEAM Team Members Mark Dryer Pat Clancey Team Leader Montana, Dept. of Fish, U.S. Fish and Wildlife Service Wildlife and Parks Ecological Services P.O. Box 1336 1500 E. Capitol Avenue 125 Ennis Street Bismarck, ND 58501 Ennis, MT 59729 Mark Harberg James Riis U.S. Army Corps of Engineers South Dakota Game, Fish and Missouri River Division Parks Department P.O. Box 103, Downtown Station 523 E. Capitol Omaha, NE 68101—0103 Pierre, SD 57101 Dr. Frank Chapman Kim Graham University of Florida Fish and Wildlife Research Dept. of Fisheries and Center Aquacul ture Missouri Dept. of Conservation 7922 NW. 71st Street 1110 South College Avenue Gainesville, FL 32606 Columbia, MO 65201 Bobby Reed Al Sandvol Louisiana Dept. of Wildlife U.S. Fish and Wildlife Service and Fisheries Fish and Wildlife Assistance 1213 N. Lakeshore Drive Office Lake Charles, LA 70601 1500 E. Capitol Avenue Bismarck, ND 58501 Team Consultant Dr. Kent Keenlyne U.S. Fish and Wildlife Service 420 South Garfield Pierre, SD 57501 iv DISCLAIMER Recovery plans delineate reasonable actions that are believed to be required to recover and/or protect the species. Plans are prepared by the U.S. Fish and Wildlife Service with the assistance of recovery teams, contractors, State agencies, and others. Objectives will only be attained and funds expended contingent upon appropriations, priorities, and other budgetary constraints. Recovery plans do not necessarily represent the views or the official positions or approvals of individuals or agencies involved in the plan formulation, other than the U.S. Fish and Wildlife Service. They represent the official position of the U.S. Fish and Wildlife Service only after they have been signed by the Regional Director or Director as apDroved Literature Citation should read as follows: U.S. Fish and Wildlife Service. 1993. Pallid Sturgeon Recovery Plan. U.S. Fish and Wildlife Service, Bismarck, North Dakota. 55 pp. v . ACKNOWLEDGEMENTS The Pallid Sturgeon Recovery Plan was prepared by the U.S. Fish and Wildlife Service in collaboration with the Pallid Sturgeon Recovery Team. The following people are gratefully acknowledged for providing comments on previous drafts of the Recovery Plan. W. Bailey G. Fritz L. Jones J. Phelps J. Bloomquist D. Fruge L. Kallemeyn D. Pope H. Bollig D. Galat K. Keenlyne G. Power K. Bouce T. Gengerke J. Kramer J. Presley D. Broadbent J. Graves D. Latka D. Scarnecchia M. Carlson T. Graves H. Manig J. Schaufelberger J. Christian M. Gutzmer R. McPhail C. Smith M. Conlin J. Hamill J. Medlin C. Stalnaker J. Crance S. Hamilton G. Miller C. Stone J. Dwyer J. Hanchey T. Mosher D. Taylor S. Filipek D. Hansen W. Neal D. Unkenholz D. Flemming D. Harms F. Parauka R. Wallem B. Fontenot L. Hesse T. Parks J. Wedeward R. Fortney C. Hunter L. Peterman E. Wick A. Foster C. Johnson W. Pflieger P. Worthing S. Zschomler S. Schweigert, D. Licht, and S. Werdon provided word processing services and graphics expertise. vi EXECUTIVE SUMMARY Current SDecies Status: The pallid sturgeon was listed as endangered on September 6, 1990 (55 FR 36641). Although the species range is large, catch records are extremely rare. The species may be close to extinction. Habitat Reauirements and Limitina Factors: The pallid sturgeon is native to the Missouri and Mississippi Rivers and, therefore, adapted to the pre— development habitat conditions that existed in these large rivers. These conditions generally can be described as large, free—flowing, warmwater, turbid habitat with a diverse assemblage of physical habitats that were in a constant state of change. Modification of the pallid sturgeon’s habitat by human activities has blocked fish movement, destroyed or altered spawning areas, reduced food sources or ability to obtain food, altered water temperatures, reduced turbidity, and changed the hydrograph of the river system. Overfishing, pollution, and hybridization that occurs due to habitat alterations also have probably contributed to the species’ population decline. RecoverY Objectives and Criteria: The short—term recovery objective is to prevent species extinction by establishing three captive broodstock populations in separate hatcheries that are initially composed of five to seven wild adult males and five to seven wild adult females each by 1998. The long—term objective is to downlist and delist the species through protection, habitat restoration, and propagation activities by 2040. Downlisting and delisting would be initiated when pallid sturgeon are reproducing naturally and populations are self—sustaining within designated river reaches. Delisting criteria are undeterminable at this time. Preliminary downlisting criteria have been identified, however these criteria may be modified or expanded in the future. Under the current preliminary criteria, downlisting may be considered when (1) a population structure with at least 10 percent sexually mature females occurring within each recovery—priority management area has been achieved, and when (2) sufficient population numbers are present to maintain stability. Actions Needed 1. Restore habitats and functions of the Missouri and Mississippi River ecosystems while minimizing impacts on other uses of the rivers. 2. Protect pallid sturgeon and their habitat, and minimize threats from existing and proposed human activities. 3. Increase public awareness of the laws and needs for protecting pallid sturgeon. 4. Establish refugia of pallid sturgeon broodstock. 5. Obtain information on life history and habitat requirements of all life stages of pallid sturgeon. vii : 6. Research additional solutions to the impacts of human activities on pallid sturgeon and their habitat. 7. Obtain information on genetic makeup of hatchery—reared and wild Scaphirhynchus stocks. 8. Obtain information on population status and trends. 9. Obtain information on chemical contamination of pallid sturgeon and