Mississippi Valley Division Engineer Research and Development Center Conservation Plan for the Interior Least Tern, Pallid Sturgeon, and Fat Pocketbook Mussel in the Lower Mississippi River (Endangered Species Act, Section 7(a)(1)) MRG&P Report No. 4 • November 2014 MRG&P Report No. 4 November 2014 Conservation Plan for the Interior Least Tern, Pallid Sturgeon, and Fat Pocketbook Mussel in the Lower Mississippi River (Endangered Species Act, Section 7(a)(1)) K. Jack Killgore, Todd Slack, Richard Fischer, Jan Hoover, and Audrey Harrison Environmental Laboratory U.S. Army Engineer Research and Development Center 3909 Halls Ferry Road Vicksburg, MS 39180-6199 Paul Hartfield U.S. Fish and Wildlife Service Ecological Services 6578 Dogwood View Parkway, Suite A Jackson, MS 39213 David Biedenharn Biedenharn Group, LLC 3303 Woodlands Place Vicksburg, MS 39180 Barb Kleiss Mississippi Valley Division U.S. Army Corps of Engineers 1400 Walnut Street Vicksburg, MS 39180 Final report Approved for public release; distribution is unlimited. MRG&P Report No. 4 ii Abstract Section 7(a)(1) of the Endangered Species Act (ESA) requires all federal agencies to use their authority as appropriate to carry out programs for the conservation (i.e., recovery) of endangered and threatened species. For more than a decade, the U.S. Army Corps of Engineers (USACE) has worked with the U.S. Fish and Wildlife Service (USFWS) and state conservation agencies to identify and resolve endangered species and ecosystem management issues that could impact USACE civil works missions in the Lower Mississippi River (LMR). It has become apparent that the very programs that have most significantly affected the river are potentially the most important and cost-effective tools to maintain and enhance its ecological functions. This is accomplished by considering and incorporating ecological engineering opportunities during the design phase of channel improvement and channel maintenance projects. The USACE has also opportunistically implemented cost-effective secondary channel restoration actions in the LMR by sharing responsibilities and resources with partner agencies. Cumulatively, both the site-specific engineering actions and the restoration opportunities have significantly benefitted the habitat baselines of endangered species associated with the LMR channel. Herein, the USACE outlines the programmatic mechanisms by which the Channel Improvement Program of the Mississippi River and Tributaries project is being utilized to implement conservation measures that maintain and improve habitat values within the LMR for recovery of endangered and other trust species inhabiting the river channel. This program has been developed under informal consultation with the USFWS, and complies with section 7(a)(1) of the ESA, USACE Environmental Operating Principles, Civil Works Ecosystem Restoration Policy (ER 1165-2-501), and supports the conservation intent of EO 13186 Responsibilities of Federal Agencies to Protect Migratory Birds. DISCLAIMER: The contents of this report are not to be used for advertising, publication, or promotional purposes. Citation of trade names does not constitute an official endorsement or approval of the use of such commercial products. All product names and trademarks cited are the property of their respective owners. The findings of this report are not to be construed as an official Department of the Army position unless so designated by other authorized documents. DESTROY THIS REPORT WHEN NO LONGER NEEDED. DO NOT RETURN IT TO THE ORIGINATOR. MRG&P Report No. 4 iii Contents Abstract .......................................................................................................................................................... ii Figures and Tables ........................................................................................................................................ vi Preface ......................................................................................................................................................... viii 1 Introduction ............................................................................................................................................ 1 Background .............................................................................................................................. 1 Purpose and Scope .................................................................................................................. 3 2 Environmental Setting ......................................................................................................................... 4 Geomorphology ........................................................................................................................ 4 Hydrology and Hydraulics......................................................................................................... 6 Habitat Classification and Distribution ................................................................................... 7 Effects of Climate Change on the Mississippi River System ................................................ 11 3 Authorized Project Description ........................................................................................................13 Channel Improvement Program ............................................................................................. 13 River Engineering Structures ................................................................................................. 13 Revetments ................................................................................................................................ 14 Dikes ........................................................................................................................................... 15 Bendway Weirs ........................................................................................................................... 20 Hardpoints .................................................................................................................................. 20 Roundpoints ............................................................................................................................... 21 Chevrons ..................................................................................................................................... 21 Dredging ................................................................................................................................. 21 4 Endangered Species Accounts ........................................................................................................ 24 Interior Least Tern .................................................................................................................. 24 Life History .................................................................................................................................. 24 Distribution ................................................................................................................................. 26 Breeding and Nesting Habitat ................................................................................................... 28 Wintering .................................................................................................................................... 29 Abundance ................................................................................................................................. 29 LMR Recovery Status ................................................................................................................. 32 Pallid Sturgeon ....................................................................................................................... 33 Habitat ........................................................................................................................................ 34 Movement ................................................................................................................................... 35 Feeding ....................................................................................................................................... 36 Spawning .................................................................................................................................... 36 Early Life History ........................................................................................................................ 37 Distribution and Abundance ...................................................................................................... 38 LMR Recovery Status ................................................................................................................. 45 MRG&P Report No. 4 iv Fat Pocketbook Mussel .......................................................................................................... 46 Habitat ........................................................................................................................................ 46 Movement ................................................................................................................................... 47 Feeding ....................................................................................................................................... 47 Reproduction .............................................................................................................................. 47 Distribution