Movements of Atlantic Sturgeon of the Gulf of Maine Inside and Outside of the Geographically Defined Distinct Population Segment

Abstract

Identification of potential critical habitat, seasonal distributions, and movements within and between river systems is important for protecting the Gulf of Maine (GOM) distinct population segment of Atlantic Sturgeon Acipenser oxyrinchus oxyrinchus. To accomplish these objectives, we captured Atlantic Sturgeon from four GOM rivers (Penobscot, Kennebec system, Saco, and Merrimack) and tagged 144 individuals (83.3–217.4 cm TL) internally with uniquely coded acoustic transmitters. Tagged fish were detected from 2006 to 2014 by primary receiver arrays that were deployed in the four GOM rivers or were detected opportunistically on a secondary group of receivers deployed within the GOM and along the continental shelf. Tagged Atlantic Sturgeon were documented at three spawning areas in the Kennebec system in June and July, including an area that became accessible in 1999 when Edwards Dam was removed. The majority (74%) of tagged fish were detected in the estuaries of the four GOM rivers, primarily in May–October. They spent most of their time in a 45-km reach within the Kennebec system but occupied more limited areas (≤5-km reach) within the Penobscot, Saco, and Merrimack rivers. Approximately 70% of the tagged fish were detected in GOM coastal waters and aggregated in the Bay of Fundy (May–January), offshore of the Penobscot River (September–February and May), offshore of the Kennebec River (September–February), in Saco Bay and the Scarborough River (July–November), and along the eastern Massachusetts coast between Cape Ann and Cape Cod (April–February). Nine tagged Atlantic Sturgeon (7%) left the GOM; three of those individuals moved north as far as Halifax, Nova Scotia, Canada, and six moved south as far as the James River, Virginia. Information obtained in this study has been used to make recommendations to avoid or reduce the impacts of in-water projects on Atlantic Sturgeon.

Received July 15, 2016; accepted November 27, 2016

ACKNOWLEDGMENTS

This research was funded by NMFS grants NA06NMF-4720249A, NA07NMF4720053, and NA10NMF4720023. All methods were conducted under National Oceanic and Atmospheric Administration (NOAA) ESA Section 10 Permit numbers 1549, 1578, 1595, 16306, and 16526 for the take of protected species for scientific purposes. Research in the Penobscot River was conducted under the University of Maine Institutional Animal Care and Use Committee protocol numbers A2008-07-01, A2011-06-11, and A2014-05-06. We thank Matthew Altenritter, Jason Bartlett, Greg Beadle, James Beaudry, Toby Bonney, Amy Carlson, Edith Carson, Phillip Dionne, Claire Enterline, Steve Fernandes, Nathaniel Gray, Catherine Johnston, Cheryl Kieffer, Craig King, Kevin Lachapelle, Josh Noll, Mark Pasterczyk, Ian Trefrey, Matthew Wegener, and George Zink for their assistance in capturing and tagging Atlantic Sturgeon and maintaining the receiver arrays. The views expressed herein are those of the authors and do not necessarily reflect the views of the Penobscot River Restoration Trust, the NOAA, or any of their members or subagencies; or the Maine Agricultural and Forest Experiment Station. We also thank the following GOM Coastal Tracking Network, ACT Network, and OTN researchers, staff, and partner organizations that maintained receivers outside the four study rivers and provided data: Jay Barthelotte, Rod Bradford, Robert Branton, Jeremy Broome, Nicholas Buchan, Christian Conroy, Michael Dadswell, Greg DeCelles, Keith Dunton, Michael Frisk, Graham Goulette, Jonathan Grabowski, James Hawkes, David Hebert, William Hoffman, Adrian Jordaan, Richard Karsten, Christina Kennedy, Jeff Kneebone, John Kocik, Matthew Litvak, Martha Mather, Kim McKown, Paul Music, Ron O’Dor, Anna Redden, Tom Savoy, Jinyu Sheng, Greg Skomal, Peter C. Smith, Michael Stokesbury, Brian Tarbox, Winsor Watson, Carter Watterson, Fred Whorisky, Acadia University, Connecticut Department of Energy and Environmental Protection, Dalhousie University, Department of Fisheries and Oceans Canada, Massachusetts Division of Marine Fisheries, Mount Allison University, NMFS, New York Department of Environmental Conservation, Northeastern University, Southern Maine Community College, Stony Brook University, U.S. Department of the Navy, University of Massachusetts–Amherst, University of Massachusetts–Dartmouth, and University of New Hampshire–Durham.