Comparing abundance estimates from closed population mark-recapture models of endangered adult Atlantic sturgeon

Abstract

ESR Endangered Species Research Contact the journal Facebook Twitter RSS Mailing List Subscribe to our mailing list via Mailchimp HomeLatest VolumeAbout the JournalEditorsSpecials ESR 39:63-76 (2019) - DOI: https://doi.org/10.3354/esr00957 Comparing abundance estimates from closed population mark-recapture models of endangered adult Atlantic sturgeon J. E. Kahn1,2,*, C. Hager3, J. C. Watterson4, N. Mathies3, K. J. Hartman2 1National Marine Fisheries Service, Office of Protected Resources, Silver Spring, Maryland 20910, USA 2Division of Forestry and Natural Resources, West Virginia University, Morgantown, West Virginia 26506-6125, USA 3Chesapeake Scientific, Williamsburg, Virginia 23185, USA 4U.S. Department of the Navy, Naval Facilities Engineering Command, Atlantic Norfolk, Virginia 23508, USA *Corresponding author: jason.kahn@noaa.gov ABSTRACT: Atlantic sturgeon Acipenser oxyrinchus oxyrinchus were listed as 5 distinct population segments under the US Endangered Species Act in 2012. At that time, only 2 abundance estimates of the Atlantic sturgeon population were available: one from commercial fisheries landings in the Hudson River ending in 1995 and one from mark-recapture research in the Altamaha River, Georgia, in 2004 and 2005. In 2013, we verified spawning in the York River, Virginia, system and initiated a multiple-year mark-recapture study focusing on spawning-run abundance. We used a Schumacher-Eschmeyer model and Program CAPTURE to produce estimates of annual spawning abundances from 2013 to 2018. The Schumacher-Eschmeyer estimates of spawning-run abundance with 95% confidence intervals from 2013 to 2018 were 75 (31-190), 157 (115-244), 184 (150-238), 222 (137-576), 212 (157-328), and 145 (89-381), respectively. Because Atlantic sturgeon do not spawn every year, the trends in estimates do not suggest a recovering or declining population, but rather variability in proportions of the adult population that return to spawn each year. The estimates produced in Program CAPTURE using M0 (null), Mt (Chao Mt and Darroch), Mh (Chao Mh and Jackknife), and Mth (Chao Mth) models all produced similarly reliable estimates. The models that consider a behavioral response to initial capture (Mb, Mbh, and Mtb) failed to produce reliable estimates for this data, likely because as an endangered species, the dataset for Atlantic sturgeon was sparse. The Jackknife equation (model Mh) was the most precise every year with reliable accuracy and therefore is recommended. KEY WORDS: Anadromous · Conservation · Endangered species · Fish · Mark-recapture · Monitoring · Native fish · Population ecology · Population modeling Full text in pdf format Supplementary material PreviousNextCite this article as: Kahn JE, Hager C, Watterson JC, Mathies N, Hartman KJ (2019) Comparing abundance estimates from closed population mark-recapture models of endangered adult Atlantic sturgeon. Endang Species Res 39:63-76. https://doi.org/10.3354/esr00957 Export citation RSS - Facebook - Tweet - linkedIn Cited by Published in ESR Vol. 39. Online publication date: June 06, 2019 Print ISSN: 1863-5407; Online ISSN: 1613-4796 Copyright © 2019 Inter-Research.