19 6 Abstract—The shortnose sturgeon (Acipenser brevirostrum) is an en- First verified occurrence of the shortnose dangered species of fish that inhab- sturgeon (Acipenser brevirostrum) its the continental slope of the At- lantic Ocean from New Brunswick, in the James River, Virginia Canada, to Florida. This species has not been documented previously in the freshwater portion of any river Matthew Balazik of the Chesapeake Bay, except in the Potomac River. On 13 March 2016, a Email address for author: [email protected] shortnose sturgeon was captured in the freshwater portion of the James Center for Environmental Studies River at river kilometer 48. The Virginia Commonwealth University fish had a fork length of about 75 1000 West Cary Street cm and was likely mature. Genetic Richmond, Virginia 23284 analysis confirmed the fish was a shortnose sturgeon and was assigned to the Chesapeake Bay–Delaware population segment. Regardless of whether this shortnose sturgeon was part of a remnant Chesapeake The shortnose sturgeon (Acipenser ture of shortnose sturgeon, as well Bay population or whether its cap- brevirostrum) is an amphidromous (Spells1; Welsh et al., 2002; Mangold ture there is an indicator of an ex- sturgeon reported to inhabit the con- et al.2). Only one genetically verified pansion of range from the Delaware tinental slope of the Atlantic Ocean shortnose sturgeon was collected in River by way of the Chesapeake and from New Brunswick, Canada, to Virginia waters as part of these pro- Delaware Canal, dedicated research Florida (Gruchy and Parker, 1980; grams (Spells1; Welsh et al., 2002). is needed to determine the status of Dadswell et al., 1984; Kynard, 1997). One other fish captured was hypoth- the shortnose sturgeon inhabiting However, Dadswell et al. (2013) docu- esized to be a shortnose sturgeon the Chesapeake Bay. mented a single shortnose sturgeon but could not be verified at the spe- captured in a weir in the Minas Ba- cies level because no genetic sample sin, an inlet of the Bay of Fundy in was taken (Spells3). Both the veri- Nova Scotia, Canada, and that cap- fied and suspected shortnose stur- ture represents a modest extension geon were collected at the mouth of of the northern range for this species. the Rappahannock River, a marine In the United States, the shortnose portion of the Chesapeake Bay estu- sturgeon was listed as endangered in ary. In the Maryland reward pro- 1967, under the Endangered Species Preservation Act, and is currently 1 Spells, A. J. 1998. Atlantic sturgeon protected under the U.S. Endangered population evaluation utilizing a fishery Species Act. In 2012, the shortnose dependent reward program in Virgin- sturgeon was listed as a species of ia’s major western shore tributaries to concern under the Canadian Species the Chesapeake Bay, 5 p. An Atlantic Coastal Fisheries Cooperative Manage- At Risk Act. ment Act Report for National Marine The Chesapeake Bay is located Fisheries Service. U.S. Fish Wildl. Serv., roughly in the middle of the report- Charles City, VA. [Available from Har- ed geographic range of the shortnose rison Lake National Fish Hatchery, U.S. Fish Wildl. Serv., 11110 Kimages Rd., sturgeon (Fig. 1), but because of the Charles City, VA 23030-2844.] Manuscript submitted 11 September 2016. scarcity of this species, research 2 Mangold M., S. Eyler, S. Minkkinen, and Manuscript accepted 19 January 2017. dedicated to shortnose sturgeon in B. Richardson. 2007. Atlantic stur- Fish. Bull. 115:196–200 (2017). the Chesapeake Bay has been ex- geon reward program for Maryland wa- Online publication date: 2 February 2017. tremely limited. During 1996–2006, ters of the Chesapeake Bay and tributar- doi: 10.7755/FB.115.2.6 ies 1996–2006, 22 p. [Summary report] research programs that focused on Maryland Fish. Resour. Off., U.S. Fish Atlantic sturgeon (A. oxyrinchus) Wildl. Serv., Annapolis, MD. [Available The views and opinions expressed or throughout the Chesapeake Bay es- from website.] implied in this article are those of the 3 tuary and that provided a monetary Spells, A. 2014. Personal commun. author (or authors) and do not necessarily Harrison Lake National Fish Hatchery, reflect the position of the National reward for reporting captured stur- U.S. Fish Wildl. Serv., 11110 Kimages Marine Fisheries Service, NOAA. geon provided evidence of the cap- Rd., Charles City, VA 23030-2844. Balazik: First occurrence of Acipenser brevirostrum in the James River, Virginia 197 nose sturgeon captured during the 1 cm = 15 km Chesapeake and programs. Delaware Canal Only 2 studies (Welsh et al., 2002; Kynard et al., 2009) were fo- cused specifically on the life his- tory of shortnose sturgeon in the Chesapeake Bay. Welsh et al. (2002) telemetered 13 shortnose sturgeon, Delaware which were initially captured and Bay tagged in the marine part of the es- tuary. Of these 13 fish, 3 shortnose sturgeon were later detected in the Chesapeake and Delaware Canal or in the Delaware River (Welsh et al., 2002). Kynard et al. (2009) focused Potomac River their research on the life history of shortnose sturgeon in the Potomac River. After extensive sampling and Rappahannock River work with commercial fishermen, they captured 2 shortnose sturgeon. Both fish were gravid females, and Chesapeake telemetric and recapture data indi- Bay cated that one fish spawned in the Potomac River (Kynard et al., 2009). As with the genetic samples collected during the Chesapeake Bay reward James River program, the 2 gravid females could not be genetically differentiated from Atlantic Delaware River shortnose sturgeon Ocean (King et al., 2014). As of this writ- ing, the only documented occurrence of a shortnose sturgeon has been the sole occurrence of this species in the freshwater portion of a river in the Chesapeake Bay (Welsh et al., 2002; Kynard et al., 2009). Figure 1 Map of the Chesapeake Bay showing, to our knowledge, all known fresh- Materials and methods water locations where shortnose sturgeon (Acipenser brevirostrum) were captured in the Chesapeake Bay. The black dot marks the location where the shortnose sturgeon was captured on the James River in this study. On 13 March 2016, a gill net was set The 2 triangles are the capture locations on the Potomac River for the at river kilometer 48 of the James 2 gravid female shortnose sturgeon documented by Kynard et al. (2009). River (Fig. 1), Virginia, in an at- tempt to collect juvenile Atlantic sturgeon (under NOAA Endangered gram, 72 shortnose sturgeon were documented during Species Permit no. 16547, VCU IACUC#AD20127). The 1996–2006; however, because of problems with obtain- gill net that captured the shortnose sturgeon was 8.3- ing collection permits, Maryland scientists were not cm stretch mesh and had a stretched height of 1.8 m. allowed to tag 26 shortnose sturgeon collected after The net was set parallel to the water current and de- May of 2002 (Mangold et al.2). There is a chance that ployed at a depth of 3.2 m. Water quality data at the some of the 26 shortnose sturgeon were unknowing- capture location was determined by using a calibrated ly recaptured during the reward program. Results of YSI Model 854 hydrometer (YSI Inc., Yellow Springs, analysis of the genetic samples taken from shortnose OH). At the sampling location, the temperature was sturgeon as part of the reward program indicated no 12°C, dissolved oxygen was 9.89 mg/L, and salinity was distinct difference between fish from the Chesapeake 0.04. The net was set for 2 h and pulled during ebb cur- Bay and from the Delaware River and Bay; there- rent just before slack water. fore, the 2 groups were assigned to the same popu- lation segment (Grunwald et al., 2002; Wirgin et al., 4 Mention of trade names or commercial companies is for iden- 2010; King et al., 2014). Researchers did not mention tification purposes only and does not imply endorsement by milt production or egg release for any of the short- the National Marine Fisheries Service, NOAA. 19 8 Fishery Bulletin 115(2) A B Figure 2 Photographs showing the differences in mouths and noses between the Atlantic sturgeon (Acipens- er oxyrinchus) and the shortnose sturgeon (A. brevirostrum). (A) Photograph of the shortnose stur- geon, with an estimated 75-cm fork length, described in this article (photo credit M. Balazik, Virginia Commonwealth University). (B) Photograph showing the differences in the mouths and noses of an Atlantic sturgeon (65-cm fork length, left) and a shortnose sturgeon (76 cm fork length, right) (photo credit W. Post, South Carolina Department of Natural Resources). Results Shortnose sturgeon mature sexually at approxi- mately 50 cm FL (Dadswell et al., 1984; Bain, 1997); A sturgeon estimated to be about 75 cm long (in fork therefore, the fish caught in the James River was likely length [FL]) was caught during the net set (Fig. 1). to have been a mature fish. It was roughly the same This estimated FL reflects the opinion of the experi- size as the 2 gravid females caught in the Potomac enced researchers and their analysis of photographs River during the Kynard et al. (2009) study. The late- that have objects in the background to judge the size stage shortnose sturgeon caught at river kilometer 63 of fish. The sturgeon was initially thought to be a sub- of the Potomac River was 75 cm FL and was captured adult Atlantic sturgeon, and standard protocols were on 22 March 2006 (Kynard et al., 2009). The late-stage followed to process this fish (Kahn and Mohead, 2010). shortnose sturgeon caught at river kilometer 63 of the A fin was clipped and taken for genetic purposes, and Potomac River was 75 cm FL and was captured on 22 a passive integrated transponder was placed under March 2006 (Kynard et al., 2009)—at a location and the dorsal fin.