DISTRIBUTION OF LAKE STURGEON FOLLOWING 11 YEARS OF STOCKING M. A. CHALUPNICKI, D. E. DITTMAN USGS Great Lakes Science Center, Tunison Laboratory of Aquatic Science, Cortland, NY 13045. D. M. CARLSON New York Department of Environmental Conservation Watertown, NY 13601 INTRODUCTION: Lake Sturgeon (Acipenser fulvescens) are native to New York and once provided a large commercial fishery. The fishery targeted spawning congregations and led to a drastic decline. Due to their slow maturity (males 12-15yrs, females 17-24yrs), long life span (80-100yrs), and irregular spawning cycle (females every 1-3yrs) populations could not recover. The fishery for lake sturgeon was closed in 1976 and classified as a threatened species in New York in 1983. A report containing the distribution and abundance of lake sturgeon from the late 1800’s to 1995 has been summarized by Carlson (1995)(Figure 1). In an attempt to help the NY Department of Environmental Conservation plan lake sturgeon restoration, a stocking program (Figure 2) was initiated to increase the number of waters containing sturgeon from 5 to 8 (Carlson et al. 2002). This study is intended to provide a summary of information on the distribution and occurrence of lake sturgeon following the 11 years of stocking in New York waters from 1993-2006 (Figure 3). Propagation was temporarily halted after 2006 at Oneida Hatchery and is expected to resume in 2009. RESULTS: Following the assessment by Carlson (1995), the distribution of lake sturgeon has increased as a direct result of the stocking initiatives (Figure 3). Lake sturgeon are now found in the eight waters, resultant of stocking in the Great Lakes watershed (Figures 4 & 5). Most sturgeon occurrences are the result of research mainly with angler records increasing as size of the initial stockings become susceptible to fishing gear (Figure 4). The natural populations found in the Grasse River, Oswegatchie River, Niagara River, Lake Ontario, Lake Erie, and St. Lawrence River still have fish being recorded, although numbers are low (Figure 6). Objectives 05-08 1) Compile current Lake Sturgeon database into a useable format 2) Assess sturgeon distribution following stocking initiatives 3) Predict suitable sturgeon habitat using GAP Analysis METHODS: A database containing records of Lake Sturgeon occurring in New York since the mid-1800’s has been compiled and maintained by the New York Department of Environmental Conservation. This database was acquired and formatted according to criteria that would be used to graphically represent their distribution across the state. These criteria included; water body, year, site description, geographic location, catch, type of observation (research, angling, dead wash-up), and any other information that came along with the record. Records that contained a site description but no geographic location were given a location by manually identifying the site using Mapsource 6.11.6 mapping software based on the general site description. Following the formatting of the records by the criteria listed, a unique identification code was assigned to each record that would allow the information associated with the record to be linked to the final map product. Once all of the records were given a unique identification code, the records were mapped across the state using ArcMap 9.2 GIS software. The stocking sites from 1993 to 2006 were also formatted and included in the analyses in order to determine affects following the addition of new individuals into the population. Once formatting was complete, records were split based on the year occurring before or after 1993, and type of observation. Records prior to 1993 were described as natural individuals with no influence from stocking and used as a baseline for comparison. Records1 following 1993 to present are described as a mix of natural individuals and introduced by stocking based on location relative to stocking sites. Figure 4: Lake Sturgeon Occurrences After Stocking Figure 1: Pre-Stocking Surgeon Distribution Genesee River 7/2008 Dawn Dittman USGS Oswego River 9/2007 Dawn Dittman USGS Figure 5: Post Stocking Sturgeon Figure 6: Naturally Reproducing Sturgeon Waters Oneida Lake 10/2008 Lake Sturgeon Recovery Committee Cayuga Lake 8/2006 Marc Chalupnicki USGS Figure 2: Lake sturgeon egg take below the Moses Saunders Dam Onondaga Lake 5/2006 Tony Siniscal SUNY ESF Lake Erie 1980’s NYDEC Lake Erie Unit Oswegatchie River 8/1998 Scott Schlueter, SUNY ESF Niagara River 5/2000, Tom Hughes & Chris Lowie USFWS 1/2005, Paul Bowser, Cornell University St. Lawrence River 6/2004 NYDEC Lake Sturgeon Egg Take St. Regis River 7/2005 Marc Chalupnicki USGS Indian River/Black Lake 5/2008 Marc Chalupnicki USGS Raquette River7/2008 Dan Prahl, USGS FUTURE GOALS: 1) Use GAP Analysis to predict suitable sturgeon habitat for New York lakes and rivers. 2) Collect additional habitat data to help predict suitable spawning sites. Grasse River 7/2007 Normandeau Assoc. Black River 5/2005 Dick Adams NYDEC Dexter Seneca River 10/2008 Marc Chalupnicki USGS References: Carlson, D. M. 1995. Lake Sturgeon Waters and Fisheries in New York State. J. Great. Lakes Res. 21(1):35-41. Carlson, D. M., R. Colesante, J. S. Hayes, and S. L. Schlueter. Lake Sturgeon (Acipenser fulvescens) and its Recovery Programs in New York State. Technical Compendium to the Proceedings of the 4th International Symposium on Sturgeon. December 2002 Figure 3: Lake Sturgeon Stocking Sites