The Migratory and Reproductive Response of Spawning Lake Sturgeon to Controlled Flows over Kakabeka Falls on the Kaministiquia River, ON 2006 Lake Superior QUIK Report 06.02 M.J. Friday TABLE OF CONTENTS List of Tables ……………………………………………………………………………. ii List of Figures …………………………………………………………………………… ii Introduction ……………………………………………………………………………... 1 Study Area ………………………………………………………………………………. 1 Materials and Methods ………………………………………………………………….. 3 Radio Tagging ………………………………………………………………….... 3 Tracking …………………………………………………………………………. 3 Drift Netting ……………………………………………………………………... 5 Water Temperature, Velocity and Depth ………………...………………………. 5 Results …………………………………………………………………………………… 6 Radio Tagging……………………………………………………………………. 6 Migration ……………………………………………………………………….... 6 Spawning Events ………………………………………………………………… 9 Drift Netting ……………………………………………………………………... 9 Summary ………………………………………………………………………………… 12 Acknowledgements ……………………………………………………………………… 12 References ……………………………………………………………………………….. 12 Glossary ………………………………………………………………………………….. 13 LIST OF TABLES Table Pg. 1 Fish attribute information for 14 adult sturgeon radio tagged in 2006, four tagged in 2005 and six tagged in 2000 4 2 The history of spawning migrations to Kakabeka Falls among six lake sturgeon internally radio tagged in the fall of 2000 7 3 Migration dates and spill flows 2006 9 4 The drift netting incidental catches 10 LIST OF FIGURES Figure Pg. 1 The Kaministiquia River watershed and major reservoirs 2 2 The study area from Kakabeka Falls downstream to the OPG generating station 3 3 The Kaministiquia River from Kakabeka Falls downstream to Lake Superior 9 4 Water temperature and spill flow over Kakabeka Falls from May 1 to July 20, 2005 6 5 The migratory behaviour of spawning group 1 and 2 in relation to spill flows and water temperature 7 6 Spill flows at Kakabeka Falls in relation to tagging dates, approximate spawning dates, and catches of downstream drifting larvae 8 7 Water temperature at Kakabeka Falls in relation to tagging dates, approximate spawning dates, and catches of downstream drifting larvae 10 8 Mean total length distribution of lake sturgeon larvae collected below Kakabeka Falls during the first and second drift events in 2005 11 9 The daily minimum, maximum and average total length range of larval lake sturgeon collected below Kakabeka Falls in 2005 11 ii INTRODUCTION In 2002, the Ontario Ministry of Natural Resources (OMNR) and Ontario Power Generation (OPG) commenced water management planning for the Kaministiquia River watershed. The Water Management Plan that was developed included an agreement to study lake sturgeon in the Kaministiquia River (OPG 2005). One component of the agreement was to examine lake sturgeon spawning activity during different flow conditions over Kakabeka Falls. Access of adult sturgeon to the spawning site at the base of Kakabeka Falls may be impeded or delayed due to low flow conditions resulting from the operation of the generating station (GS) located downstream of the falls. Studies conducted in 2004 and 2005 indicate that adult sturgeon reached the spawning site and spawned successfully during 23 m3∙s-1 flow over Kakabeka Falls. In 2006 we examined a lower flow condition (17 m3∙s-1) to determine if migration and successful spawning would occur. As was the case in 2004 and 2005, OPG attempted to control flow from May 15 to June 30. Within this timeframe a minimum flow of 17 3m ∙s-1 would spill over the falls until June 25. Starting on June 26 flow over the falls would be reduced by 3 m3∙s-1 and continue every 24 h until scenic flows were attained (June 30). This report details the third year of research examining lake sturgeon spawning migrations and reproductive success during controlled flows over Kakabeka Falls. The objectives of the studies were to: 1. Determine if spawning lake sturgeon can successfully migrate upstream from the generating station to the base of the Falls during spill flows of 17 3m ∙s-1; 2. Determine if spawning lake sturgeon can successfully migrate out of the study area during flow conditions of 17 m3∙s-1; 3. Determine the length of time spawning adults remain in the study area; 4. Determine the approximate date when spawning occurs; 5. Determine if the spawning process was successful at spill flow rates of 17 3m ∙s-1; 6. Confirm, through the collection of larval sturgeon, that there are sexually mature adult sturgeon spawning in the study area; 7. Confirm that previously documented upstream migrations into the study area are primarily spawning migrations and not exploratory movements; and 8. Determine the timing and duration of downstream movement of larval lake sturgeon STUDY AREA These studies focused on an 800 m stretch of the Kaministiquia River (Figures 1, 2 and 5) from the base of Kakabeka Falls where lake sturgeon spawning has been documented, downstream to the generating station (GS). The general habitat characteristics of this area are described in Friday (2004). 1 K ashabo w ie La ke M a ta w in D o g La ke R iver S hebando w an G re en w ate r La ke Lake L ake S tud y A re a S upe rior K am in istiquia R iver K ilo m e tr es L a k e S u p e r io r Figure 1. The Kaministiquia River watershed and major reservoirs. 2 K a kabe ka F a lls P lun ge P oo l W est C h anne l E a st C ha nne l R ap id s P oo l D rift N e ttin g S ite R efe ren ce T ran sm itte r D a ta po ol Lo gge r K a kabe ka F a lls G e ne ra tin g S ta tion R ap id s Figure 2. The study area from Kakabeka Falls downstream to the OPG generating station. MATERIALS AND METHODS Radio Tagging Radio telemetry equipment manufactured by Advanced Telemetry Systems (ATS) was used in this study1 . Each radio transmitter (n = 14) was identified by a unique frequency between 150.934 – 151.214 MHz. The 20 g transmitters (model F2060) pulsed 55 times per minute and had a battery life of approximately 10 months. To catch sturgeon for tag attachment 45 m of 304 mm (12”) stretched mesh, multifilament gill net was set overnight at river kilometer (rkm)19 (Figure3). Netting was carried out from April 25 to May 4 during water temperatures that averaged 8.2°C. Of twenty one sturgeon captured, 14 individuals that had not been previously radio tagged during any other study were fitted with external transmitters (Table 1) following the procedures outlined in Friday (2004). All sturgeon were sampled for length (fork, total and legal), weight, girth, body depth and were tagged with a five digit orange floy tag applied along the left hand side of the dorsal fin. We attempted to determine fish gender by forcing eggs or milt from the genital opening. Tracking A shoreline based data logger (model R4500) was installed upstream of the generating station (Figure 2) in mid April to track the movements of radio tagged sturgeon as they migrated into and out of the study area. A two antennae system was used to Figure 3. The Kaministiquia River from Kakabeka Falls downstream to Lake Superior 3 1Reference to trademark names does not imply endorsement by the Ontario government Table 1. Fish attribute information (from the original tagging date) for 14 adult sturgeon radio tagged in 2006, four tagged in 2005 and six tagged in 2000 (frequencies in bold italics denote fish that did not migrate into the study area during the 2006 spawning period; frequencies with an * denote fish that migrated during 17 m3∙s-1 spill). Gill to dorsal Fork Total fin Length Length Girth Weight Body Length Tagging Location (mm) (mm) (mm) (kg) Depth (mm) Sex Freq Tagging Date (km number) 1505 1625 645 23.5 210 1020 F? * 953 25-Apr-06 Km 19 1180 1285 440 9.5 160 760 ? * 993 26-Apr-06 Km 19 1295 1425 585 19 195 845 ? * 973 26-Apr-06 Km 19 1340 1450 555 17.5 175 850 ? 1053 26-Apr-06 Km 19 1330 1450 555 17.5 185 835 ? 1113 26-Apr-06 Km 19 1285 1440 600 18.5 190 830 ? 1173 26-Apr-06 Km 19 1410 1540 590 20.5 190 920 ? 1032 27-Apr-06 Km 19 1375 1500 595 19 210 850 ? 1134 27-Apr-06 Km 19 1250 1380 785 13.5 160 785 ? 1093 27-Apr-06 Km 19 1325 1470 595 20 195 860 ? * 1193 02-May-06 Km 19 1530 1675 680 27 225 1065 F? 1012 02-May-06 Km 19 1300 1420 545 15.5 185 855 ? 1073 02-May-06 Km 19 1295 1420 560 17.6 180 820 ? 1214 02-May-06 Km 19 1230 1360 535 15.5 170 785 ? * 934 04-May-06 Km 19 1015 1130 470 10.2 155 610 ? 777 29-Apr-05 Km 19 1090 1215 450 10.7 165 700 ? 884 27-Apr-05 Km 19 1270 1390 515 15.9 160 840 ? * 812 03-May-05 Km 19 1240 1355 520 14.8 180 765 ? * 826 28-Apr-05 Km 19 1324 1417 19.3 867 ? * 74 14-Sep-00 Km 19 1420 1494 24.7 915 ? * 132 15-Sep-00 Km 11 1239 1345 13.4 781 ? * 254 06-Sep-00 Km 14 1230 1285 15.6 776 ? 214 02-Oct-00 Km 14 1355 1490 19.9 875 ? * 293 02-Oct-00 Km 14 1240 1343 16.9 787 ? * 311 02-Oct-00 Km 14 interpret the direction of fish movement as one antenna was facing upstream (toward the falls) and the other was facing downstream (toward the GS). A reference transmitter (150.894 MHz) was placed in the river above the GS (Figure 2) to provide a known signal strength from a fixed position. Radio tagged fish were determined to be in the study area when the signal strength of their transmitter matched, or was close to, the reference tag signal strength.