1 / 28

Justin Seibert 1,2 , Kasey Yallaly 2 , Sara Tripp 2 , Dave Herzog 2 , Quinton Phelps 2

Use of harvest simulation models for Silver Carp populations in several Midwestern U.S. rivers: Implications for management of invasive populations. Justin Seibert 1,2 , Kasey Yallaly 2 , Sara Tripp 2 , Dave Herzog 2 , Quinton Phelps 2 1 Spokane Tribe of Indians

inga
Download Presentation

Justin Seibert 1,2 , Kasey Yallaly 2 , Sara Tripp 2 , Dave Herzog 2 , Quinton Phelps 2

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Use of harvest simulation models for Silver Carp populations in several Midwestern U.S. rivers: Implications for management of invasive populations Justin Seibert1,2, Kasey Yallaly2, Sara Tripp2, Dave Herzog2, Quinton Phelps2 1Spokane Tribe of Indians 2Missouri Department of Conservation

  2. Silver Carp • Jumping Carp • Nonnative invasive species • “Asian Carp” 1 of 5 • Silver and bighead are ones threatening the Great Lakes • Introduced for aquaculture in 1970’s • Filter-feeders • Floods • Expanded range in Midwestern rivers

  3. Silver Carp • Able to tolerate wide range of environmental conditions • Extremely efficient feeders • High fecundity • Rapid growth rates • Lack of natural predators • R-selected characteristics

  4. Silver Carp • Diet overlap with native planktivores (Sampson et al. 2009) • Negative impacts on native planktivores (Irons et al. 2007; Q. Phelps unpublished)

  5. Introduction • Aquatic Nuisance Species Task Force formed the Asian Carp Working Group • Develop national management and control plan for silver carp

  6. Introduction • In order to control silver carp and reduce their negative impacts: • #1 Implement commercial fishing • For commercial fishing to be successful, we need to understand: • Response of silver carp populations to harvest • Size of fish needed to target • Level of exploitation needed to reduce population

  7. Introduction • In order to evaluate these… • Developing population level models essential • But 1st a thorough understanding of demographics

  8. Introduction • Spawning potential ratio model • Demographic parameters • Traditionally used to prevent recruitment overfishing of sport fish • Determine target size and exploitation • Recruitment overfishing • Ultimately, these data will be used by agencies to guide future silver carp management.

  9. Objectives • Objective 1 • Obtain demographic information (i.e., recruitment, growth, mortality, length-weight regressions, and sex ratios) of silver carp populations from 7 Midwestern Rivers • Illinois, Missouri, Ohio, Wabash, Upper, Middle, and Lower Mississippi Rivers

  10. Objectives • Objective 2 • Using this demographic information collected from Objective 1 • Simulate spawning potential ratio models • Determine target size • Level of exploitation

  11. Collection • Collected silver carp from each river: • Illinois, Missouri, Ohio, Wabash, Upper Mississippi, Middle Mississippi, and Lower Mississippi Rivers • Fall of 2011 • Boat electrofishing • Length, weight, sex and removed lapilli otoliths

  12. Methods • Fishery Analysis and Model Simulator (FAMS) • (Slipke and Maceina 2010) • Von Bertalanffy • Mean length-at-age • Catch-curve analysis • Descending limb • Length-weight regressions

  13. Population Simulations • FAMS • Parameters in model • Growth rates, mortality rates, sex ratios • Conditional natural mortality from maximum age (Hoenig method) • Age-3 age at maturation • Fecundity-length equation (Baerwaldt and Garvey, SIUC unpublished)

  14. Population Simulations • Spawning potential ratio 0 to 1 • 0.2 (i.e., 20%) Threshold for recruitment overfishing • Various exploitation rates (i.e., 5% - 95%) • Varying target harvest lengths • (e.g., 300 mm, 400 mm, 500 mm, and 600 mm)

  15. RESULTS Length frequency distributions

  16. Age frequency graphs Mortality rates ranged 42-77%

  17. Population Simulations • Parameters for spawning potential models • Growth coefficients range = 0.176-0.27 • Maximum age range = 8-13 years

  18. Spawning potential models • 600 mm only Wabash River at 87% exploitation • 500 mm 49-76% exploitation • 400 mm 34-44% exploitation • 300 mm 27-33% exploitation • Illinois River highest • Wabash River lowest

  19. Discussion • Few studies have assessed growth in U. S. • Middle Mississippi River -Williamson and Garvey in 2004 • Mean length 650 mm at age-3 • Mean length 653 mm at age-6 (this study) • Illinois River in 2006 (Irons et al. 2011) • Length-frequency distributions • range of mean length at age 3 of 538-633 mm and at age 4 a range of 682-760 mm • Considerably higher than this study • 472 mm mean length at age-3 and 496 mm at age 4

  20. Discussion • Increased abundance of silver carp • Growth influenced by food availability (Tripathi 1989; Hagiwara and Mitsch 1994; Liang et al. 1999) • Density dependent growth (Murty et al. 1978; Opuszynski 1980; Leventer 1987)

  21. Discussion Seibert and Phelps 2013 • Mortality of wild silver carp populations • “difficult to age” Kolar et al. (2005) • Maximum age within middle Mississippi River twice as high than Williamson and Garvey in 2004 • Silver carp “settling in” • Native range • 15 years • 13 years (this study)

  22. Population Simulations • Intensively commercial exploited (i.e., 33-44%) at a small size (i.e., 300 to 400 mm) • Problems • Commercial fisherman • Large fish • Cannot harvest just large fish • Small mesh size of nets • Increased bycatch • However, something needs to be done to reduce silver carp • Greater than 50% of fish community in Illinois River

  23. Overall Conclusions • Baseline of population demographics for several Midwestern rivers • Silver carp harvest goals and target size • 300-400 mm at intermediate harvest • Can not just harvest large silver carp • Overall, this study provides information to multiple federal and state agencies that is essential to managing the invasive silver carp!

  24. Future Research • Monitor harvest of silver carp • Effect of harvest on silver carp populations • Fish community response • Possible biotic or abiotic factors structuring populations within Midwestern rivers

  25. Acknowledgements • Dr. Brent Nichols and Spokane Tribe of Indians • Dr. Taylor, Dr. Scheibe, Dr. Kraemer • MDC Field station: DO, Dawn Henderson, Frank Nelson, Susan Reinagle, and Jason Crites. • Also, Levi Solomon, Tom Stefanavage, Ron Brooks, Nick Keeton, Chris Hickey, Paul Rister, Neil Jackson, Ryan Kausing, Andrew Friedunk, and Nathan Redecker, Dr. Chipps, Dr. Willlis, Dr. Mark Fincel, Dr. Mark Kaemingk, Jason Sorensen, Chris Longhenry, Gary Knecht, Andy and Angelia Frederick. I would also like to thank Jim Garvey and Kelly Baerwaldt.

  26. Application to Lake Roosevelt • WALLEYE • Invasive species • Sport fish • Current population • Over abundant • Poor condition • Small fish • Unbalanced ecosystem • Apex predator

  27. Application to Lake Roosevelt • Eradication impossible within Lake Roosevelt • Improve fish community and satisfy anglers • SPR and Yield per recruit models • Amount of exploitation needed to reduce population • Manage for fewer larger individuals • Help balance the ecosystem • Increase health/growth of walleye • Ultimately, these models can be used to evaluate new regulation changes to determine if desired exploitation rates are reached.

  28. N = Nucleus X = Ring 8-year old silver carp

More Related