1 / 32

Fisheries Science and the Striped Bass

Fisheries Science and the Striped Bass. A Classroom Lesson from the Mathematics & Science Center. Striped Bass: A Success Story!. Why? Because of …. Fisheries Science … and then… proper fish management!. Fisheries Science Involves:. Biology/Life Cycle Genetics Ecology

carlyn
Télécharger la présentation

Fisheries Science and the Striped Bass

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. Fisheries Science and the Striped Bass

  2. A Classroom Lesson from theMathematics & Science Center

  3. Striped Bass: A Success Story!

  4. Why? Because of …. Fisheries Science … and then… proper fish management!

  5. Fisheries Science Involves: • Biology/Life Cycle • Genetics • Ecology • Population Studies • Taxonomy • Fisheries Technology • Management ( & politics!)

  6. In the Chesapeake Bay… • Salinity = 0.5 to 32 ppt • 50% depth < 20 ft. • Temp range = 1 – 30° C • Largest U.S. Estuary • Oxygen levels vary • (O to saturated)

  7. …Fish Fauna Flourish! Not many “residents” – most are visitors! 267 species in the bay Only 32 species are year-round!

  8. Fish & their Waters… • Freshwater (0 – 5 ppt) • Estuarine (0.5 to 32 ppt) • Marine (> 30 ppt) • Anadromous Species of fish– Lives in Salt water, spawns in Fresh

  9. The Scientific Question: How many fish do we have… ...and how many can we catch… …without harming the fish stock?

  10. A Stock Assessment A special type of study of the carrying capacity of an area for a fish population that is “harvested” or managed • Fish Biology • Fishing Practices • Catch Per Unit Effort (CPUE)

  11. Methods of Fish Science

  12. Otoliths – How Old is a Fish?

  13. Otolith Rings = Fish Age

  14. Graphs of Fish Populations

  15. Fish Length Graph Fish Length (avg.) Year

  16. Length = Age Female Striped Bass… …is able to reproduce… … at 4 years old!

  17. Tagging – Where they go!

  18. Inserting the tag

  19. A Tagged Fish

  20. Dissections – What they eat

  21. A Favorite treat!

  22. Prey of the Striped Bass

  23. DNA – Fish Genetics

  24. Whose Eggs?

  25. DNA Patterns of Chesapeake Bay Sportfish 2,036 1,636 1,018 517/506 396 344 298 220/201 154/134 Bluefish Summer flounder Southern kingfish } Spanish mackerel } Spotted sea trout } Northern kingfish } Atlantic croaker } Cobia } Black sea bass Black drum Silver perch Striped bass Red drum Weakfish Tautog Spot

  26. DNA Says --- • Bass Mitochondrial DNA • RFLP, Gel Electrophoresis • Pattern for each species

  27. Fishing Practices • Who is doing the fishing… • Catch Per Unit Effort (CPUE)

  28. By-catch – A Critical Issue

  29. Keep or Release?

  30. Some Major Things We’ve Learned… • Reduced populations from overfishing INCREASES the effects of natural stresses • Acid rain and other chemicals (copper, aluminum) are toxic • Fluctuation of water temp. in spawning grounds is most significant natural stress

  31. Maximum Sustainable Yield • The number of fish we can catch per year and not hurt the stock • Usually occurs at ½ of the carrying capacity • Not too many fish for competition, but enough for a good spawning stock

  32. The Scientific End Result We learn: What age fish to catch… How many we can catch and when… and still not hurt the fish stock!

More Related