Wade D. Smith - PowerPoint PPT Presentation

slide1 l.
Skip this Video
Loading SlideShow in 5 Seconds..
Wade D. Smith PowerPoint Presentation
Wade D. Smith

play fullscreen
1 / 19
Download Presentation
Download Presentation

Wade D. Smith

Presentation Transcript

  1. Salmon Sharks & Local Strandings Photo: Delvin Wade D. Smith

  2. Sharks are a diverse group of fishes

  3. Biological Traits Slow growth Long life spans Few offspring Accustom to few natural predators Combined, these traits = low potential for population growth & resilience

  4. Spiny dogfish Squalus acanthias May live to 100 years Doesn’t reproduce until reaching 20 or more years of age

  5. Salmon Sharks – Lamna ditropis Predominant predatory fish in the North Pacific Along our coast, salmon sharks are found from Alaska to Baja California

  6. White Sharks & Salmon Sharks White Shark Salmon Shark

  7. Salmon Sharks – Lamna ditropis Average size: 6-8 feet, maximum 12 ft. Mature at 8-10 years (females) 5 years (males) Females give birth to 2-5 pups each year May live to at least 30 years

  8. Warm-bodied Sharks Able to maintain body temperature as high as 13°C above water temperature

  9. Warm-bodied Sharks Wide range of prey: salmon, herring sablefish, dogfish, squid

  10. Tagging & Tracking Salmon Sharks Ongoing research by Alaska Dept. of Fish & Game, Stanford University (Hopkins Marine Station), and Tagging of Pacific Pelagics program

  11. Tagging & Tracking Salmon Sharks Prince William Sound

  12. Tagging & Tracking Salmon Sharks

  13. Tagging & Tracking Salmon Sharks Weng et al. (2008) Each point = daily position Wide range of habitats used

  14. Tagging & Tracking Salmon Sharks Seasonal tracks of 34 sharks Weng et al. (2008)

  15. Salmon Shark Movements Adult male & female sharks tend to segregate

  16. Salmon Shark Nursery Grounds Salmon sharks born in late spring – early summer off BC, WA, OR & CA coasts

  17. Salmon Shark “Strandings” Dead or dying young salmon sharks often wash up on beaches along their nursery grounds

  18. Thanks to: Aaron Carlisle & Ken Goldman TOPP: http://www.topp.org/species/salmon_shark

  19. Photo: Delvin