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PowerPoint for Lessons

PowerPoint for Lessons. for educational use only. For more information contact: science.writer@mareposa.com. Pinnipeds: Seals true seals Sea lions, fur seals eared seals Walrus 35+ species globally Galápagos fur seal (40 – 140 lbs) Southern elephant seal (800 – 8,000 lbs)

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PowerPoint for Lessons

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  1. PowerPoint for Lessons for educational use only For more information contact: science.writer@mareposa.com

  2. Pinnipeds: • Seals true seals • Sea lions, fur seals eared seals • Walrus • 35+ species globally • Galápagos fur seal(40 – 140 lbs) • Southern elephant seal(800 – 8,000 lbs) • Differing life strategies: • Shore-based breeding • ice-based breeding • resident / migrating • Diet: fish, shellfish, squid, birds Steller sea lion - Prince William Sound, AK

  3. Fin-footed facts: • Dives to 1,700 m depthNorthern elephant seals • Dives of 1 ½ hoursWeddell seals • Bi-annual migrationsNorthern elephant seals swim 20 – 40,000 km / yr • Highly variable suckling period (lactation)1-3 years - Galápagos fur seal 30-40 % milk fat 4-8 days - Harp seal up to 60% milk fat Weddell seal sleeping in ice hole Ross Sea, Antarctica

  4. Pinnipeds in Oregon: • Harbor seals • Northern elephant seals • Steller sea lions • California sea lionsmales outside of breeding season • Very rare visitors: • Northern fur seals • Guadalupe fur seals

  5. Seguam Island, Aleutian Islands, AK July 1970 Stellersea lions

  6. ? ? ? ? ? ? ? Seguam Island, Aleutian Islands, AK July 2007 Steller sea lionThe largest of the ‘eared seals’ – otariids • Males:- 2,500 lbs defend territories June - August • Females: up to - 600 lbs

  7. For more information about Steller sea lions, students can read the profile about “Stella” the Steller sea lion at : http://www.sealtag.org/images/Stella.pdf

  8. The problem: Steller sea lion population 1970’s to 2007 170,000 Endangered Species Act listing & unexplained decline has led to severe restrictions on largest commercial fishery in US (Alaskan groundfish) Steller sea lions counts in Western Alaska 1970’s: > 170,000 2007: 45,000endangered 1970 2007 Source: NMFS

  9. Steller sea lion population 1970’s to 2007 170,000 Eastern Steller sea lions counts including Oregon, CA, WA, BC, SE-AK 1970: 20,000 2002: 46,000threatened Steller sea lions counts in Western Alaska 1970’s: > 170,000 2007: 45,000endangered 1970 2007 Source: NMFS

  10. How do scientists count sea lions? Sounds easy, right? ESA listing & unexplained decline:  severe restrictions on largest commercial fishery in US (Alaskan groundfish) Yo, watch out!

  11. Scientists use telemetry to study animals remotely Telemetry is the science and technology of measuring things remotely that allows information to be obtained by a wire, radio, satellite, data recorder or other device such as a tag.

  12. How Satellite Telemetry in Steller Sea Lions Works

  13. Temperature tells how the sea lion died A dead body is a cold body. A slow gradual decrease in temperature indicates death by natural causes.

  14. Temperature tells how the sea lion died A rapid decrease in temperature in a short time indicates death by a predator.

  15. Death by Starvation or Disease Death by Predation The tag stays in dead body that slowly cools. The tag comes out of the body into the cold water when dismembered by a predator.

  16. What have we learned? • From earlier research: • Scientsts know 70% of weaned* animals die before the age of 5, but they did not know how they were dying • Research results since 2005: • 36 young sea lions released with LHX tags in Prince William Sound • 12 animals died • How did they die? Mortality

  17. What have we learned? • Conclusion since 2005: • At least 11 of 12 died by predation • Transient killer whales are likely responsible for the majority of deaths in young Steller sea lions Evidence for killer whale predation: Mortality • Killer whales were video recorded in Resurrection Bay. • Killer whales typically dismember (break apart) their prey. • Researchers found a killer whale with 14 flipper tags (external markers) from Steller sea lions in its stomach.

  18. The Life History Transmitter • Scientists and engineers are designing a new LHX2 Tag • Half the size of the old LHX1 tag • Can detect births using the animal’s body temperature Productivity

  19. Temperature and Dive Pattern in A Sea Otter Productivity Temperature can be used to detect births.

  20. Population Ecology • A population is a group of individuals of the same species living in the same region. • Population ecology is the study of how populations change over time and interact with their environment.

  21. Population Ecology Change in Population = (Births – Deaths) + (Immigration – Emigration) • At the basic level, scientists studying animal population growth ask: • How many are born? • How many die? • How many animals move into the same region (immigration) ? • How many animals move out of the same region (emigration) ?          

  22. Carrying Capacity • A population’s size is limited by its carrying capacity: the maximum, stable population an environment can support over a long period of time. • The carrying capacity indicates how well the environment is able to support animals with food, habitat, territory, and other resources.

  23. Population Density • the number of animals per area • population density affects population growth due to the availability of resources ½ each ¼ each As numbers increase, the share of the food (or other resources) gets smaller.

  24. Aerial photos for estimating populations Counting all 45,000 animals would take forever, so scientists estimate the population size by counting a sub-sample of the population (yellow square).

  25. Mark Recapture • Another method for estimating population size • Scientists capture animals, mark them, and resample to see what percent of animals have marks. • http://www.biologycorner.com/flash/mark_recap.swf

  26. Engineers and Scientists Worked as a Team to Design the LHX Tag The scientist (customer) sets the criteria for the tag The engineer designs the tag (product)

  27. How are science and engineering different? Scientists ask questions and find answers to them by doing research to discover the answer. Engineers develop things (technology) to address human needs or “problems”.

  28. How do engineering and science compare? after http://www.sciencebuddies.org/science-fair-projects/project_engineering.shtml

  29. Engineering Process Cycle Plan, do, reflect, review from NASA: http://www.nasa.gov/audience/foreducators/plantgrowth/reference/Eng_Design_5-12.html

  30. The Engineering Process • Identify the need: • How can I design a ______ that will ______? For example, how can I design a transmitter that will float and be able to send a signal? • Identify criteria (requirements) and constraints (limitations): requirements: It must float 3 cm above the water. constraints: It must be stable in water, cannot tip.

  31. The Engineering Process • Brainstorm solution: Quicklysketch ideas as the group discusses ways to solve the problem • Plan: Draw a scale diagram of each idea (top, front, side and 3-versions).

  32. The Engineering Process • Create: Choose the best idea. Describe why, including criteria and constraints.* • Improve: Examine and evaluate the product based on the criteria and constraints.

  33. Criteria Design Specifications

  34. Design Constraint Table

  35. How many batteries? 5th-8th Apply the principles of buoyancy to design their own “transmitter”. Buoyancy : • is a force exerted by a fluid, that opposes an object's weight

  36. Picture of Buoyancy Setup

  37. Learning Procedure Students use the formula for the volume of a cylinder to calculate the water displacement due to buoyancy. Students use the water displacement weight to calculate the number of batteries (pennies) to put in the “tag” for a given amount of floatation. Students as engineers, test their calculations with the model Teachers and students engage in a discussion of tradeoffs.

  38. Formulas/Information • Volume of cylinder (V) = Pi r2 x height • Mass, m = pV • p = density of water 1g/cm3 • Weight of tube = 22.1g • Weight of battery 2.5g

  39. Electromagnetic Shielding 9th-12th Test the principles of electromagnetic shielding using a cell phone. Faraday’s Cage • external electrical field causes the charges to rearrange, which cancels the field inside http://en.wikipedia.org/wiki/File:Faraday_cage.gif

  40. Picture of Faraday’s Cage Setup

  41. Learning Procedure 1. Introduce electromagnetic radiation, how cell phones work, and Faraday’s cage. 2. Ask if radio waves can travel through tissue. Ask students how they would test this. 3. Ask students to predict what will happen to the signal strength (number of bars) of a transmitter in air, in a Faraday’s cage, and under saltwater. 4. Challenge students to think about how they would design a room that would prevent cell phone signals.

  42. Acknowledgements, Permits • Jo-Ann Mellish (Alaska Sea Life Center), Roger Hill (Wildlife Computers) • Photo credits: Alaska Dept. Fish & Game, Jason Waite • Funding through: • North Pacific Marine Research Program • The National Science FoundationNMFS Permits # 1034-1685, 881-1668

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