about the research paper:

Transcription

1 Environmental Issues & Problems ENV 150 Guillaume Mauger Quiz # 1 Today: Quiz Review Discuss research paper Topic: Fisheries Collapse Reminder: Due THURS: Service-Learning Agreement REMEMBER TO TURN IN YOUR 2nd FORM TO PATTI!!! Quiz # 1 about the research paper: There are four assignments that lead up to the final paper 1. Paper proposal Done 2. Annotated bibliography Due 11/5 3. Rough draft Due 11/19 4. Draft for Peer Review - in class: 12/10 ( Final Draft Due on 12/15)

2 research paper topics Fisheries Collapse note: Thursday s s class will be held in the library. videos: Reading Scientific Papers What is a scientific paper? what about peer review? Reading Scientific Papers What is a scientific paper? what about peer review? How are they written / organized? scientific writing is not a particularly creative writing style: it s concise, predictable, detailed, and strives for clarity in meaning.

3 example abstract: Reading Scientific Papers Reading Scientific Papers General questions to ask: What is the goal of the research? Why is this an important question? Where does their data come from? Big Picture How do they manipulate / interpret the data? What is the conclusion? Does it make sense? Does it fit with your prior conception? Specifics Fisheries Collapse A comment from a parent left at the Birch Aquarium at Scripps: "I brought my children to the aquarium so they could see the things I saw at the seashore as a child." Marine Biodiversity, patterns 1. Greatest diversity exists in coral reefs, estuaries, and on ocean floor. 2. Biodiversity is greatest near coasts 3. Biodiversity is greatest near ocean floor than on the surface.

4 Marine Biodiversity, value Marine Biodiversity, losses Fisheries Collapse: Estimated value of marine ecosystem services: $21 trillion / yr Source: Meyers and Worm, Nature, 2003 Marine Biodiversity, losses Fisheries Collapse: Marine Biodiversity, losses Fisheries Collapse: 90% of Large Predatory Fish populations have disappeared Facing Extinction within your lifetime: 34% of known marine fish species, and 71% of known freshwater fish species Source: IUCN Red List Source: Meyers and Worm, Nature, 2003 Source: Meyers and Worm, Nature, 2003

5 Marine Biodiversity, losses Fisheries Collapse: Species peak peak 1992 decline year catch catch (m tons) % change Pacific herring % Atlantic herring % Atlantic cod % South African Pilchard % Haddock % Peruvian anchovy % Polar cod % Cape hake % Silver hake % Greater yellow croaker % Atlantic redfish % Cape horse mackerel % Chub mackerel % Blue whiting % South American pilchard % Alaska pollock % N Pacific hake % Japanese pilchard , % Marine Biodiversity Reasons for the loss 1. Invasives 2. Climate change - Ocean acidification, sea level rise, ocean warming 3. Pollution and Toxics 4. Loss of habitat - especially coastal: coral reefs, mangroves, estuaries, etc. 5. Overfishing Overfishing Consequences of overfishing 1. Changes in marine food web Worldwide: Trawled Area = 150 x annual rainforest clear-cuts clear-cutting the forest to catch a squirrel Fishing down the marine food web Pew Oceans Commission

6 Biomass Pyramid Consequences of overfishing 2. Habitat Destruction & bycatch Method Dredges Gillnets bottom Gillnets midwater Longlines bottom Longlines pelagic Pots and traps Trawls bottom Trawls midwater Worst Fishing Methods (worst) Dredge Towed metal bag wide, 2400 lbs Scallops, clams, oysters, shellfish

7 (worst) (worst) Bottom gillnet 350 long anchored net Sardines, goosefish, cod, pollock, flounder, salmon Significant bycatch - turtles, dolphins Bottom trawl Towed net with weights 200 wide, 40 high Shrimp, sole, flounder, rockfish Can disrupt seafloor Purse Seine Encircles a school of fish Bottom of net closed Hauled onboard / brought near surface Schooling fish: sardines, tuna Significant bycatch (best) (best) Pelagic longline 1-50 miles long Tuna, swordfish Bycatch: sharks, turtles, seabirds Hook and Lining Lure fish with baited lines Surface dwellers: tuna, mahi mahi Bottom dwellers: cod Minimal bycatch Pots and Traps Wire or wood, baited cages Crab, lobster, rockfish Bycatch: marine mammals can become entangled in the rope connecting the cage to a buoy Trolling Lure fish with towed baited lines Surface dwellers: tuna, mahi mahi Minimal bycatch

8 Challenges to Fisheries preservation 1. Extremely rapid human expansion (most of world s population lives near coasts = finite resource vs increasing demand) 2. Damage isn t readily visible (underwater) 3. Seen as an inexhaustible resource Unless the order of nature is overthrown, for centuries to come our fisheries will continue to be fertile. 4. No clear jurisdiction in international waters Solutions Endangered Species Act» Whales, seals, sea lions, sea turtles Marine Protected Areas» Partial protection. Some commercial fishing allowed Marine Reserves» Within 1-2 years, population densities increased 91%, average fish size up 31%, species diversity rose 20%» Biggest fish caught along borders of reserves» NOTE: only 1% of oceans are protected. Need ~30% Fisheries Management» Goal: set limits to reduce catch to sustainable yield» Current subsiies: $124 billion spent for $70 billion earned» US Magnuson-Stevens Reauthorization Act, 2006