What the threats to the oceans?

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1 Conservation of the marine environment Dr. Katrina Mangin Department of Ecology and Evolutionary Biology Lion steak Eagle Pie What the threats to the oceans? Overfishing Coastal development and habitat loss Runoff from land (fertilizers, oil, sediment) Pollution and garbage in sea Invasive species Climate Change (seas are warming) Consequences Loss of biodiversity Human health risks Mercury in fish (power plants) Swimming in dirty water (fertilizers) Loss of fresh water on islands (SW intrusion, pollution) Habitat destruction/loss 50% US population lives on coast (development) Coral reefs dying (global warming) Ocean floor destroyed (trawling) 150 dead zones in 2004, double since 1990 (UN data)( fertilizers) What can we do? Stop overfishing! Regulate coastal development and fishing Identify threats & culprits Document loss of marine habitat and diversity Establish marine reserves 1

2 What can we do? Involve all stakeholders in the solutions Educate next generation so that they care Support conservation efforts with your $$ and votes Four examples Tuna fishery Worldwide decline in predatory fish Gulf of California -shrimp fishery Gulf of California - working with fishermen Tokyo fish market 5 million pounds of seafood per day 400 different types of seafood Imports from 60 countries on 6 continents 2

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4 $65-$85 per kg fresh tuna - whole sale Tuna is the most traded fishery in the world 3 million tons of catch per year $6 billion per year Europe is top buyer, followed by US for canned tuna Heinz dominates 50% of the market The tuna dolphin controversy 7 million dolphins have been killed by tuna fishing since the late 1950s Dolphins on surface, yellowfin tuna below Unique relationship between tuna & dolphin - exploited since 1950s Fishers use dolphins to track and chase the tuna, then encircle both with nets (purse seines), haul in both, killing the dolphins, and saving the tuna. Eastern Tropical Pacific Tuna Fleet: 1950s dolphin sets on tuna began sets on dolphins (mile long nets and hydraulics introduced) sets on dolphins (helicopters and speed boats introduced) ,673 tons of tuna caught ,426 tons of tuna caught dolphin sets = setting nets around dolphins in order to catch yellowfin tuna 4

5 Three species of dolphin in eastern tropical pacific are officially listed as depleted * northeastern offshore spotted dolphin eastern spinner dolphin coastal spotted dolphin History of dolphin safe tuna label 1980s: US tuna fleet can not encircle dolphins US embargo against other countries: no dolphin setting on tuna 1990: label on tuna cans * MMPA (Marine Mammal Protection Act) Dolphin safe tuna Mexico protested embargo: product is not environmentally harmful 1995: Mexico and other nations can sell dolphin-set tuna, under the dolphin safe label. Set minimum levels for dolphin kills Evans, US commerce secretary: dolphin safe label weakened again: dolphin sets OK as long as observers on ships. Judge upholds definition of dolphin-safe tuna label Thursday, April 10, 2003 Printable Version This Article (04-10) 16:55 PDT SAN FRANCISCO (AP) -- A federal judge on Thursday upheld the definition of the dolphin-safe tuna label and barred the Bush administration from altering it. On Dec. 31, the Commerce Department announced that tuna caught by fishermen encircling dolphins with nets may be imported into the United States and bear the dolphin-safe label if observers certify that no dolphins were killed or seriously injured in the process. Environmentalists sued. Dolphin safe tuna Most tuna fishing is still done with dolphin sets US no longer has tuna fleets In EU, no dolphin safe labels are required. Dolphin sets vs. Log Fishing for Tuna * 1000 nets set on dolphin (purse seines) : 500 dolphins 52 Billfish 10 sea turtles 0 sharks 1000 nets using logs ( dolphin-safe ): 2 dolphins 654 billfish 102 sea turtles 13,958 sharks * Data from International Tropical Tuna Commission 5

6 Blue Planet dvd Rapid worldwide decline of predator fish communities, Myers R.A. & B. Worm, Nature v. 423, 15May2003 What they concluded: Only 10% of large, predatory fish are left in the world s oceans. Black=bigeye Yellow=yellowfin Blue= bluefin Green=albacore White=billfish Decline in all oceans 1950s-2000 (Myers & Worm 2003) Gulf of California High biodiversity and endemism 6000 named macrofauna (visible to eye) 4853 invertebrates endemics: 128 invertebrates, 14 vertebrates 7 species of sea turtles 24 marine mammals (Vaquita (harbor porpoise) Second most diverse sea in the world Why do diverse? Gulf of California Colorado River Delta water and nutrients Long narrow sea - isolated for a long time Many islands - mini Galapagos Extreme tides Highly seasonal (desert) sea Many habitat types: Shallow reefs and bays, deep trenches, coquina reefs Relatively pristine 6

7 Gulf of California All marine mammals threatened - Vaquita found only in gulf (endemic*) 11 at risk species of fish (5 large bass, endemic) All 7 turtle species threatened or endangered Shrimp fishery Trawling for shrimp For each pound of shrimp, ten pounds of bycatch * Scraping of ocean floor by trawling * bycatch= incidental catch that is thrown away 7

8 Trawling for shrimp Working with the fishermen Murex fishery in Gulf of California Black Murex (Hexaplex(muricanthus) nigritus) Larval settlement in the marine environment is not random. Commerical divers in Puerto Penasco, Sonora, Mexico. These divers collect murex snails in the summer, along with several other species. Settlement cues include chemicals, light, dark, depth, and substrate type. 8

9 Shifting Baselines Swordfish, 1940, coastal Peru antiquefishingreels.com/ What is a shifting baseline? Shifting baselines are the chronic, slow, hard-to-notice changes in things Ex) If your ideal weight used to be 150 pounds and now it's 160, your baseline -- and your waistline -- has shifted. Baselines Shifted Baseline = Lowered Standard shifting baselines video Baselines are used to determine the health of ecosystems The ideal baseline for any given habitat would be what was there before human impact Other UA marine science Marine Discovery (ECOL 450) Fall 2004 Marine Biology (ECOL 183) spring 2005 Galapagos Marine Ecology (ECOL 496O) Oceanography (GEOS 212 & 412) Invertebrate Paleontology (GEOS) Marine & Freshwater Algae Ecological Anthropology (ANTHRO) 0thers Marine Science minor coming soon 9