Marine Diversity

1. Marine Diversity Ocean Structure and Biodiversity

2. Oceans cover most of the Earth’s surface • The oceans influence global climate, team with biodiversity, facilitate transportation and commerce, and provide resources for us • They cover 71% of Earth’s surface and contain 97% of Earth’s surface water • Oceans influence the atmosphere, lithosphere, and biosphere

3. The oceans contain more than water • Ocean water is 96.5% water • Plus, ions of dissolved salts • Evaporation removes pure water and leaves a higher concentration of salt • Nutrients (nitrogen and phosphorus) • Dissolved gas • Oxygen is added by plants, bacteria, and atmospheric diffusion

4. Ocean water is vertically structured • Temperature declines with depth • Heavier (colder saltier) water sinks • Light (warmer and less salty) water remains near the surface • Temperatures are more stable than land temperatures • Water’s high heat capacity • It takes much more heat to warm water than air • Oceans regulate the earth’s climate • They absorb and release heat • Ocean’s surface circulation

5. Ocean water flows horizontally in currents • Currents are continuous, directed movements of ocean water generated by the forces acting upon it and they carry nutrients, heat and gasses. • Surface currents are driven by wind • Deep water currents are driven by density differences, heating and cooling, gravity, and wind • Pole-moving currents are warm water currents that move from the equator toward the north or south pole

6. Major Currents

7. Surface winds and heating create vertical currents • Upwelling = winds blow away from the coast and draws the vertical flow of cold, deep, nutrient rich water towards the surface • High primary productivity and lucrative fisheries • Downwellings = winds blow and push warm water toward the coast; colder, more dense water sinks

8. Salinity • The ocean is approximately 3-4% saline • 30-40 parts per trillion (ppt) • 1/1,000,000,000,000 • 30 to 40 ng / 1 L • Saline indicates the presence of ions including both mono- and polyatomic • Chloride, sodium, sulfate, magnesium, calcium, potassium and bicarbonate

9. Global Salinity

10. Fishing Practices & Regulations Here fishy, fishy, fishy!

11. Economic Importance of Aquatic Ecosystems • The economic importance of aquatic diversity is the estimate of the value of their ecological services which is $21 trillion a year. • At least 3.5 billion people depend on the seas for their primary source of food; this number could double to 7 billion in 2025.

12. Driftnets for schools of herring, sardines, mackerel, sharks • Longline fishing for tuna and swordfish • Trawling for pelagic fish and groundfish

13. Trawling • Bottom-trawling destroys communities • Likened to clear-cutting and strip mining

14. Fishing has industrialized • Factory fishing = highly industrialized, huge vessels use powerful technologies to capture fish in huge volumes • Even process and freeze their catches while at sea

15. Fishing practices kill nontarget animals • By-catch = the accidental capture of animals • Driftnetting drowns dolphins, turtles, and seals • Fish die from air exposure on deck • Banned or restricted by many nations • Longline fishing kills turtles, sharks, and albatrosses • 300,000 seabirds die each year

16. Emptying the oceans • We are placing unprecedented pressure on marine resources • Half the world’s marine fish populations are fully exploited • 25% of fish population are overexploited and heading to extinction • Total fisheries catch leveled off after 1998, despite increased fishing effort • It is predicted that populations of all ocean species we fish for today will collapse by the year 2048

17. We have long overfished • People began depleting sea life centuries ago • Some species hunted to extinction: Steller’s sea cow, Atlantic gray whale, Caribbean monk seal • Overharvesting of Chesapeake Bay oyster beds led to the collapse of its fishery, eutrophication, and hypoxia • Decreased sea turtle populations causes overgrowth of sea grass and can cause sea grass wasting disease

18. The total global fisheries catch has increased

19. Industrialized fishing depletes populations • Catch rates drop precipitously with industrialized fishing • 90% of large-bodied fish and sharks are eliminated within 10 years • Populations stabilize at 10% of their former levels • Marine communities may have been very different before industrial fishing • Removing animals at higher trophic levels allows prey to proliferate and change communities

20. Modern fishing fleets deplete marine life rapidly • Grand Banks cod have been fished for centuries • Catches more than doubled with immense industrial trawlers • Record-high catches lasted only 10 years

21. Oceans today contain only one-tenth of the large-bodied animals they once did

22. Several factors mask declines • Industrialized fishing has depleted stocks, global catch has remained stable for the past 20 years • Fishing fleets travel longer distances to reach less-fished portions of the ocean • Fleets spend more time fishing and have been setting out more nets and lines, increasing effort to catch the same number of fish • Improved technologies: faster ships, sonar mapping, satellite navigation, thermal sensing, aerial spotting • Data supplied to international monitoring agencies may be false

23. We are “fishing down the food chain” • Figures on total global catch do not relate the species, age, and size of fish harvested • As fishing increases, the size and age of fish caught decline • 10-year-old cod, once common, are now rare • As species become too rare to fish, fleets target other species • Shifting from large, desirable species to smaller, less desirable ones • Entails catching species at lower trophic levels

24. Consumer choices influence fishing practices • Buy ecolabeled seafood • Dolphin-safe tuna • Consumers don’t know how their seafood was caught • Nonprofit organizations have devised guides for consumers • Best choices: farmed catfish and caviar, sardines, Canadian snow crab • Avoid: Atlantic cod, wild-caught caviar, sharks, farmed salmon

25. Central Case: collapse of the cod fisheries • No fish has more impact on human civilization than the Atlantic cod • Eastern Canadians and U.S. fishermen have fished for cod for centuries • Large ships and technology have destroyed the cod fishery • Even protected stocks are not recovering

26. Cod are groundfish • They live or feed along the bottom • Halibut, pollock, flounder • Cod eat small fish and invertebrates • They grow to 60-70 cm long and can live 20 years • Inhabit cool waters on both sides of the Atlantic • There are 24 stocks (populations) of cod

27. To Protect and Serve • We can protect and sustain marine biodiversity by using laws, international treaties, and education. • First identify and protect species that are endangered and/or threatened. • Clean up aquatic environments

28. Why is it so hard? 1. Our human footprint is so large and is growing exponentially; 2. Damage to the ocean is not usually visible to the naked eye; 3. People view the ocean as an in-exhaustable resource; 4. The ocean is outside the legal jurisdiction of any one country.

29. We can protect areas in the ocean • Marine protected areas (MPAs) = established along the coastlines of developed countries • Still allow fishing or other extractive activities • Marine reserves = areas where fishing is prohibited (less than 0.3% of the ocean) • Leave ecosystems intact, without human interference • Improve fisheries, because young fish will disperse into surrounding areas

30. Reserves work for both fish and fisheries • Found that reserves do work as win-win solutions • Overall benefits included… • Boosting fish biomass • Boosting total catch • Increasing fish size • Benefits inside reserve boundaries included… • Rapid and long-term increases in marine organisms and decrease mortality and habitat destruction

31. How should reserves be designed? • 20-50% of the ocean should be protected in no-take reserves • How large? • How many? • Where? • Involving fishers is crucial fisheries in coming with these answers

32. Areas outside reserves also benefit • Benefits included… • A “spillover effect” when individuals of protected species spread outside reserves • Larvae of species protected within reserves “seed the seas” outside reserves • Improved fishing and ecotourism

33. Marine Management • There are a number of ways to manage marine fisheries more sustainably and protect marine biodiversity. • A country has jurisdiction over the ocean up to 200 miles from it’s coast. • Rather than protecting the marine environment, countries tend to promote fishing.

34. Integrated Coastal Management • Integrated Coastal Management (ICM) is an idea or management policy based on a community approach. • Private sector as well as the public sector work together to identify problems and share the burden of restoration or management.

35. Managing Fisheries • Fishery Regulations: • set catch limits well beyond maximum sustainable yield • improve monitoring and enforcement • Economic Approach: • reduce or eliminate subsidies • charge fees for harvesting fish and shellfish from public areas • certify sustainable fisheries

36. More Management • Protected Areas: • establish “no-fishing” zones • establish more reserves • rely on integrated coastal management • Consumer Education: • label sustainably harvested fish • educate about overfished and endangered species

37. Management (cont.) • Bycatch: • streamline fishing techniques and tools • Aquaculture: • restrict coastal locations for fish farms • control pollution (CWA) • depend on herbivorous fish species • Non-native Invasions: • kill organisms in ship ballast water, filter ballast water or dump in open sea

38. Legislation: Each group will discuss the event and the impact 1946 - International Convention of the Regulation of Whaling 1970 - US ban on whaling and importation of whale products 1972 - US Marine Mammel Protection Act 1973 - US Endangered Species Act 1975 - Convention on International Trade in Endangered Species (CITES) 1979 - Global Treaty on Migratory Species

39. Revamping Ocean Policy • Two recent studies called for an overhaul of U.S. ocean policy and management. • Develop unified national policy. • Double federal budget for ocean research. • Centralize the National Oceans Agency. • Set up network of marine reserves. • Reorient fisheries management towards ecosystem function. • Increase public awareness.

40. MANAGING AND SUSTAINING MARINE FISHERIES • There are a number of ways to manage marine fisheries more sustainably and protect marine biodiversity. • Some fishing communities regulate fish harvests on their own and others work with the government to regulate them. • Modern fisheries have weakened the ability of many coastal communities to regulate their own fisheries.

41. Solutions Managing Fisheries Fishery Regulations Set catch limits well below the maximum sustainable yield Improve monitoring and enforcement of regulations Bycatch Use wide-meshed nets to allow escape of smaller fish Use net escape devices for sea birds and sea turtles Ban throwing edible and marketable fish back into the sea Economic Approaches Sharply reduce or eliminate fishing subsidies Charge fees for harvesting fish and shellfish from publicly owned offshore waters Certify sustainable fisheries Aquaculture Restrict coastal locations for fish farms Control pollution more strictly Depend more on herbivorous fish species Protected Areas Establish no-fishing areas Establish more marine protected areas Rely more on integrated coastal management Nonnative Invasions Kill organisms in ship ballast water Filter organisms from ship ballast water Dump ballast water far at sea and replace with deep-sea water Consumer Information Label sustainably harvested fish Publicize overfished and threatened species Fig. 12-7, p. 261

42. The graph to the right shows the decline in the catch of groundfish (such as cod, haddock, and flounder) from Georges Bank from 1965 to 1995. This decline in the fish harvest resulted in the closure of large portions of the fishery. Identify the five-year period during which the greatest rate of decline in the fish harvest took place. For that five-year period, calculate the rate of decline in the fish harvest, in metric tons per year. Show clearly how you determined your answer.

43. Choose any TWO commercial fishing practices from the list below. For each of your choices, describe the practice and explain the role it plays in the depletion of marine organisms. • Bottom trawling • Long-line fishing • Using drift nets/gill nets/purse seines • Using sonar •  Identify one international regulation or United States federal law that applies to the harvesting of marine food resources and explain how that regulation or law helps to manage marine species. •  The oceans of the world are often referred to as a commons. Give an example of one other such commons, explain how human activities affect that commons, and suggest one practical method for managing that commons.

44. Using the APES Rubric • Let’s score your response