1. Question of the day:
What are some examples of human impacts upon the oceans?
What are some ways to alleviate these impacts?

2. Case Study: Depleting Bluefin Tuna Stocks
Being fished at 4 times the sustainable level
Economic value places it in danger
Conservation measures protect the species
Overfishing
Harvesting of fishes faster than they can reproduce
30% of worldwide fishes
80% of commercial fish stocks in US
If overfishing and pollution aren’t curbed, populations of all harvested seafood species will be gone by 2048

3. Blue Fin Tuna video clip

4. Human Impacts on the Ocean
Fisheries and aquaculture
Marine shipping
Marine pollution
Coastal development
Offshore mining
Global climate change
In 2008, less than 4% of ocean remained unaffected by human activities; 41% serious harm

5. Human Impacts on the Ocean
Marine Pollution and Deteriorating Habitat
Paradox: ocean provides food but is used as dumping ground
Pollution increasingly threatens fisheries
80% of ocean pollution comes from land activities

6. Human Impacts on the Ocean

7. Human Impacts on the Ocean7

8. Overfishing World Fisheries Valuable food resources
90% of world’s catch is fishes,
6% is clams, oysters, squid, octopus, and other mollusks
3% is crustaceans: lobsters, crabs, shrimp
1% is marine algae
World’s Annual Harvest
million tons
million tons

9. Overfishing Problems and Challenges for the Fishing Industry
No nation has legal claim to open ocean
Resources are susceptible to overuse and degradation (Tragedy of the Commons)
Many species have been harvested to the point where their numbers are severely depleted
Unstable for marine species that rely on them as part of food web
At least 75% of world’s fish stocks are exploited, overexploited or depleted
Growing human population requires protein
Technological advances allows efficient catch, removing all fish from an area
25% of all is bycatch (unintentionally caught, then discarded)

10. What a Scientist Sees

11. Human impacts past 5 years
HW check and discussion

12. Aquaculture Impacts Aquaculture
Fish farming: growing of aquatic organisms for human consumption
Fresh and marine water
HDCs harvest more from open ocean
Developing nations harvest more from aquaculture
Abundant supply of cheap labor
Limit to harvest is the area available for farming
Fish farms have dense populations
Lots of polluting waste
Cause net loss of wild fish (raised fish tend to be carnivorous)
Ocean ranching: deep-water, off-shore aquaculture
Doesn’t harm coastline, but less oversight

13. Aquaculture cage farming

15. Ocean Dumping Shipping, Ocean Dumping, Plastic Debris
Millions of ships dump oily ballast and waste
MARPOL bans marine pollution from shipping industry
Not well enforced
Ocean Dumping Ban Act
Cities used to dump sewage into ocean, disease-causing organisms contaminated shellfish
Plastic waste
Doesn’t degrade, just breaks up into smaller pieces
Pacific Garbage Patch, 2009, 2x size of Texas
Plastic pieces entangle marine mammals and birds
Filter feeders ingest plastic pieces, carriers of PCBs

16. Crazy Ocean Dumping Stories
Wired Science video clip

17. Plastics and Debris
Great Pacific Garbage Patch Video clip from Wired Science

18. Coastal development Coastal Development
Alters or destroys coastal ecosystems:
Mangroves, salt marshes, sea grass beds, coral reefs
Coastal areas overdeveloped, highly polluted, overfished
Coastal management plans are inadequate
Biggest problem is human population size
60% of world’s population lives within150 km (93 mi) of coastline
As much as 75%, by 2025

19. Human Impacts on Coral Reefs
25% of world’s corals are at high risk
Silt washing downstream from clear-cut forests is smothering reefs
High salinity from freshwater diversion projects
Overfishing of top predators
Damage by tourists
Pollution from ocean dumping and coastal pollution
Bleaching = stressed corals expel zooxanthellae

20. What a Scientist Sees- Coral Bleaching

21. Coral Bleaching

22. Offshore Extraction of Mineral and Energy Resources
Large deposits of minerals lie under the sea floor
Manganese nodules -
mining would adversely affect sea life and market value would not cover expense of mining
Disputes over deposits under international waters
Petroleum -
Major source of energy
Major threat to fishing

23. Manganese deposits

24. Oil Spills
Student research and presentations

25. Climate Change Incomplete understanding, unanticipated effects
There could be a disruption of the ocean conveyor belt, which transports heat around the globe
Climate warming could shut down conveyor belt within a decade
Could cause major cooling in Europe
Major warming in other parts of the world
Would not sequester CO2 into ocean  more CO2 in atmosphere  more warming  more weakening of belt

26. Global Climate Change
What are some of the harmful environmental effects associated with the fishing industry? With aquaculture?
How does the widespread use of plastics contribute to ocean pollution?
How might the effect of global climate change on the ocean alter the global climate?

27. STOP

28. Addressing Ocean Problems
Learning Objectives:
Describe international initiatives that address problems in the global ocean
Explain goals associated with correcting ocean problems in the future

29. Addressing Ocean Problems
Problems are complex and require complex solutions
UN Convention on the Law of the Sea (UNCLOS) countries have ratified
Protecting ocean resources
UN fish stocks agreement
Regulates marine fishing
Fishery Conservation and Management Act
Protect essential fish habitat for 600 species
Reduce overfishing, rebuild populations, minimize bycatch
Fishing quotas, restrictions on fishing gear, limits on number of fishing boats, closure of fisheries during spawning

30. Addressing Ocean Problems
Future Actions
US Commission on Ocean Policy-2004 report
Create a new ocean policy to improve decision making-
Consolidate agencies
Strengthen science and generate information for decision makers
Need for high quality research
Enhance ocean education to instill in citizens a stewardship ethic
Environmental education should be part of the curriculum at all levels, including strong marine component

31. Addressing Ocean Problems
Future Actions
Establishment of “no-take” reserves
Substantial reduction of fishing fleet
Remove subsidies of fishing industry
Adopt an ecosystem-based approach to manage ocean environments
Focus on preserving the health and function of the entire marine ecosystem
Establish networks of fully protected marine reserves
Less than 5% of US marine environments have been protected, with great success

32. Addressing Ocean Problems

33. Case Study The Dead Zone in the Gulf of Mexico
N and P runoff from Mississippi river
Algae grow rapidly, dead algae sink to bottom and decompose, deplete water of O2 (hypoxic zone)
Only anaerobic bacteria thrive there
March to September, worst June-August
Climate change is making dead zones worse, even without runoff
Threaten biodiversity and coastal fisheries

34. Case Study

35. Global Climate Change
Which international treaties aim to protect ocean resources?
What are the main goals recommended by the US Comission on Ocean Policy?