1. Sustaining Aquatic Biodiversity and Ecosystem Services11
Sustaining Aquatic Biodiversity and Ecosystem Services

2. Case Study: The Plight of Sea Turtles
All seven species in danger through:
Trawler fishing
Destroyed many coral gardens that are turtle feeding grounds
Turtles hunted for leather
Eggs taken for food
Pollution of ocean water

3. Hawksbill 89 centimeters Loggerhead 119 centimeters Flatback
Olive ridley
76 centimeters
Figure 11-1: There are seven species of sea turtles. All but the flatback are found in U.S. waters.
Green turtle
124 centimeters
Leatherback
188 centimeters
Kemp’s ridley
76 centimeters
Fig. 11-1, p. 248

4. 11-1 What Are the Major Threats to Aquatic Biodiversity and Ecosystem Services?
Aquatic species and the ecosystem and economic services they provide are threatened by:
Habitat loss, invasive species, pollution, climate change, and overexploitation
All made worse by the growth of the human population and resource use

5. We Have Much to Learn about Aquatic Biodiversity
We have explored about 5% of the oceans
Greatest marine biodiversity
Coral reefs, estuaries, and deep-ocean floor
Biodiversity is higher
Near the coast than in the open sea
In the bottom region of the ocean than the surface region

6. Human Activities Are Destroying and Degrading Aquatic Habitat
Marine
Coral reefs
Mangrove forests
Seagrass beds
Ocean acidification
Freshwater
Dams

7. Figure 11. 2: Natural capital degradation
Figure 11.2: Natural capital degradation. These photos show an area of ocean bottom before (left) and after (right) a trawler net scraped it like a gigantic bulldozer. Question: What land activities are comparable to this?
Fig. 11-2, p. 250

8. Invasive Species Are Degrading Aquatic Biodiversity
Threaten native species
Disrupt and degrade whole ecosystems
Blamed for about two-thirds of all fish extinctions since 1900
Example
Lionfish in the Atlantic

9. Figure 11-3: The common lionfish has invaded the eastern coastal waters of North America, where it has few, if any, predators.
Fig. 11-3, p. 251

10. Population Growth and Pollution Can Reduce Aquatic Biodiversity
80% of all humans living along coasts
Nitrates and phosphates, mainly from fertilizers, enter water
Leads to eutrophication
Toxic pollutants from industrial and urban areas
Plastics
Ocean garbage

11. Climate Change Is a Growing Threat
Sea levels will rise and aquatic biodiversity is threatened
Coral reefs
Swamp some low-lying islands
Drown many highly productive coastal wetlands
Warmer ocean water stresses phytoplankton

12. Overfishing and Extinction: Gone Fishing, Fish Gone
Fishery – concentration of a particular wild aquatic species suitable for commercial harvesting in a specific area
Fishing key factor in the depletion of up to 80% of the population of some wild fish species in only years
Trawlers
Destroy ocean bottom habitat

13. Overfishing and Extinction: Gone Fishing, Fish Gone (cont’d.)
Purse-seine fishing
Can kill dolphins
Long-lining
Kills large numbers of sea turtles, dolphins, and seabirds
Drift net fishing
Large bycatch

14. Overfishing and Extinction: Gone Fishing, Fish Gone (cont’d.)
Fishprint – area of ocean needed to sustain the fish consumption of an average person, nation, or the world
Overfishing leads to commercial extinction
Commercially valuable fish become scarce
Bluefin tuna ranching
Some marine mammals are also threatened due to overfishing

15. Fish farming in cage
Trawler fishing
Sonar
Spotter airplane
Purse-seine fishing
Drift-net fishing
Float
Buoy
Fish caught by gills
Long line fishing
lines with hooks
Figure 11-5: Major commercial fishing methods used to harvest various marine species, along with some methods used to raise fish through aquaculture.
Deep sea aquaculture cage
Stepped Art
Fig. 11-5, p. 254

16. 900,000
800,000
700,000
600,000
500,000
Fish landings (tons)
400,000
1992
300,000
Figure 11-7: Natural capital degradation. This graph illustrates the collapse of Newfoundland’s Atlantic cod fishery.
200,000
100,000
1900
1920
1940
1960
1980
2000
Year
Fig. 11-7, p. 255

17. Figure 11-8: Bluefin tuna ranching: These bluefin tunas have been corralled in an underwater pen and will be fattened for slaughter to make sushi.
Fig. 11-8, p. 256

18. Case Study: The Great Jellyfish Invasion
Most jellyfish feed on zooplankton, fish eggs, small fish, and other jellyfish
Often found in blooms of thousands of individuals
Numbers of blooms rising in recent years
Overfishing of species that prey on jellyfish
Excessive nutrients in land runoff
Warmer waters

19. Figure 11-9: The lions mane is the largest of the roughly 1,500 known jellyfish species. It can be as wide as a full-size school bus and about 3 times as long.
Fig. 11-9, p. 257

20. Case Study: Why Should We Protect Sharks?
Sharks are keystone species
If they become extinct, their ecosystems will suffer
For every shark that injures a person, people kill about 1.2 million sharks
32% of open-ocean shark species are threatened with extinction

21. Figure 11-10: The threatened whale shark (left), which feeds on plankton, is the largest fish in the ocean and is quite friendly to humans. The scalloped hammerhead shark (right) is endangered.
Fig , p. 257

22. Extinction of Aquatic Species Is a Growing Threat
Biological extinction
Overfishing, water pollution, wetlands destruction, excessive removal of water from lakes and rivers
34% of marine species are threatened
71% of freshwater species are threatened
How are we protecting sea turtles?

23. Figure 11-11: This endangered loggerhead turtle is escaping a fishing net equipped with a turtle excluder device (TED).
Fig , p. 258

24. 11-2 How Can We Protect and Sustain Marine Biodiversity?
We can help to sustain marine biodiversity by:
Using laws and economic incentives to protect species
Setting aside marine reserves to protect ecosystems and ecosystem services
Using community-based integrated coastal management

25. Laws, Treaties, and Economic Incentives Can Help Sustain Aquatic Biodiversity
Human ecological footprint and fishprint are expanding
Much of the damage in the ocean is not visible
The oceans are incorrectly viewed as an inexhaustible resource
Most of the ocean lies outside the legal jurisdiction of any country

26. Laws, Treaties, and Economic Incentives (cont’d.)
Some examples:
1975 Convention on International Trade in Endangered Species
1979 Global Treaty on Migratory Species
U.S. Endangered Species Act of 1973
U.S. Whale Conservation and Protection Act of 1976
1995 International Convention on Biological Diversity

27. Marine Sanctuaries Protect Ecosystems and Species
Offshore fishing
Exclusive economic zones for countries
200 nautical miles
High seas governed by treaties that are hard to enforce
Law of the Sea Treaty
Misused
Marine protected areas (MPAs)
Protected from human activities

28. Establishing a Global Network of Marine Reserves: An Ecosystem Approach
Closed to:
Commercial fishing
Dredging
Mining and waste disposal
Core zone
No human activity allowed
Less harmful activities allowed
Example: recreational boating and shipping

29. Establishing a Global Network of Marine Reserves (cont’d.)
Fully protected marine reserves work fast
Fish populations double
Fish size grows
Reproduction triples
Species diversity increase by almost one- fourth
Cover less than 1% of world’s oceans
Marine scientists want 30-50%

30. Climate change and oil drilling Overfishing Overfishing
Coral bleaching
Trawler fishing
Mediterranean Sea
ATLANTIC OCEAN
PACIFIC OCEAN
PACIFIC OCEAN
INDIAN OCEAN
Figure 11-13: Natural capital: Ten marine hotspots—threatened areas, including coral reefs, and threatened fisheries that provide vital ecosystem services and that marine scientists say should be fully protected from harmful human activities.
Trawler fishing
Potential ocean floor mining
Climate change
Fig , p. 261

31. Restoration Helps to Protect Marine Biodiversity but Prevention Is the Key
Japan’s attempt
Seeding reef with new corals
Problems that cause degradation need to be addressed
Integrated coastal management
Community-based sustainability movement

32. Figure 11-14: Severe bleaching of coral near Kanton Island in the South Pacific (left), and an example of the recovery of coral in a protected area near the island (right).
Fig , p. 263

33. 11-3 How Should We Manage and Sustain Marine Fisheries?
Sustaining marine fisheries will require:
Improved monitoring of fish and shellfish populations
Cooperative fisheries management among communities and nations
Reduction of fishing subsidies
Careful consumer choices in buying seafood

34. Estimating and Monitoring Fishery Populations Is the First Step
Maximum sustained yield (MSY)
Traditional approach
Projects maximum annual harvest without causing population drop
Optimum sustained yield (OSY)
Attempts to account for interactions among species
Multispecies management

35. Estimating and Monitoring Fishery Populations Is the First Step (cont’d.)
Large marine systems
Using large complex computer models
Precautionary principle
Sharply reducing fish harvests
Closing overfished areas

36. Some Communities Cooperate to Regulate Fish Harvests
Community management of the fisheries
Co-management of the fisheries with the government
Government sets quotas for species and divides the quotas among communities
Limits fishing seasons
Regulates fishing gear

37. Government Subsidies Can Encourage Overfishing
Governments spend over 30 billion dollars per year subsidizing fishing
Often leads to overfishing
Discourages long-term sustainability of fish populations

38. Consumer Choices Can Help to Sustain Fisheries and Aquatic Biodiversity
Need labels to inform consumers how and where fish was caught
1999 – Marine Stewardship Council (MSC)
Certifies sustainably produced seafood
What is the proper use of sustainable aquaculture?

39. Solutions Managing Fisheries Fishery Regulations Economic Approaches
Bycatch
Fishery Regulations
Use nets that allow escape of smaller fish
Set low catch limits
Improve monitoring and enforcement
Use net escape devices for seabirds and sea turtles
Economic Approaches
Reduce or eliminate fishing subsidies
Aquaculture
Certify sustainable fisheries
Restrict coastal locations of fish farms
Protect Areas
Establish no-fishing areas
Improve pollution control
Figure 11-16: There are a number of ways to manage fisheries more sustainably and protect marine biodiversity. Questions: Which four of these solutions do you think are the best ones? Why?
Establish more marine protected areas
Nonnative Invasions
Consumer Information
Kill or filter organisms from ship ballast water
Label sustainably harvested fish
Publicize overfished and threatened species
Clean aquatic recreation gear
Fig , p. 264

40. 11-4 How Should We Protect and Sustain Wetlands?
We can maintain the ecosystem and economic services of wetlands by protecting remaining wetlands and restoring degraded wetlands

41. Coastal and Inland Wetlands Are Disappearing around the World
Wetlands have been disturbed for centuries
Sea level rise
Will inundate coastal wetlands

42. We Can Preserve and Restore Wetlands
Laws for protection
Zoning laws steer development away from wetlands
In U.S., a federal permit is required to fill wetlands greater than three acres
Mitigation banking
Can destroy wetland if one is created of equal area
Ecologists argue that this as a last resort

43. Figure 11-17: This human-created wetland is located near Orlando, Florida (USA).
Fig , p. 266

44. Case Study: Can We Restore the Florida Everglades?
Damage in the 20th century
Drained
Diverted
Paved over
Nutrient pollution from agriculture
Invasive plant species
1947 – Everglades National Park was an unsuccessful protection project

45. Case Study: Can We Restore the Florida Everglades? (cont’d.)
1990 – Comprehensive Everglades Restoration Plan (CERP)
Restore curving flow of ½ of Kissimmee River
Remove canals/levees in strategic locations
Flood farmland to create artificial marshes
Create 18 reservoirs to create water supply for lower Everglades and humans
Recapture Everglades water flowing to sea and return it to Everglades
Already weakened by Florida legislature

46. Figure 11-18: Florida’s Everglades is the site of the world’s largest ecological restoration project—an attempt to undo and redo an engineering project that has been destroying this vast wetland and threatening water supplies for south Florida’s rapidly growing population.
Fig , p. 267

47. 11-5 How Should We Protect and Sustain Freshwater Lakes, Rivers, and Fisheries?
Freshwater ecosystems are strongly affected by human activities on adjacent lands, and protection of these ecosystems must include protection of their watersheds

48. Freshwater Ecosystems Are in Jeopardy
40% of world’s rivers are dammed
Many freshwater wetlands destroyed
Invasive species
Overfishing
Human population pressures

49. Case Study: Can the Great Lakes Survive Repeated Invasions by Alien Species?
Collectively, world’s largest body of freshwater
Invaded by at least 162 nonnative species
Sea lamprey
Zebra mussel
Quagga mussel
Asian carp

50. Figure 11.20: These zebra mussels are attached to a water current meter in Lake Michigan.
Fig , p. 268

51. Figure 11-21: Asian carp may be the next major invasive species to threaten the Great Lakes.
Fig , p. 269

52. Managing River Basins Is Complex and Controversial
Columbia River – U.S. and Canada
119 dams
Dams
Provide hydroelectric power
Provide irrigation water
Hurt salmon

53. Figure 11-22: Rivers provide some important ecosystem services
Figure 11-22: Rivers provide some important ecosystem services. Questions: Which two of these services do you believe are the most important? Why?
Fig , p. 270

54. We Can Protect Freshwater Ecosystems By Protecting Watersheds
Freshwater ecosystems protected through:
Laws
Economic incentives
Restoration efforts
Wild rivers and scenic rivers
1968 National Wild and Scenic Rivers Act

55. Figure 11-23: The upper St. Croix River, flowing on the border between Minnesota and Wisconsin, was one of the first eight rivers to be designated a national wild and scenic river. It hosts a rich diversity of plant and animal species that are protected from riverside development and other harmful human activities.
Fig , p. 270

56. Freshwater Fisheries Need Better Protection
Sustainable management
Support populations of commercial and sport fish species
Prevent overfishing
Reduce or eliminate invasive species

57. 11-6 What Should Be Our Priorities for Sustaining Aquatic Biodiversity?
Sustaining the world’s aquatic biodiversity requires:
Mapping it
Protecting aquatic hotspots
Creating large and fully protected marine reserves
Protecting freshwater ecosystems
Restoring degraded coastal and inland wetlands

58. We Can Use an Ecosystem Approach to Sustain Aquatic Biodiversity
Complete the mapping of the world’s aquatic biodiversity
Identify and preserve aquatic diversity hotspots
Create large and fully protected marine reserves
Protect and restore the world’s lakes and rivers

59. We Can Use an Ecosystem Approach to Sustain Aquatic Biodiversity (cont’d.)
Ecological restoration projects worldwide
Make conservation financially rewarding

60. Three Big Ideas
The world’s aquatic systems provide important economic and ecosystem services
Scientific investigation of these poorly understood ecosystems could lead to immense ecological and economic benefits
Aquatic ecosystems and fisheries are being severely degraded by human activities that lead to aquatic habitat disruption and loss of biodiversity

61. Three Big Ideas (cont’d.)
We can sustain aquatic biodiversity
Establish protected sanctuaries, manage coastal development, reduce water pollution, and prevent overfishing

62. Tying It All Together: Sea Turtles and Sustainability
The sea turtle habitat is being destroyed
When oceans are left undisturbed, ecosystems tend to recover
We need to:
Reduce sediment inputs and excess nutrients
Value aquatic biodiversity