1. Sustaining Aquatic Biodiversity
Chapter 11

2. Core Case Study: A Biological Roller Coaster Ride in Lake Victoria
Loss of biodiversity and cichlids
Nile perch: deliberately introduced
Frequent algal blooms
Nutrient runoff
Spills of untreated sewage
Less algae-eating cichlids

3. Lake Victoria Is a Large Lake in East Africa

4. Natural Capital Degradation: The Nile Perch

5. 11-1 What Are the Major Threats to Aquatic Biodiversity?
Concept Aquatic species are threatened by habitat loss, invasive species, pollution, climate change, and overexploitation, all made worse by the growth of the human population.

6. We Have Much to Learn about Aquatic Biodiversity
Greatest marine biodiversity
Coral reefs
Estuaries
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

7. Human Activities Are Destroying and Degrading Aquatic Habitats
Habitat loss and degradation
Marine
Coastal
Ocean floor: effect of trawlers
Freshwater
Dams
Excessive water withdrawal

8. Natural Capital Degradation: Area of Ocean Bottom Before and After a Trawler

9. Invasive Species Are Degrading Aquatic Biodiversity
Threaten native species
Disrupt and degrade whole ecosystems
Three examples
Water hyacinth: Lake Victoria (East Africa)
Asian swamp eel: waterways of south Florida
Purple loosestrife: indigenous to Europe
Treating with natural predators—a weevil species and a leaf-eating beetle—Will it work?

10. Invasive Water Hyacinths

11. Science Focus: How Carp Have Muddied Some Waters
Lake Wingra, Wisconsin (U.S.): eutrophic
Contains invasive species
Purple loosestrife and the common carp
Dr. Richard Lathrop
Removed carp from an area of the lake
This area appeared to recover

12. Lake Wingra in Madison, Wisconsin (U.S.)

13. Population Growth and Pollution Can Reduce Aquatic Biodiversity
Nitrates and phosphates mainly from fertilizers enter water
Leads to eutrophication
Toxic pollutants from industrial and urban areas

14. Hawaiian Monk Seal

15. Climate Change Is a Growing Threat
Global warming: sea levels will rise and aquatic biodiversity is threatened
Coral reefs
Swamp some low-lying islands
Drown many highly productive coastal wetlands
New Orleans, Louisiana, and New York City

16. Science Focus: Protecting and Restoring Mangroves
Protect and restore mangroves
Reduce the impact of rising sea levels
Protect against tropical storms and tsunamis
Cheaper than building concrete sea walls
Mangrove forests in Indonesia

17. Overfishing and Extinction: Gone Fishing, Fish Gone
Marine and freshwater fish
Threatened with extinction by human activities more than any other group of species
Commercial extinction
Collapse of the cod fishery and its domino effect
Bycatch

18. Natural Capital Degradation: Collapse of the Cod Fishery Off the Canadian Coast

19. 900,000
800,000
700,000
600,000
500,000
Fish landings (tons)
400,000
1992
300,000
Figure 11.6
Natural capital degradation: this graph illustrates the collapse of the cod fishery in the northwest Atlantic off the Canadian coast. Beginning in the late 1950s, fishers used bottom trawlers to capture more of the stock, reflected in the sharp rise in this graph. This resulted in extreme overexploitation of the fishery, which began a steady fall throughout the 1970s, followed by a slight recovery in the 1980s and total collapse by 1992 when the site was closed to fishing. Canadian attempts to regulate fishing through a quota system had failed to stop the sharp decline. The fishery was reopened on a limited basis in 1998 but then closed indefinitely in (Data from Millennium Ecosystem Assessment)
200,000
100,000
1900
1920
1940
1960
1980
2000
Year
Fig. 11-6, p. 254

20. Case Study: Industrial Fish Harvesting Methods
Trawler fishing
Purse-seine fishing
Longlining
Drift-net fishing

21. Major Commercial Fishing Methods Used to Harvest Various Marine Species

22. Deep sea aquaculture cage Fish caught by gills
Fish farming in cage
Trawler fishing
Spotter airplane
Sonar
Purse-seine fishing
Drift-net fishing
Long line fishing
Figure 11.7
Major commercial fishing methods used to harvest various marine species. These methods have become so effective that many fish species have become commercially extinct.
Float
Buoy
lines with hooks
Deep sea aquaculture cage
Fish caught by gills
Fig. 11-7, p. 256

23. Deep sea aquaculture cage
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 11.7
Major commercial fishing methods used to harvest various marine species. These methods have become so effective that many fish species have become commercially extinct.
Deep sea aquaculture cage
Stepped Art
Fig. 11-7, p. 256

24. 11-2 How Can We Protect and Sustain Marine Biodiversity?
Concept We can help to sustain marine biodiversity by using laws and economic incentives to protect species, setting aside marine reserves to protect ecosystems, and using community-based integrated coastal management.

25. Legal Protection of Some Endangered and Threatened Marine Species
Why is it hard to protect marine 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. Case Study: Protecting Whales: A Success Story… So Far
Cetaceans: Toothed whales and baleen whales
1946: International Whaling Commission (IWC)
1970: U.S.
Stopped all commercial whaling
Banned all imports of whale products
1986: moratorium on commercial whaling
Pros
Cons

27. Examples of Cetaceans

28. Figure 11.8
Examples of cetaceans, which can be classified as either toothed whales or baleen whales.
Fig. 11-8a, p. 258

29. Toothed whales Sperm whale with squid Killer whale Narwhal
Figure 11.8
Examples of cetaceans, which can be classified as either toothed whales or baleen whales.
Bottlenose dolphin 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30
Meters
Fig. 11-8a, p. 258

30. Figure 11.8
Examples of cetaceans, which can be classified as either toothed whales or baleen whales.
Fig. 11-8b, p. 258

31. Baleen whales Blue whale Fin whale Bowhead whale Right whale Sei whale
Figure 11.8
Examples of cetaceans, which can be classified as either toothed whales or baleen whales.
Humpback whale
Gray whale
Minke whale 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30
Meters
Fig. 11-8b, p. 258

32. Baleen whales Blue whale Fin whale Bowhead whale Right whale Sei whale
Toothed whales
Sperm whale with squid
Killer whale
Narwhal
Bottlenose dolphin 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30
Meters
Baleen whales
Blue whale
Fin whale
Bowhead whale
Right whale
Sei whale
Humpback whale
Gray whale
Minke whale 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30
Meters
Figure 11.8
Examples of cetaceans, which can be classified as either toothed whales or baleen whales.
Stepped Art
Fig. 11-8a, p. 258

33. Norwegian Whalers Harpooning a Sperm Whale

34. Economic Incentives Can Be Used to Sustain Aquatic Biodiversity
Tourism
Economic rewards
Reconciliation ecology

35. Case Study: Holding Out Hope for Marine Turtles
Carl Safina, Voyage of the Turtle
Studies of the leatherback turtle
Threats to the leatherbacks
Trawlers
Pollution
Climate change
Communities protecting the turtles

36. An Endangered Leatherback Turtle is Entangled in a Fishing Net

37. Individuals Matter: Creating an Artificial Coral Reef in Israel
Reuven Yosef, Red Sea Star Restaurant
Coral reef restoration
Reconciliation ecology
Treatment of broken coral with antibiotics

38. Marine Sanctuaries Protect Ecosystems and Species
Offshore fishing
Exclusive economic zones
High seas
Law of the Sea Treaty
Marine Protected Areas (MPAs)

39. Establishing a Global Network of Marine Reserves: An Ecosystem Approach (1)
Closed to
Commercial fishing
Dredging
Mining and waste disposal
Core zone
No human activity allowed
Less harmful activities allowed
E.g., recreational boating and shipping

40. Establishing a Global Network of Marine Reserves: An Ecosystem Approach (2)
Fully protected marine reserves work fast
Fish populations double
Fish size grows
Reproduction triples
Species diversity increase by almost one-fourth

41. Protecting Marine Biodiversity: Individuals and Communities Together
Integrated Coastal Management
Community-based group to prevent further degradation of the ocean

42. An Atoll of Australia’s Great Barrier Reef

43. Video: Humpback whales

44. Video: Loggerhead turtles

45. 11-3 How Should We Manage and Sustain Marine Fisheries?
Concept Sustaining marine fisheries will require improved monitoring of fish populations, cooperative fisheries management among communities and nations, reduction of fishing subsidies, and careful consumer choices in seafood markets.

46. Estimating and Monitoring Fishery Populations Is the First Step
Maximum sustained yield (MSY): traditional approach
Optimum sustained yield (OSY)
Multispecies management
Large marine systems: using large complex computer models
Precautionary principle

47. Some Communities Cooperate to Regulate Fish Harvests
Community management of the fisheries
Comanagement of the fisheries with the government

48. Government Subsidies Can Encourage Overfishing
2007: World Trade Organization, U.S.
Proposed a ban on fishing subsidies
Reduce illegal fishing on the high seas and in coastal waters
Close ports and markets to such fishers
Check authenticity of ship flags
Prosecution of offenders

49. Some Countries Use the Marketplace to Control Overfishing
Individual transfer rights (ITRs)
Control access to fisheries
New Zealand and Iceland
Difficult to enforce
Problems with the ITR approach

50. Consumer Choices Can Help to Sustain Fisheries and Aquatic Biodiversity
1997: Marine Stewardship Council (MSC), London
Supports sustainable fishing
Certifies sustainably produced seafood
Manage global fisheries more sustainably
Individuals
Organizations
Governments

51. Solutions: Managing Fisheries

52. SOLUTIONS Managing Fisheries Fishery Regulations Bycatch
Set catch limits well below the maximum sustainable yield
Use wide-meshed nets to allow escape of smaller fish
Improve monitoring and enforcement of regulations
Use net escape devices for seabirds and sea turtles
Economic Approaches
Ban throwing edible and marketable fish back into the sea
Sharply reduce or eliminate fishing subsidies
Aquaculture
Charge fees for harvesting fish and shellfish from publicly owned offshore waters
Restrict coastal locations for fish farms
Protect Areas
Control pollution more strictly
Depend more on herbivorous fish species
Certify sustainable fisheries
Figure 11.12
Ways to manage fisheries more sustainably and protect marine biodiversity and ecosystem services. Question: Which four of these solutions do you think are the most important? Why?
Establish no-fishing areas
Nonnative Invasions
Establish more marine protected areas
Kill organisms in ship ballast water
Rely more on integrated coastal management
Filter organisms from ship ballast water
Consumer Information
Label sustainably harvested fish
Dump ballast water far at sea and replace with deep- sea water
Publicize overfished and threatened species
Fig , p. 265

53. 11-4 How Should We Protect and Sustain Wetlands?
Concept To maintain the ecological and economic services of wetlands, we must maximize preservation of remaining wetlands and restoration of degraded and destroyed wetlands.

54. Coastal and Inland Wetlands Are Disappearing around the World
Highly productive wetlands
Provide natural flood and erosion control
Maintain high water quality; natural filters
Effect of rising sea levels

55. We Can Preserve and Restore Wetlands
Laws for protection
Mitigation banking
Ecologists argue this as a last resort

56. Natural Capital Restoration: Wetland Restoration in Canada

57. Individuals Matter: Restoring a Wetland
Jim Callender: 1982
Scientific knowledge + hard work =
a restored wetland in California, U.S.
Marsh used again by migratory fowl

58. Case Study: Can We Restore the Florida Everglades? (1)
“River of Grass”: south Florida, U.S.
Since 1948: damaged
Drained
Diverted
Paved over
Nutrient pollution from agriculture
Invasive plant species
1947: Everglades National Park unsuccessful protection project

59. Case Study: Can We Restore the Florida Everglades? (2)
1970s: political haggling
1990: Comprehensive Everglades Restoration Plan (CERP)
Restore the curving flow of most of the Kissimmee River
Remove canals and levees in strategic locations
Flood 240 sq. km farmland to create artificial marshes
Goal?

60. Case Study: Can We Restore the Florida Everglades? (3)
Comprehensive Everglades Restoration Plan (CERP) cont…
Create reservoirs and underground water storage areas
Build new canals, reservoirs and efficient pumping systems
Why isn’t this plan working?

61. The World’s Largest Restoration Project

62. 11-5 How Can Protect and Sustain Freshwater Lakes, Rivers, and Fisheries?
Concept Freshwater ecosystems are strongly affected by human activities on adjacent lands, and protecting these ecosystems must include protection of their watersheds.

63. Freshwater Ecosystems Are under Major Threats
Think: HIPPCO

64. 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
Good and bad
Quagga mussel
Asian carp

65. Zebra Mussels Attached to a Water Current Meter in Lake Michigan, U.S.

66. Managing River Basins Is Complex and Controversial
Columbia River: U.S. and Canada
Dam system
Pros and cons
Snake River: Washington state, U.S.
Hydroelectric dams

67. Natural Capital: Ecological Services of Rivers

68. We Can Protect Freshwater Ecosystems by Protecting Watersheds
Freshwater ecosystems protected through
Laws
Economic incentives
Restoration efforts
Wild rivers and scenic rivers
Sustainable management of freshwater fishes

69. Video: Salmon swimming upstream

70. 11-6 What Are the Priorities for Sustained Biodiversity, Ecosystem Services?
Concept Sustaining the world’s biodiversity and ecosystem services will require mapping terrestrial and aquatic biodiversity, maximizing protection of undeveloped terrestrial and aquatic areas, and carrying out ecological restoration projects worldwide.

71. We Need to Set Priorities for Protecting Biodiversity, Ecosystem Services
2002: Edward O. Wilson
Complete the mapping of the world’s terrestrial and aquatic biodiversity
Keep old-growth forests intact; cease their logging
Identify and preserve hotspots and deteriorating ecosystem services that threaten life
Ecological restoration projects
Make conservation financially rewarding