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Sustaining Aquatic Biodiversity. G. Tyler Miller’s Living in the Environment 13 th Edition Chapter 24. Key Concepts. Economic and ecological importance. Effects of human activities. Protecting and sustaining aquatic diversity. Protecting and sustaining fisheries. - PowerPoint PPT Presentation
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Sustaining Aquatic Biodiversity
G. Tyler Miller’sLiving in the Environment
13th Edition
Chapter 24
Key Concepts
Economic and ecological importance
Effects of human activities
Protecting and sustaining aquatic diversity
Protecting and sustaining fisheries
Protecting and restoring wetlands
Case Study: A Biological Roller Coaster Ride in Lake Victoria
• Lake Victoria has lost its endemic fish species to large introduced predatory fish.
A Biological Roller Coaster Ride in Lake Victoria
Reasons for Lake Victoria’s loss of biodiversity:• Introduction of Nile perch.• Loss of native cichlid species• Lake experienced algal blooms from
nutrient runoff.• Invasion of water hyacinth has blocked
sunlight and deprived oxygen.• Nile perch is in decline because it has
eaten its own food supply.
AQUATIC BIODIVERSITY• We know fairly little about the biodiversity of the world’s marine and freshwater systems.
• The world’s marine and freshwater systems provide important ecological and economic services.
The Importance of Aquatic Biodiversity
• The most biologically diverse habitats include:– Coral reefs– Estuaries– Deep ocean floor– Highest near the
coast– 25,000 known
fish species
The Importance of Aquatic Biodiversity:
Ecological and Economic • Food Items
– 6% of total protein; 16% of animal protein
• Many Chemicals– Cosmetics
• from seaweed– Medicines and Drugs
• Antibiotics and anticancer drug, adhesives, bone reconstructive materials
• seaweed, sponges, mollusks, coral barnacles, and other fish
APES Bell Ringer 11/28/2012
• What are 4 human impacts on aquatic biodiversity?
Human Impacts on Aquatic Biodiversity
• Species loss and endangerment• Marine habitat loss and
degradation• Freshwater habitat loss and
degradation• Overfishing• Nonnative species• Pollution and global warming
Species Loss and Endangerment
• Overfishing• Habitat destruction• Pollution• Freshwater species at greater risk
– Mussels, crayfish, amphibians, fish
Marine Habitat Loss and Degradation
• 53% of coastal wetlands in US have disappeared– Agriculture– Coastal development
• 58% of world’s coral reefs are threatened– Coastal development– Pollution– Warmer ocean temperatures
• Two-thirds of US estuaries are at risk from pollution
• 35% of world’s mangroves have disappeared
Freshwater Habitat Loss and Degradation
• The world has lost more than half of its inland wetlands– Agricultural and urban development
• 60% of the world’s larger rivers are fragmented by dams, diversions, and canals
• Flood control levees and dikes– Alter and destroy aquatic habitats– Disconnect rivers from their floodplains– Eliminate wetlands and backwaters
(spawning areas)
Overfishing
• 75% of the world’s 200 commercially valuable marine fish species are overfished
• Overfishing leads to commercial extinction
• Depletions and extinction of species unintentionally caught as bycatch
Non-native Species
• Deliberate or accidental introduction into coastal waters, lakes and wetlands– purple loosestrife– Asian swamp eel– zebra mussle
• Displace or cause extinction of native species– 68% of fish extinctions
Pollution and Global Warming
• Major pollution threats– Oil– Acid deposition– Plant nutrients– Toxic chemicals– Coastal
development– Sediment and soil
erosion
• Global warming could– alter migration and
feeding patterns– increase ocean
temperature– raise sea levels
• 44% comes from runoff from developed coastal areas
PROTECTING AND SUSTAINING MARINE BIODIVERSITY
• Six of the world’s seven major turtle species are threatened or endangered because o human activities.
Figure 12-4
Protect endangered and threatened species
• Example: Sea turtle– Turtle extrusion devices (TEDs)
LoggerheadOlive ridley
Leatherback
Hawksbill
Green turtleKemp's Ridley
Black turtle
Australian flatback
Shrimp trawler
Area enlarged right
Turtle Extrusion Device
Case Study: The Florida Manatee and Water Hyacinths
• Manatee can eat unwanted Water Hyacinths.
• Endangered due to:– Habitat loss.– Entanglement from
fishing lines and nets.– Hit by speed boats.– Stress from cold.– Low reproductive rate
Case Study: Commercial Whaling
• After many of the world’s whale species were over-harvested, commercial whaling was banned in 1960, but the ban may be overturned.
Commercial Whaling
• Despite ban, Japan, Norway, and Iceland kill about 1,300 whales of certain species for “scientific purposes”.– Although meat is still
sold commercially.
Key Concepts
Economic and ecological importance
Effects of human activities
Protecting and sustaining aquatic diversity
Protecting and sustaining fisheries
Protecting and restoring wetlands
Protecting and Sustaining Marine Biodiversity
• Identifying and protecting endangered and threatened species– Sea turtles
• Turtle extrusion devices (TEDs)• National and International laws and
treaties• CITES - Convention on International Trade
and Endangered Species• Global Treaty on Migratory Species• US Marine Mammal Protection Act• US Endangered Species Act• US Whale Conservation and Protection Act• International Convention on Biological
Diversity
Protecting and Sustaining Marine Biodiversity
• Establish marine protected areas– Coastal nations have sovereignty over
waters and seabeds up to 12 miles offshore
– Jurisdiction over their Exclusive Economic Zone extends 200 miles offshore
• Integrated coastal management– community based attempt to develop
and use coastal resources sustainably
Protecting and Sustaining Marine Biodiversity
• Regulating and preventing ocean pollution
• Sustaining management of marine fisheries
Managing and Sustaining the World’s Marine Fisheries
• Fishery regulation– Set, monitor, and enforce fishery catch limits below estimated MSY (maximum sustained yield)– Divide up fishing quotas– Require selective gear– Improve monitoring and enforcement
• Economic approached– Reduce or eliminate subsidies– Impose fees for harvesting fish and shellfish from public managed offshore waters– Certify sustainable fisheries
Managing and Sustaining the World’s Marine Fisheries
• Bycatch reduction– Wider mesh fish nets– Extrusion devices– Observers on boats– Multiple species licensing– Laws prohibiting throwing edible and marketable fish back to sea
Managing and Sustaining the World’s Marine Fisheries
• Protected areas– Establish no-fishing marine areas– Protect marine habitats that are in good condition and disregard potentially hopeless cases– Strengthen commitment to marine biodiversity protection
• Non-native invasions– Kill organisms in ship ballast water– Develop filters and traps– Require ships to dump ballast water beyond 200 mile limit
Managing and Sustaining the World’s Marine Fisheries
• Consumer information– Use labeling to identify fish that have been harvested sustainably
• Aquaculture– Restrict location of fish farms to reduce loss of mangrove forests– Enact and enforce stricter pollution regulations– Increase productions of herbivorous aquaculture fish species
Protecting, Sustaining, and Restoring Wetlands
• Regulations– federal permit required
• Mitigation banking– allows destruction of existing wetlands if an equal area
of they same type of wetland is created or restored• Land use planning
– steer agriculture and mining away from wetlands• Wetland restoration
– often has limited success• Control of invasive species
– purple loosestrife
Restoring the Florida Everglades
• Natural flow of the Everglades has been diverted or disrupted.
• Farmers planted vast agricultural land to sugarcane and vegetables.
• Established Everglades National Park. Became the most endangered park.
• Massive plumbing and land development projects cut off water flow
Restoring the Florida Everglades
• 1990 began the world’s largest ecological restoration project.– restore he curving flow of
more than half of the Kissimmee River.
– remove 400 km of canals and levees
– create artificial marshes in previous farmland
– add land adjacent to Everglades National Park
– create network of artificial marshes
– create 18 large reservoirs– capture much of the water
flowing out to sea and return it to the Everglades
Protecting, Sustaining, and Restoring Wetlands
Protecting, Sustaining, and Restoring Lakes Pollution
Invasive species
Water levels
Cultural eutrophication
Zebra mussel
Protecting, Sustaining, and Restoring Rivers
Pollution Disruption of
water flow Loss of
biodiversity Invasive
species
Protecting, Sustaining, and Restoring Rivers Disruption of water flow
119 dams, 19 hydroelectric dams Salmon population
dropped 94%
Salmon Restoration Project upstream hatcheries fish ladders transport juveniles
around dams turning off turbines
PROTECTING, SUSTAINING, AND RESTORING LAKES AND RIVERS• We can help sustain freshwater fisheries
by building and protecting populations of desirable species, preventing over-fishing, and decreasing populations of less desirable species.
• A federal law helps protect a tiny fraction of U.S. wild and scenic rivers from dams and other forms of development.– National Wild and Scenic Rivers Act
(1968).