Sustaining Aquatic BiodiversitySustaining Aquatic Biodiversity

Unit FourChapter 13APES Mrs. Dow

A Biological Rollercoaster Ride in A Biological Rollercoaster Ride in Lake VictoriaLake Victoria

AFRICA

ZAIRE

BURUNDI

TANZANIA

KENYA

ETHIOPIASUDAN

LAKEVICTORIA

East Africa World’s 2nd largest freshwater lake Until the late 1980 it had more than 500 endemic

species of fish 80% cichlids- small algae eating fish Since 1980 some 200 cichlid species have become

extinct Nile perch was deliberately introduced during the

50’s & 60’s to stimulate fishing industry Frequent alga blooms Water hyacinth invaded and rapidly took over Nile perch is now being overfished

Aquatic Biodiversity 13.1Aquatic Biodiversity 13.1

Oceans cover 71% of Earth surface Only explored 5% of the earth’s global oceans

U.S. coastal waters in trouble Pass National Ocean Policy Act

– Protects, sustains, restores the living oceans– Double federal budget for ocean research – Fisheries management– Marine reserves for breeding

Kelp

Hogfish

Cobia

Pacific sailfishCarrageen

Yellow jack

Batfish

MorayRed snapper Red algae

Striped drum AngelfishBladder kelp

Sea lettuce Orange roughyChinook salmon

DevilfishGreat barracuda

Laminaria

Porcupine fish

Sockeye salmonGrouper

Dulse Chilean sea bass

Marine Marine BiodiversityBiodiversity

Bulrush

BluegillWhite bass

Brook trout White waterlily

Water lettuce

Rainbow trout

Muskellunge

Bowfish Water hyacinth

Rainbow darter

Bladderwort

Black crappieWhite sturgeon 

Yellow perch

Largemouth black bass

Walleyed pike

American smelt

EelgrassLongnose garDuckweed

Common piranha

Carp

African lungfish

Egyptian white lotus

Channel catfish

Velvet cichlid

Freshwater Freshwater BiodiversityBiodiversity

Marine (ocean) biodiversityMarine (ocean) biodiversity

Coral reefs & deep-sea (greatest)Greater near coasts (habitats, producers)Lowest diversity in middle (no habitat)

Source of proteinSeaweed (cosmetics, pharmaceuticals)Antibiotics/anticancer

Human impacts 13.2Human impacts 13.2

Greatest threat (loss & degradation of habitat)

½ worlds coasts lost in last centuryCoral reefs severely damaged>33% mangrove swamps goneDredging destroying habitats¾ marine species over fished

OverfishingOverfishing

Leads to commercial extinction– Industrialized– 90% loss of large, open sea fish– Faster-growing varieties @ top of trophic level

taken– 1/3 fish caught are bycatch

Present

Not present

No data

Purple loosestrifePurple loosestrife

Freshwater animals are disappearing 5x faster than land animals

Seahorse used in Chinese medicine

Nonnative threat– Displace native; arrive in ship ballast– Asian eel- invaded waterways of South FL– Purple loosestrife imported as a ornamnetal plant

Protecting Marine Environments 13.3Protecting Marine Environments 13.3

Difficult– Coastal development; inputs of sediment, waste– Hard to visualize damage– False sense that large size of ocean prevents

damage– Deemed “tragedy of commons”

Whale

Seal

Turtle

Sea lion

Bowhead whale

HumpbackwhaleNorthern right

whale

Fin whaleHawksbillturtle

Hawaiianmonk seal

Hawksbillturtle

Greenturtle Leatherback

turtle

Greenturtle

Humpbackwhale

Fin whale

Humpbackwhale

Hawksbillturtle

Greenturtle

HawksbillturtleKemp's

ridley turtle

Leatherbackturtle

Olive ridleyturtle

Fin whale

Humpbackwhale

Bowhead whale

Bowhead whale

Northern rightwhale Mediterranean

monk seal

Leatherbackturtle

Hawksbillturtle

Oliveridleyturtle

Leatherbackturtle

Humpbackwhale

Fin whale

Leatherbackturtle

Greenturtle

Oliveridleyturtle

Japanesesea lion

Bowhead whale

Hawksbillturtle

Saimaa seal

Loggerhead119 centimeters

Olive ridley76 centimeters

Leatherback188 centimeters

Hawksbill89 centimeters

Green turtle124 centimeters

Kemp's ridley 76 centimeters

Black turtle99 centimeters

Australian flatback

99 centimeters

Species of Sea TurtlesSpecies of Sea Turtles

To protect endangered marine species– Identify & protect endangered/threatened

species– Prevent pollution– Educate public– CITES of 1975- 1979 Global treaty on Migratory Species- U.S. Marine Mammal Protection Act of 1972- U.S. Endangered Species Act of 1973– U.S. Whale Conservation & Protection Act

(1976)– International Convention on Biological

Diversity (1995)

Atlanticwhite-sideddolphin

Harborporpoise

Commondolphin

Killerwhale

Belugawhale

Bottlenosedolphin

False killerwhale

Pilotwhale

Cuvier'sbeakedwhale

Pygmyspermwhale

Spermwhale

Narwhal

Squid

Baird'sbeakedwhale

Odontocetes (Toothed Whales)

0 5 10 15 20 25 30m

0 10 20 30 40 50 60 70 80 90 100ft

Humpback whale

Bowhead whale

Right whaleMinke whale

Blue whale

Feeding on krill

Fin whale

Sei whale

Gray whaleMysticetes (Baleen Whales)

WhalesWhales

Commercial whaling banned in 1970– Easy targets– 8 of 11 driven to commercial extinction– Alaska natives are exempt– Blue whale to edge of extinction

10,000 left; low birth rate

International Whaling Commission (1946) – Sets quota for harvesting

Nations have 12 miles off coast to harvestExclusive Economic Zone (EEZ)

– 200 miles from shore

90 marine reserves in world

Integrated coastal management – Find cost-effective was to preserve biodiversity

U.S. banned all whaling (1970)Japan, Norway, Iceland, Russia want ban

repelled

Managing & sustaining 13.4Managing & sustaining 13.4

Better way to project fish populations– Hard to measure– Based on unreliable catch figures– Quotas are hard to enforce

– Mediterranean Sea has limited management

Suggestions– Central gvt sets quotas– Individual transfer quotas (ITQs)

Assigned to each fisherman Limits bought, sold, leased

Wetlands 13.5Wetlands 13.5

Critical for aquatic biodiversity– Law permits fill or

dredges

Everglades National Park– 90% wading birds gone– Saltier & warmer (lack of water

flow)– Large algal blooms

( )

( )

GULF OFMEXICO

Naples

Fort Myers

FLORIDA

Florida Bay

EvergladesNational

Park

Key Largo

ATLANTIC OCEAN

Miami

FortLauderdale

WestPalmBeach

LakeOkeechobee

Unchannelized

Channelized

FLORIDA

Area ofdetail

Agricultural area

Treatment marsh

Water conservation area

Canal

miles

kilometers

0

0

20

20

40

40 60

60

KissimmeeRiver

Restoring the Florida EvergladesRestoring the Florida Everglades

U.S. Army Corp of Engineers– Restoring flow of Kissimmee River– Removing canals south of Lake Okeechobee– Allow farmland to become marshes– Create reservoirs, canals, pumping stations

Restoring lakes & rivers 13.6Restoring lakes & rivers 13.6

Great Lakes– 162 nonnative species– Sea lampreys (reduce sport fish)– Zebra mussels (displaced native mussels;

clogged pipes; fouled beaches)

Columbia River-North America’s 4th largest river

– Altered by 119 dams; withdrawal of water for ag Salmon need to return to spawning grounds Salmon provide food; fertilizer for trees Lack of trees makes water too warm 9 species of Salmon are endangered or threatened

Northwest Power Act (1980)– Provide power & restore salmon

Figure 13-13Figure 13-13Page 268Page 268

Fish change form

Fish enter riversand head forspawning areas

Grow to smoltand enter the ocean...

Grow to maturityin Pacific Oceanin 1-2 years

Eggs and young arecared for in the hatchery

Fry hatch in the spring...

Fingerlings migrate downstream

In the fall spawning salmondeposit eggs in gravel nests and die

NormalLifeCycle

Fingerlingsare released into river

And grow in the streamfor 1-2 years

Human capture

Salmonprocessingplant

Eggs are taken from adultfemales and fertilized withsperm “milked” from males

ModifiedLifeCycle

To hatchery

Sustainable management for Sustainable management for freshwaterfreshwaterRegulate fishing; # & size takenImprove habitats, breed genetically strong

fish

Wild and Scenic Rivers Act (1968) – Protect rivers