Ch 13 Sustaining Aquatic Biodiversity

1. Ch 13Sustaining Aquatic Biodiversity

2. Overview of Aquatic Biodiversity • World oceans cover 71% of the planet’s surface • 63% of known fish species exist in marine systems • 37% live in freshwater systems • Humans have only explored 5% of the earth’s global ocean • Ecological and economical benefits could result from further scientific study of poorly understood marine and freshwater systems. • Life As We Know It- 9min

3. Overview of Aquatic Biodiversity • 2003 – Pew Commission found U.S. coastal waters were in trouble and laws protecting them needed reforming • Commissions recommendations: • Double the federal $ for ocean research • Base fisheries management on preserving aquatic ecosystems and habitats rather than catch limits • Set up a systems of marine reserves • The Magnuson-Stevens Act- passed in 2007 which mandates annual catch limits and accountability measures and calls for international cooperation.

4. Overview of Aquatic Biodiversity • Coral reefs, estuaries, and the ocean bottom contain the greatest marine biodiversity • Greater variety of producers, habitats, food sources and nurseries • Biodiversity is higher near coastlines than open ocean • Benthic (bottom) regions have greater biodiversity than surface regions • Lowest diversity is the middle region of the open ocean • 6% of our total protein and 20% of our animal protein comes from marine fish and shellfish—potentially renewable resource.

5. Human Impacts on Aquatic Biodiversity • Greatest threat is loss and degradation of habitats • 1/2 of world’s coastal wetlands lost during the last century • 25% of world’s coral reefs severely damaged, mostly by humans • 1/3 of world’s original mangrove forests have disappeared, mostly due to clearing for development • Bottom habitats are being degraded and destroyed by dredging and trawler boat activity

6. Factory encroaching on wetlands Bleached Brain Coral

7. Human Impacts on Aquatic Biodiversity • 3/4 of the world’s 200 commercially valuable fish are either overfished or fished to their estimated sustainable yield. • Overfishing leads to commercial extinction • Modern fishing methods could cause 80% depletion in only 10-15 years • Large fish in many commercially valuable species are becoming scarce • Study showed in the last 45 yrs the abundance of large open ocean fish like tuna and bottom-dwelling fish like cod have fallen 90%

9. Human Impacts on Aquatic Biodiversity • After large species are disrupted, the fishing industry works its way down the food chain to smaller fish disrupting the food chain further • One-third of the annual fish catch is thrown overboard dead or dying as bycatch (nontarget species)

10. Human Impacts on Aquatic Biodiversity • 1200 marine species have become extinct in the past several hundred years • Fish are more threatened with extinction by human activity than any other animal • 37% of the known freshwater fish in the U.S and 20% of the 10,000 freshwater fish in the world are threatened with extinction or are already extinct (UN Food and Agriculture Organization)

11. Blue (Prionace glauca) and Mako shark fins at a shark finning camp, Magdalena Bay, Baja California, Mexico.

12. Human Impacts on Aquatic Biodiversity • Deliberate or accidental introduction of nonnative species into coastal waterways, wetlands, and lakes cost the U.S. about $16 million per hour • Purple loosestrife was imported into the U.S. in the 1880’s as an ornamental plant. • Released in ballast water • Single plant can produce 2.5 million seeds/yr • Native plants cannot compete • State have begun to introduce a weevil species and a leaf-eating beetle. Will they become pests?

14. Protecting and Sustaining Marine Biodiversity • Protecting marine biodiversity is difficult because • Much of the damage in not visible • Resources of the ocean viewed as inexhaustible • Most of the world’s oceans lies outside of legal jurisdictions so it is subject to over exploitation --tragedy

15. A California Sea Lion entangled in a fishing net that is slowly killing it. Protecting and Sustaining Marine Biodiversity • Protecting marine biodiversity is the same as protecting terrestrial biodiversity; identifying and protecting threatened and endangered species and their habitats

16. Case Studies: Commercial Fishing and Sea Turtles Major commercial fishing methods. Modern methods enable increasing harvest of decreasing populations.

17. Protecting and Sustaining Marine Biodiversity • 3 of 8 major sea turtle species are endangered and the rest are threatened • Degradation of beach habitat where they lay eggs, legal and illegal taking of eggs • Increased use as a food, medical ingredient, jewelry, and leather • Unintentionally captured and drowned by commercial fisherman – as many as 40,000/yr • Turtle exclusion devices have saved 1000’s of turtles from shrimp trawlers.

18. Turtle ejected here Shrimp end up here

19. Case Study: Whaling • Commercial Whaling (Cetaceans) • Easy to kill because of their large size and need to come to surface to breathe • Mass slaughter increased with the use of radar and airplane to locate the whales • 1.5 million whales killed between 1925 and 1975 • 8 of 11 major species became commercially extinct and the blue whale to the point of biological extinction

21. Protecting and Sustaining Marine Biodiversity • The International Whaling Commission (IWC) was established in 1946 to regulate the whaling industry by setting annual quotas • Did not work • IWC quotas were based on inadequate data or ignored by whaling countries • IWC did not have power of enforcement • In 1970, The U.S. stopped all whaling and banned the import of all whale products • In 1986, the IWC has imposed a moratorium on whaling. Whales killed dropped from 42,480 in 1970 to 1,200 in 2004

22. Protecting and Sustaining Marine Biodiversity • Norway and Japan continue to hunt certain species and Iceland resumed hunting in 2002 • Japan, Norway, Iceland, Russia, and a number of small tropical islands are working towards overthrowing the IWC whaling ban • A traditional part of the economies and culture of some countries • Believe ban is based on emotion not updated scientific estimates of whale populations • Eskimos still allowed to whale

23. 0 5 10 15 20 25 30m 0 10 20 30 40 50 60 70 80 90 100ft Atlantic white-sided dolphin Common dolphin Harbor porpoise Killer whale Bottlenose dolphin Beluga whale False killer whale Cuvier's beaked whale Pilot whale Narwhal Pygmy sperm whale Sperm whale Baird's beaked whale Squid Odontocetes (Toothed Whales)

24. Protecting and Sustaining Marine Biodiversity • The UN Law of the Sea- • All coastal nations have sovereignty over the waters 12 miles offshore • Jurisdiction over their Exclusive Economic Zone, which stretches 200 miles offshore • The rest is high seas • Control over 36% of the ocean and 90% of the fish stock yet the oceans are still over fished • World Conservation Union (IUCN) since 1986, has helped develop a global system of Marine Protected Areas (MPAs) • Protected from all or most of human activities • 1,700 existing MPAs protect about 0.2% of ocean area

25. Protecting and Sustaining Marine Biodiversity • Marine Reserves - no take or fully protected MPAs. • No extraction or alteration of living or nonliving resources is allowed • Australia has the largest • Results?-- Fish populations double, fish sizes grow by one-third, fish reproduction triples, and species diversity grows by almost one-fourth in 2-4 years • Less than 0.01% of the world’s ocean and 50 square miles in U.S. are in marine reserves

26. Protecting and Sustaining Marine Biodiversity • Integrated coastal management is community-based efforts to develop and use coastal resources more sustainably • Develop workable, cost effective, adaptable solutions that preserve biodiversity and still meet economic and social needs • Zone areas to include fully protected marine reserves and other zones where different levels of human activities are permitted • 90 coastal counties in the U.S. are working to establish integrated coastal management zones with 20 of them fully implemented

28. Managing and Sustaining The World’s Marine Fisheries • World commercial fishing has been managed by maximum sustained yield (MSY) -the maximum number of fish that can be harvested from a fish stock without causing a population drop. • Hasn’t worked • Fish stock difficult to measure and based on unreliable and underreported catch • Populations of other target and other non-target fish species and marine organisms also affected • Quotas are difficult to enforce

29. Managing and Sustaining The World’s Marine Fisheries • **Optimum sustained yield (OSY) -takes into account interactions with other species to provide more room for error • Multi-species management takes into account the competitive and predator-prey relationships of a number of interacting species

30. Proposed Catch Share Policy • 2009 Obama stated his administration’s commitment to creating comprehensive protective measure for our national fisheries and other oceanic wildlife. • NOAA Catch Share Policy has been drafted • Uses several fishery management strategies to allocate portions of the fishery catch to individuals, cooperatives, communities, etc. • Rebuild and sustain fisheries • Must stop fishing when their quota is reached • Prevents “race for the fish”

31. Protecting, Sustaining, and Restoring Wetlands • Coastal and inland wetland are areas of tremendous aquatic biodiversity • Federal permits required to fill in 3 or more acres of wetlands • Cut average wetland loss by 80% between 1969 and 2002 • 8% of remaining wetland are under federal control • Mitigation banking allows destroying existing wetlands in exchange for creation of artificial wetlands in another area. • 50% of created wetlands fail or do not replace the ecological functions of the natural wetlands

33. Protecting, Sustaining, and Restoring Lakes and Rivers • Great Lakes are the world’s largest body of fresh water • They have been invaded by 162 nonnative species since 1920. Most have arrive in the bilge water of ships • Sea lampreys • Zebra mussels • Asian carp – to reach the lakes soon • Nonnative species are their greatest threat.

34. Protecting, Sustaining, and Restoring Lakes and Rivers • Rivers and streams provide important ecological and economic services • Can be disrupted by over fishing, pollution, dams, and water withdrawal for irrigation • Lakes much more vulnerable than rivers. Why?

35. Case Study: Columbia River • Columbia River • World’s largest hydroelectric power system • Irrigation for agricultural land • Water source for major municipal areas • Salmon blocked from migrating upstream to lay their eggs due to dams disrupting rivers • Salmon needs trees along the river to keep water cool enough for the eggs to survive and to keep silt from covering them

37. Solutions Rebuilding Salmon Populations Building upstream hatcheries Releasing juvenile salmon from hatcheries to underpopulated streams Releasing extra water from dams to wash juvenile salmon downstream Building fish ladders so adult salmon can bypass dams during upstream migration Using trucks and barges to transport salmon around dams Reducing silt runoff from logging roads above salmon spawning streams Banning dams from some stream areas

38. Protecting, Sustaining, and Restoring Lakes and Rivers • Salmon Ranching has taken the place of wild salmon spawning • Salmon eggs and young are raised in hatcheries and released into the wildcompetition • Reduces the genetic diversity of the wild salmon • Environmental stress after fish release

39. Human capture Fish change form Salmon processing plant Fish enter rivers and head for spawning areas To hatchery In the fall spawning salmon deposit eggs in gravel nests and die Modified Life Cycle Eggs are taken from adult females and fertilized with sperm “milked” from males Grow to maturity in Pacific Ocean in 1-2 years Fry hatch in the spring... Normal Life Cycle Eggs and young are cared for in the hatchery And grow in the stream for 1-2 years Grow to smolt and enter the ocean... Fingerlings are released into river Fingerlings migrate downstream

40. Protecting, Sustaining, and Restoring Lakes and Rivers • 1968, National Wild and Scenic Rivers Act- protects rivers and river segments with outstanding scenic, recreational, geological, wildlife, historical or cultural value • Wild rivers may not be widened, straightened, dammed, filled, or dredged. • Swimming, camping, nonmotorized boating, sport hunting, and fishing are permitted • Scenic rivers are not dammed, mostly undeveloped, accessible by road in some areas and of great scenic value • Recreational rivers are readily accessible by roads and have some development along their shores

41. Natural Capital Ecological Services of Rivers • Deliver nutrients to sea to help sustain coastal fisheries • Deposit silt that maintains details • Purify water • Renew and renourish wetlands • Provide habitats for wildlife