Impact of Pollution on aquatic systems

1. Impact of Pollution on aquatic systems http://www.gdrc.org/oceans/marine-pollution.html

2. The Great Garbage Patch

3. North Pacific Gyre Subtropical Gyres

4. North Pacific Gyre Subtropical Gyres

5. North Pacific Gyre • Great Pacific Garbage Patch • Small plastic debris is concentrated in the center of ocean gyres • Currents push trash into the center of a gyre, where it remains.

6. North Pacific Gyre • Great Pacific Garbage Patch • In the pacific, this area of concentrated plastic may be twice the size of Texas • Contains 3.5 million tons of plastic garbage www.greatgarbagepatch.org

7. Most pieces of plastic are <10mm • Many pieces are microscopic • Can be ingested by animals • Block some sunlight

8. Effects of plastic on wildlife

9. Sources and Effects of Marine Pollutants

10. Nutrient Pollution Primary Source/Cause Effect • Runoff approximately 50% sewage, 50% from forestry, farming, and other land use. Also airborne nitrogen oxides from power plants, cars etc. • Feed algal blooms in coastal waters. Decomposing algae depletes water of oxygen, killing other marine life. Can spur algal blooms (red tides), releasing toxins that can kill fish and poison people.

11. Sediments Primary Source/Cause Effect • Erosion from mining, forestry, farming, and other land-use; coastal dredging • Cloud water; impede photosynthesis below surface waters. Clog gills of fish. Smother and bury coastal ecosystems. Carry toxins and excess nutrients.

12. Pathogens Primary Source/Cause Effect • Sewage, livestock. • Contaminate coastal swiming areas and seafood, spreading cholera, typhoid and other diseases.

13. Persistent Toxins (PCBs, Heavy metals, DDT etc.) Primary Source/Cause Effect • Industrial discharge; wastewater discharge from cities; pesticides from farms, forests, home use etc.; seepage from landfills. • poison or cause disease in coastal marine life, especially near major cities or industry. Contaminate seafood. Fat-soluble toxins that bio-accumulate in predators can cause disease and reproductive failure.

14. Oil Primary Source/Cause Effect • 46% from cars, heavy machinery, industry, other land-based sources; 32% from oil tanker operations and other shipping; 13% from accidents at sea; also offshore oil drilling and natural seepage. • Low level contamination can kill larvae and cause disease in marine life. Oil slicks kill marine life, especially in coastal habitats. Tar balls from coagulated oil litter beaches and coastal habitat. Oil pollution is down 60% from 1981.

15. Re-release ≠ Survival • During Exxon Valdez, • 878 otter carcasses recovered • 357 live otters rescued for rehab • 61 (17%) uncontaminated • 123 (35%) only lightly oiled • 197 otters re-released • Half of radio-tagged released otters were missing/confirmed dead within a year • “Of the thousands of sea otters that came into contact with the spilled oil, rehabilitation brought fewer than 150 through to the post-spill living population” Photo: Anchorage Daily News (Estes 1991; Estes 1998)

16. Post-release Survival • Long-term recovery rate for oiled guillemots is significantly lower than three different non-oiled controls • Mean life expectancy of rehabbed and released guillemots was 9.6 days Ecomare (Sharp 1996)

17. Post-release Breeding • For little penguins: • Egg-laying delayed for oiled birds • Hatching success not affected • Overall egg success significantly lower for oiled birds • Lower quality offspring for oiled birds for at least 2 yrs Photo: Australian Bureau of Meteorology (Giese et al. 2000b)

18. Post-release Survival NOTE* • Oiled little penguins have lower survival rates than non-oiled • 53% and 44% vs. 77% survival • Probability of survival (already low) decreased by 9% with each ¼ of the bird that is covered in oil Photo: Tanya Dropbear (Giese et al. 2000a)

19. Costs ofRehabilitation • During Exxon Valdez spill, millions of dollars were spent on rescuing and rehabilitating animals • $1.7 million spent on sea otters • $80,000 per released otter • $41 million spent to rescue and treat only 400 birds (Estes 1998; Sharp 1996)

20. Post-release Survival NOTE* • Increased disappearance rates for oiled pelicans • Control: 53% still accounted for 2 yrs later • Rehabbed pelicans: 9% still accounted for 2 yrs later • Rehabbed juveniles may survive slightly better than adults • Known mortality increased for rehabilitated pelicans Photo: National Geographic (Anderson et al. 1996)

21. Post-release Survival NOTE* • Rehabilitated guillemots traveled far less than control birds • Rehabilitated pelicans traveled significantly different amounts than control • 1990: less • 1991: much more (birds oiled later in season) (Anderson et al. 1996; Sharp 1996)

22. Post-release SurvivalNOTE* • Long-term recovery rate for oiled guillemots is significantly lower than three different non-oiled controls • Mean life expectancy of oiled, rehabbed guillemots: 107 days • Mean life expectancy of non-oiled guillemots: 485 days (Sharp 1996) Photo: Canada Dept of Fish and Game

23. Post-release BreedingNOTE* • Rehabbed pelicans did not breed or even consistently go to breeding colonies • Even brief Crude oil exposure reduces breeding success in shearwaters for at least two seasons US FWS (Anderson et al. 1996;Fry et al. 1986 in Anderson et al. 1996)

24. Low Danger of Extinction NOTE* • The argument: An oil spill could cause extinction of a population (e.g. California sea otters) • An Exxon Valdez-size spill in CA would have <5% chance of reducing otter populations to near-extinction levels Photo: Fox (Estes 1998)

25. Summary NOTE* • It may be difficult to determine if a wild animal has actually been exposed to oil • Rehabilitation can be stressful • Survival rates for rehabilitated oiled animals are often lower than un-oiled counterparts • Decreased breeding success • Non-normal post-release movements • Rehabilitation is extremely expensive Photo: Charlie Riedel /AP

26. Summary NOTE * cont. • If oiled animals must be removed from the environment, but rehabilitation is very expensive but not very effective at improving survival, isn’t the most humane solution to euthanize any animal that is more than lightly oiled? Photo: USCG

27. Plastics Primary Source/Cause Effect • Fishing nets; cargo and cruise ships; beach litter; wastes from plastics industry and landfills. • Discard fishing gear continues to catch fish. Other plastic debris entangles marine life or is mistaken for food. Plastics litter beaches and coasts and may persist for 200 to 400 years.

28. Radioactive substances Primary Source/Cause Effect • Discarded nuclear submarine and military waste; atmospheric fallout; also industrial wastes. • Japan • Hot spots of radio activity. Can enter food chain and cause disease in marine life. Concentrate in top predators and shellfish, which are eaten by people.

29. Thermal Primary Source/Cause Effect • Cooling water from power plants and industrial sites • Kill off corals and other temperature sensitive sedentary species. Displace other marine life.

30. Noise Primary Source/Cause Effect • Supertankers, other large vessels and machinery • Can be heard thousands of kilometers away under water. May stress and disrupt marine life.

31. Pollution Highlight • Methylmercury

32. Major Pollutants: Mercury • Methylmercury • Causes neurological problems • Disruption of sensory system, blindness • Lack of coordination • Slurred speech • Impaired growth • Reproductive failure • How do you get exposed?

33. Major Pollutants: Mercury • Methylmercury • Causes neurological problems • Disruption of sensory system, blindness • Lack of coordination • Slurred speech • Impaired growth • Reproductive failure • How do you get exposed? • Consumption of seafood Photos: Wikipedia

34. Methylmercury Exposure

35. Methylmercury • Mercury occurs naturally in the environment and can also be released into the air through industrial pollution. • Mercury falls from the air and can accumulate in streams and oceans and is turned into methylmercury in the water

36. Methylmercury • People who regularly consume a lot of fish will have larger levels of toxic chemicals in their bodies than those who only eat fish occasionally • studies have suggested that toxic chemicals can lead to reproductive problems, cancer and neurological disorders

37. http://www.nytimes.com/2009/08/20/science/earth/20brfs-MERCURYFOUND_BRF.html?_r=1http://www.nytimes.com/2009/08/20/science/earth/20brfs-MERCURYFOUND_BRF.html?_r=1

38. Mercury in Children • Once in the human body, mercury acts as a neurotoxin, interfering with the brain and nervous system. • Prenatal and infant mercury exposure can cause mental retardation, cerebral palsy, deafness and blindness. Even in low doses, mercury may affect a child's development, delaying walking and talking, shortening attention span and causing learning disabilities.

39. Mercury poisoning in infants

40. Scary….. • A July 2005 report from the federal Centers for Disease Control and Prevention (CDC) concluded that one in 17 women of childbearing age have mercury in their blood above 5.8 micrograms per liter of blood -- a level that could pose a risk to a developing fetus

41. Mercury in Adults • affect fertility and blood pressure regulation and can cause memory loss, tremors, vision loss and numbness of the fingers and toes

42. Table 1. Fish and Shellfish With Highest Levels of Mercury http://www.fda.gov/food/foodsafety/product-specificinformation/seafood/foodbornepathogenscontaminants/methylmercury/ucm115644.htm

43. Table 2. Fish and Shellfish With Lower Levels of Mercury†

45. Water Pollution • The effects of water pollution can range from aquatic deformities to contaminated fish to "dead" lakes. • Heavy metals such as mercury and lead, and human-made organic chemicals such as pesticides, bioaccumulate as they move up the food chain • results in tumors and death for predatory animals, such as lake trout, herring, gulls, and even humans

46. Pollutants • Toxic pollutants can also alter the genetic makeup of an organism, resulting in either death or extreme deformities • Studies have found cormorants suffering from cross-billed syndrome at rates 42 percent times the natural occurrence • terns exhibit birth defects from dioxin, PCBs and furan exposure at 31 times the normal levels

47. Texas A&M Reserach • Effects of pollution on fish species diversity in Galveston Bay, Texas. Bechtel, T.J.; Copeland, B.J. 1971 • We’ve been looking at this in Texas for over 40 years, STILL no long-term solutions…..