I II III IV Case Study Puget Sound Orcas Killer Whales Orcas a Orcinus orca b Largest member of the dolphin family Delphinidae c Identifying traits i Tall dorsal fin ii Saddle patch behind dorsal fin iii White patches on sides belly and behind eyes Orca Biology a Birth Weight 395 lbs b Adult Weight 2 6 9 tons c Males are larger than females i Adult males also have a very tall straight dorsal fin d Lifespan i Males live to around 40 years ii Females live to over 60 years Orca Natural History a Distribution i Orcas are found in all seas including the Arctic and the tropics b Orcas travel in pods of 3 to 150 individuals c Orca food i Fish ii Squid iii Marine Mammals d Transient vs Resident Orcas i There are two major subspecies of orca transients and residents ii Transients live offshore while residents live nearshore iii Transients feed mostly on marine mammals while residents feed mostly on fish iv Transients live in pods of 3 5 individuals while residents live in pods of 20 individuals v Transients tend to be very quiet while residents make a lot of vocalizations e Resident Orcas i Resident orcas live in extended familial units called pods 1 Pods are matriarchal in structure with the oldest female as the grandmother of the other orcas ii Northeast Pacific resident orcas are found in coastal waters from Puget Sound to Alaska 1 Puget Sound resident orcas are the southern resident orcas a Three pods J K and L b Summer around the San Juan Islands feeding on salmon c Winter on the outer coast though no one knows exactly where State of the Southern Resident Orcas V VI VII a Almost 20 of Southern resident orca community died between 1995 and 2000 b Many females who should be in their reproductive years have not produced viable young for ten years c Young males are dying rapidly and there are only four adult males in the entire community Southern Resident Orcas and PCBs a Southern resident orcas have on average the highest measured levels of PCBs of any marine mammal in the world almost 150 ppm i 10ppm PCB is known to cause immune problems in seals b PCBs build up over the years and are passed from mother to calf via her milk i A mother can pass on as much as 90 of PCBs to her offspring c A female transient orca was found dead on Dungeness Spit in May 2002 had 1000ppm PCB What are PCBs a Polychlorinated biphenyls PCBs A class of persistent organic pollutant POP Oily fluids that are very stable and resist degredation They have been used in transformers pesticides carbonless copy paper and small electrical parts i Manufactured in the U S from 1929 to 1977 peak production of PCBs in the United States occurred during the 1950 s and 1960 s ii Roughly one third of the world s total PCB production has excaped into the environment iii Products with PCBs leak then into the soil and water where the molecules rise into the atmosphere and are carried by the wind and redeposited all over the earth iv PCBs are fat soluble thus entering the food chain and residing in fatty tissues of all the organisms in the food chain 1 In rodent assays PCBs cause liver cancer pituitry tumors leukemia lymphoma and intestinal cancer 2 PCBs are classified as a probable human carcinogen v Production has been banned in the U S since 1977 Ecosystem Review a Ecosystem an array of organisms and the physical environment interacting through a one way flow of energy and cycling of material i Energy flows through ecosystems but matter is cycled ii Energy flows through the ecosystem via the food chain 1 Food Chain A succession of organisms in an ecological community that constitutes a continuation of food energy from one organism to another as each consumes a lower member and in turn is preyed upon by a higher member 1 Begins with primary producers which are consumed eaten by primary consumers secondary producers which are consumed by secondary consumers and so on VIII IX a Marine Example Kelp primary producer is eaten by sea urchins primary consumer that are eaten by sea otters secondary consumer b Ecological Pyramid The flow of energy through an ecosystem can be visualized as pyramid with each level representing a different trophic level and the size of that level is proportional to the biomass in that trophic level i Because not all of the biomass of the preceding trophic level is used in the next trophic level the higher trophic levels have less biomass 1 Ecological efficiency percentage of energy taken in as food by one trophic level and then passed on as food to the next trophic level 2 Ecological efficiency for most communities is about 10 a Ex 100 grams of kelp will sustain 10 grams of sea urchin which will sustain 1 gram of sea otter Idealized Puget Sound Ecological Pyramid a The resident orcas of Southern Puget Sound are the top predators of the Puget Sound food chain i Their preferred food is salmon whose numbers have been seriously declining over the last decade ii The salmon feed mostly on zooplankton in particular euphausiid krill which in turn feed on phytoplankton the primary producers of the marine ecosystem Pollutants in Ecosystems c Pollutant Any agent that adversely affects the health survival or activities of living organisms or that alters the environment in undesirable ways i Persistent Organic Pollutants POPs are synthetic organic compounds used in various products from electronics to automobiles that resist environmental degradation and have been found to adversely affect the environment 1 Include PCBs and DDT d How do pollutants enter the environment i Point Sources Specific locations of highly concentrated pollutant discharge such as factories power plants and sewage treatment plants 1 Example For decades GE dumped thousands of tons of PCBs into the Hudson River ii Nonpoint Sources Scattered diffuse sources of pollutants such as runoff from farm fields and construction sites 1 Example Golf courses utilize large amounts of fertilizer which can pollute the surrounding water e Factors influencing the movement of a pollutant through an ecosystem i Solubility of the Pollutant determines how where and when a pollutant will move through the environment 1 Water soluble pollutants move rapidly and widely through the environment because water is ubiquitous 2 Fat Soluble pollutants generally need a carrier to move through the environment and into and within the body a Once inside the body fat soluble pollutants penetrate readily into tissues and cells where they accumulate and are stored as lipid deposits that