II. Orca Biologya. Birth Weight: 395 lbsb. Adult Weight: 2.6-9 tonsc. Males are larger than femalesi. Adult males also have a very tall, straight dorsal find. Lifespani. Males live to around 40 yearsii. Females live to over 60 yearsIII. Orca Natural HistoryVII. Ecosystem ReviewIX. Pollutants in EcosystemsCase Study: Puget Sound OrcasI. Killer Whales: Orcasa. Orcinus orcab. Largest member of the dolphin family (Delphinidae)c. Identifying traitsi. Tall dorsal finii. Saddle patch behind dorsal finiii. White patches on sides, belly and behind eyes II. Orca Biologya. Birth Weight: 395 lbs b. Adult Weight: 2.6-9 tonsc. Males are larger than femalesi. Adult males also have a very tall, straight dorsal find. Lifespani. Males live to around 40 yearsii. Females live to over 60 yearsIII. Orca Natural Historya. Distributioni. Orcas are found in all seas, including the Arctic and the tropicsb. Orcas travel in pods of 3 to >150 individualsc. Orca foodi. Fishii. Squidiii. Marine Mammalsd. Transient vs. Resident Orcasi. There are two major subspecies of orca, transients and residentsii. Transients live offshore, while residents live nearshoreiii. Transients feed mostly on marine mammals, while residents feed mostly on fishiv. Transients live in pods of 3-5 individuals, while residents live in pods of >20 individualsv. Transients tend to be very quiet, while residents make a lot of vocalizationse. Resident Orcasi. Resident orcas live in extended familial units called pods1. Pods are matriarchal in structure with the oldest female as the grandmother of the other orcasii. Northeast Pacific resident orcas are found in coastal waters from Puget Sound to Alaska1. Puget Sound resident orcas are the southern resident orcasa. Three pods: J,K and Lb. Summer around the San Juan Islands feeding on salmonc. Winter on the outer coast, though no one knows exactly whereIV. State of the Southern Resident Orcasa. 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.V. Southern Resident Orcas and PCBsa. 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 PCBVI. What are PCBsa. 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 excapedinto 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.VII. Ecosystem Reviewa. 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 chain1. 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.a. Marine Example: Kelp (primary producer) is eaten by sea urchins (primary consumer) that are eaten bysea 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 trophiclevel.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 level2. 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.VIII. Idealized Puget Sound Ecological Pyramida. 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.IX. Pollutants in Ecosystemsc. 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 DDTd. 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 sites1. 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