Current State of Our Orcas Highline Community College

Killer Whales- Orcas Orcinus orca Largest member of the dolphin family, Delphinidae Identifying traits –Tall dorsal fin –Saddle patch behind dorsal fin –White patches on sides, belly and behind eyes

Orca Biology Average Birth Weight: 395 lbs Average Adult Weight: 2.6 – 9 tons –Males are larger than females Lifespan: –Males ~40 years –Females >60 years Sexually mature ~13 years

Orca Natural History Found in all the world’s oceans Travel in pods from 3 to >150 members Feed on fish, squid and marine mammals

Transient vs. Resident Orcas TransientsResidents HabitatOffshoreNearshore FoodMarine Mammals Fish Pod Size3-5>20 VocalizationQuietVery Vocal

Resident Orcas Resident orcas live in coastal areas feeding mostly on fish Live in extended familial units called pods –Pods are matriarchal Northeast Pacific resident orcas are found from Puget Sound to Alaska –Puget Sound orcas are Southern Resident Orcas

Southern Resident Orcas Consists of three pods: J, K and L Summer in the area around the San Juan Islands feeding on salmon runs Winter on outer coast, but do not know where

Dead Orcas

State of Southern Resident Orcas Almost 20% orcas died between 1995 and Reproductive females have not produced young in ten years. Only four adult males in the entire community of 80 whales.

Puget Sound Orcas and PCBs Highest levels of PCBs in blubber of any marine mammal in the world –Average almost 150 ppm –<10 ppm PCB is known to cause immune problems in seals Dead female transient orca on Dungeness Spit in May 2002 –1000 ppm PCB –12ppm- EPA’s standard for marine sediments

Polychlorinated Biphenyls (PCBs) Cl

PCBs Highly stable oily fluids and solids –Transformers, pesticides, etc Fat soluble –Reside in fatty tissue Block hormone activity –Destroy normal immune function –Cause liver cancer, pituitary tumors, leukemia, and lymphoma Banned in U.S. since 1977

Ecosystem Review Ecosystem –Organisms interacting with environment and each other through a food chain Food Chain –Biomass moves from one organism to another as each eats a lower member and, in turn, is eaten by a higher member

Generalized Ecological Pyramid 2° Consumers 3° Cons g Biomass 100 g 10 g 1 g Primary Producers Primary Consumers

Idealized Puget Sound Ecological Pyramid 1000 g 100 g 10 g 1 g Phytoplankton Zooplankton Salmon Orcas

Pollutants Pollutant –Adversely affects the health, survival, or activities of living organisms –Persistent Organic Pollutant POP Stable, Long Lasting Includes DDT and PCBs

Factors Influencing Impact of Pollutants Solubility –Water soluble pollutants Move easily through environment –Fat soluble pollutants Need a carrier Long-lasting in body’s fatty tissue Persistence –More stable –Longer to break down –More harm it can do

Pollutants in the Food Chain Bioaccumulation –Cells increase the concentrations of molecules relative to the environment Biomagnification –Concentration of pollutants increases as they move up the ecological pyramid –Only 10% of biomass, but most of the pollutant is transferred

DDT in a Long Island Estuary (from Woodwell, Wurster and Isaccson, 1967) Trophic levelOrganismDDT in wet weight of whole organism Primary Producer Green Alga0.08 ppm Primary Consumer Mud Snail0.26 ppm Secondary Consumer Summer Flounder 1.28 ppm Tertiary Consumer Ring-billed Gull 75.5 ppm (1000x initial concentration)

Idealized Puget Sound Pyramid With PCBs 1000 g 100 g 10 g 1g Phytoplankton Zooplankton Salmon Orcas 1 g Trophic Level%PCB Phytoplankton0.1% Zooplankton1% Salmon10% Orcas100%

The ‘Double Whammy’ In blubber, PCBs are not very harmful. Low salmon runs force orcas to metabolize more blubber to survive. The blubber releases PCBs into the blood, destroying the immune system. Therefore, starvation increases the lethality of the pollutant.

Sources of Pollutants in the Environment Point Source –Specific location of concentrated pollutants Factory waste Sewage Nonpoint Source –Scattered or diffuse sources of pollutants Golf courses Agriculture