Current State of Our Orcas

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Current State of Our Orcas
Highline Community College
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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

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Orca Biology

• Average Birth Weight 395 lbs
• Average Adult Weight 2.6 9 tons
• Males are larger than females
• Lifespan
• Males 40 years
• Females gt60 years
• Sexually mature 13 years

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Orca Natural History

• Found in all the worlds oceans
• Travel in pods from 3 to gt150 members
• Feed on fish, squid and marine mammals

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Transient vs. Resident Orcas
Transients Residents
Habitat Offshore Nearshore
Food Marine Mammals Fish
Pod Size 3-5 gt20
Vocalization Quiet Very Vocal
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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

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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

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Dead Orcas
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State of Southern Resident Orcas

• Almost 20 orcas died between 1995 and 2000.
• Reproductive females have not produced young in
  ten years.
• Only four adult males in the entire community of
  80 whales.

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Puget Sound Orcas and PCBs

• Highest levels of PCBs in blubber of any marine
  mammal in the world
• Average almost 150 ppm
• lt10 ppm PCB is known to cause immune problems in
  seals
• Dead female transient orca on Dungeness Spit in
  May 2002
• 1000 ppm PCB
• 12ppm- EPAs standard for marine sediments

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Polychlorinated Biphenyls(PCBs)
Cl
Cl
Cl
Cl
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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

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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

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Generalized Ecological Pyramid
3 Cons.
1 g
2 Consumers
10 g
Primary Consumers
100 g
Primary Producers
1000 g Biomass
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Idealized Puget Sound Ecological Pyramid
Orcas
1 g
Salmon
10 g
Zooplankton
100 g
Phytoplankton
1000 g
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Pollutants

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

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Factors Influencing Impact of Pollutants

• Solubility
• Water soluble pollutants
• Move easily through environment
• Fat soluble pollutants
• Need a carrier
• Long-lasting in bodys fatty tissue
• Persistence
• More stable
• Longer to break down
• More harm it can do

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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

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DDT in a Long Island Estuary(from Woodwell,
Wurster and Isaccson, 1967)
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Idealized Puget Sound PyramidWith PCBs
Orcas
1g
Salmon
10 g
Zooplankton
100 g
Phytoplankton
1000 g
1 g
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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.