Differences in diving behavior of wild and captive populations of Phoca vitulina

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Differences in diving behavior of wild and
captive populations of Phoca vitulina

• Andrew Haertel
• Oceans of Fun
• Mentors Kelly, Bonnie, and Tami

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• Harbour seals (Phoca vitulina)

• 2-6 minute dives
• 1 minute breaks
• 40-90 of dives less than 4 minutes
• 80 of time underwater
• Most dives are under 20 meters

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Diving Response

• Theoretical limit 8.9 minutes for 80 kg seal
• Hold breath for 20 minutes
• Dive 90 meters
• Due to
• Bradycardia
• Vasoconstriction
• Myoglobin

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Biological Rationale

• Factors contributing to diving behavior
• Predators
• Food

• In captivity,
• No predators
• No need for
• extended foraging
• trips

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Hypothesis

• Phoca vitulina living in captivity will spend
  less time diving underwater and conduct more
  frequent dives which are shallower and shorter
  than Phoca vitulina in the wild
• Specifically
• Dive length
• Time spent on surface
• Dives per hour
• of dives less than 4 minutes
• of dives shallower than 20 meters
• Max Depth
• Recorded Behaviors

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Methods

• 75 ethograms
• Resting hauled out, swimming on surface, swimming
  underwater, exploring enrichment, coasting,
  bottling, vocalizing, floating

• 25 Ethograms
• Diving behavior recorded
• Dives counted
• Length of each dive timed

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Animal Subjects

• Satara
• 13 year old female
• 106 pounds
• Lives with 9 California Sea Lions

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Animal Subjects

• Ringo
• Older Male
• Blind
• Atlantic Harbor Seal
• Sydney
• Female
• Pacific Harbor Seal
• Pender
• Male
• Pacific Harbor Seal

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Results
Average Dive Length
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Results
Average time spent on surface of water compared
to time underwater
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Results
Amount of Dives per hour
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Results
Percent of dives less than four minutes
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Results
Maximum depth during dives
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Results
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Results
Average time spent on surface of water compared
to time underwater
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Discussion

• Captivity
• No predation/no food shortage
• Less dive response
• Shorter, shallower dives

• Agreement among
• different figures

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Assumptions

• Literature value error bars
• Loss of ability to dive deep
• Size of animals
• Only 4 animals
• Pool size limited
• Observational Study
• Need to alter variables to test experimentally

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Questions!