The Examination of killer whale (Orcinus orca) call duration due to boat noise and vessel count By: Peter Valenzuela Beam Reach Spring 2009

Introduction There are 3 different Ecotypes of Killer Whales: –Offshore: Thought to be fish/shark Eating –Transients: Mammal Eating –Residents: Fish Eating The Southern Resident Killer Whales (SRKW) are our focus of study Area of Study: San Juan Islands and Haro Strait Three Major Threats to Killer Whales: –Toxins, Prey Availability, and Noise

Killer Whales and Sound Sound is primary source of communication between the SRKW Extra human noise potential to disrupt SRKW normal activities John Ford Classified 3 types of Sounds: clicks, whistles, and pulsed calls Pulsed calls are most abundant and characterized class of vocalization used by the SRKW

S1 Call

Other Studies done on Call Duration Andrew Foote: Boat Presents or Absence- found significance in call duration to boat presence Marla Holt: Measured boat noise to see if it affects call duration- found no significance

Methods Looked for behavior states –Traveling, Resting, Milling, Foraging, Play Counted boats (within.5 Nautical mile or approximately 1000 meters) Measured Boat noise Used Audacity program for analysis

Spectrogram in Audacity

Spectrogram in Audacity con.

Results P-value: & Sample Size: 181

P-value: 0.485

P-value < 0.001

Comparison Andrew Foote (n=135) –Found Significance using a Mann Whitney U test between boat presence/absence and Call duration Peter Valenzuela (n=181) –Did same test and found no significance Marla Holt (n=104) –Found no significance using a linear regression between boat noise and call duration Peter Valenzuela (n=181) –Found Significance using the same test, but varies by behavior

Behavior Breakdown! P-ValueTravelingForagingPlay CD vs VC CD vs BN VC vs BN< Sample Size

Thank You! Beam Reach –Dr. Jason Wood –Dr. Val Veirs –Dr. Scott Veirs Cpt. Todd Shuster Cpt. Mike Kramer My Class Mates

Questions?