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Spatial confirmation of vocal communication between a killer
whale calf and its natal familyVal Veirs – Colorado College
Scott Veirs – Beam ReachJason Wood – Beam Reach
Session 3aABb3 Wed July 2, 2008 Acoustics ‘08 Paris, France
Resident Killer Whale Family Structure
• Site fidelity year to year• Specialize on foraging for fish• Progeny never leave their mother• Residents are inter-related
matriarchal families• Vocalizations are complex and
frequent• Vocalizations form a vocal ‘clan’
unique to geographic region
Beam Reach Researchers 9/1/2007
San Juan Island, Washington
10 nm
Three Members of J-Pod
J-38Cookie
J-34Doublestuf
J-22Oreo
Gato Verde Research Vessel
Gato Verde is a 42’ Fontaine-Pajot catamaran powered by electric motors, batteries and a biodiesel electric generator – www.gatoverde.com
Scott and student, Tim Hunt, are deploying our 30m 4 element hydrophone array.
Localizing Orca Calls• Calls were recorded at 50 kHz sample rate• Calls were localized using Ishmael and using
software written by Val
Field Observations – 17:30 on 9/1/07
• We have been following J-pod for several hours• About 17:00 (9/1/07) the spread out pod appeared to reverse
direction and start heading SE• Some whales are several hundred meters off our beam and
were photographed at 17:29• At nearly 17:30 we heard louder and louder calls from the
hydrophones and noticed an individual orca swimming toward our port stern.
• A photo of this whale was taken at 17:31.• Just before it seemed the whale would contact us, it turned,
dove, and then surfaced ahead of us on our port quarter• Over the next minutes, it swam back in the direction of the
more distant orcas.
Photo Identification
• Based on our photos, we identify three orcas: the mother J-22 and her two youngsters J-34 and J-38• These IDs were confirmed by staff at the Center for Whale Research on San Juan Island
J-22 (Oreo) and J-34 (Doublestuf)
Localized Calls – 6 minutes @17:30•54 calls were localized using our 4-element towed hydrophone array
•The array has a length of 40m and is towed off the port stern of the Gato Verde
•The locations of calls are colored based on their time in seconds after 17:25
Kinematically Reasonable Whale Paths
In order to separate these localized calls into those of J-34, the calf that approached us, and its mother (J-22) and/or brother (J-24), we constructed velocity profiles that minimized changes in velocity and limited velocity to slow travel speeds as this is what we observed during this encounter.
J-38 –”Cookie’s” Path
Distance derived from Calf’s “X” velocity model
Distance derived from Calf’s “Y” velocity model
Calf’s velocity vector relative to the Gato Verde vs. Time
Path of J-22 (“Oreo”) and J-32 (“DoubleStuf”)Two whales traveling together
Mother and brother’s velocity vector relative to the Gato Verde vs. Time
Distance derived from “X” velocity model
Distance derived from “Y” velocity model
Interpreted orca paths
Mother and brother
Calf
Color coded to denote time
Here calf was vocalizing while mother and brother were silent.
1.5 Minutes of Call and Response
Play movie
Calf Calls
Mother/Brother Calls
Orca Communication
Calf’s Calls Near the Array
Call and Response [Calf Mother/Brother]: S2ii [S2ii S6] S6 S2ii x5 [S2ii S6] S6 S6 [S2ii ??] S2i (Pause) [S2ii S6] [?? S6 ?? S6 ??] [S12 S2ii S2ii x3 S2ii S2iix3] [S2ii S2ii]
Acknowledgements
We sincerely thank: • Student researchers of the fall 2007 class, Beam
Reach Marine Science and Sustainability School (including Kenna Lehmann!)
• Captains Todd Shuster and Mike Kramer• Dr. Shannon Fowler
More information and research results at:• beamreach.org and beamreach.org/071
Localization – Crosspower spectra and Hyperbolic intersections
Southern Resident Orcas
•Winter Range – Monterey Bay to Queen Charlotte Islands
•Summer Range – Inland waters of Puget Sound and southern Georgia
Strait – the Salish Sea
Salish Sea Sightings
Map derived from NOAA Recovery Plan Jan. 2008
Graph from the Whale Museum Sightings Database