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Spatial confirmation of vocal communication between a killer whale calf and its natal family. Val Veirs – Colorado College Scott Veirs – Beam Reach Jason Wood – Beam Reach. Session 3aABb3 Wed July 2, 2008 Acoustics ‘08 Paris, France. Resident Killer Whale Family Structure.
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Spatial confirmation of vocal communication between a killer whale calf and its natal family Val Veirs – Colorado College Scott Veirs – Beam Reach Jason 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-22 Oreo J-34 Doublestuf J-38 Cookie
Gato Verde Research Vessel Scott and student, Tim Hunt, are deploying our 30m 4 element hydrophone array. Gato Verde is a 42’ Fontaine-Pajot catamaran powered by electric motors, batteries and a biodiesel electric generator – www.gatoverde.com
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 J-22 (Oreo) and J-34 (Doublestuf) • 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
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 “Y” velocity model Distance derived from Calf’s “X” 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 Distance derived from “Y” velocity model Distance derived from “X” velocity model Mother and brother’s velocity vector relative to the Gato Verde vs. Time
Interpreted orca paths Color coded to denote time Mother and brother Here calf was vocalizing while mother and brother were silent. Calf
1.5 Minutes of Call and Response Play movie
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 x3S2ii 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
Map derived from NOAA Recovery Plan Jan. 2008 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 Graph from the Whale Museum Sightings Database