Echolocation and strategy used by Southern Resident Killer Whales (Orcinus orca) during foraging. Wilfredo Santiago Benítez Universidad Metropolitana San Juan, Puerto Rico Wilfredo Santiago Benítez Universidad Metropolitana San Juan, Puerto Rico

Introduction  Differences around the world  Specializations  Top Predator  Differences around the world  Specializations  Top Predator

Introduction  Research on echolocation and foraging 1. Barrett-Lennard, different sonar use between fish-eating and mammal- eating killer whales 2. Baird, Describe the behavior performed between residents and transients  Research on echolocation and foraging 1. Barrett-Lennard, different sonar use between fish-eating and mammal- eating killer whales 2. Baird, Describe the behavior performed between residents and transients

Introduction 3. Baird, Concluded that deep dives, rapid changes on direction and speed and tail-lobbing are characteristics on foraging behavior on residents 4. Nottestad, 2002 and Au, Both agreed that salmon cannot pick up the echolocation of the whales and that may be a reason for different on foraging strategy between orcas from Northwestern Washington and Norway 3. Baird, Concluded that deep dives, rapid changes on direction and speed and tail-lobbing are characteristics on foraging behavior on residents 4. Nottestad, 2002 and Au, Both agreed that salmon cannot pick up the echolocation of the whales and that may be a reason for different on foraging strategy between orcas from Northwestern Washington and Norway

Introduction  Echolocation - a high-pitched sound (usually clicks) is sent out by the whale. The sound bounces off the object and some returns to the whale. The whale interprets this returning echo to determine the object's shape, direction, distance, and texture.  Types- 1.Foraging 2.Traveling  Clicks Trains - low-frequency clicks (called a train) produced by the animal that bounces off objects and reflects (echoes) back to the whale.  Echolocation - a high-pitched sound (usually clicks) is sent out by the whale. The sound bounces off the object and some returns to the whale. The whale interprets this returning echo to determine the object's shape, direction, distance, and texture.  Types- 1.Foraging 2.Traveling  Clicks Trains - low-frequency clicks (called a train) produced by the animal that bounces off objects and reflects (echoes) back to the whale.

Materials and Methods  Marantz  Recorder Model PMD660  Audacity for Macintosh Apple  Operating System.  Position Observation  Photos  Video  Marantz  Recorder Model PMD660  Audacity for Macintosh Apple  Operating System.  Position Observation  Photos  Video

Materials and Methods  Analyzing clicks - each file consist a minute, each minute was analyzed in Audacity  by zooming in and dividing the minute by 5 seconds an area and counted each click

Results  Echolocation clicks: 1.Foraging - Ten minute recording (Oct. 6) had 4,162 clicks (416.2 clicks per minute) 2.Traveling - Ten minute recording (Oct. 21) had 155 clicks (15.5 clicks per minute) 3.Rare pattern of clicks trains observed during foraging but not observed in traveling  Echolocation clicks: 1.Foraging - Ten minute recording (Oct. 6) had 4,162 clicks (416.2 clicks per minute) 2.Traveling - Ten minute recording (Oct. 21) had 155 clicks (15.5 clicks per minute) 3.Rare pattern of clicks trains observed during foraging but not observed in traveling

Figure 2. Print Screen of an echolocation minute recorded on October 6, This example shows the quantity of clicks in only one minute.

Figure 3. Print screen with a highlighted zone were the pattern of clicks was observed during a minute of a foraging record on October 6, 2005.

Histogram Table 1. Numbers of echolocation clicks from 11:44 am to 11:54 of the recording of October 6, 2005.

Results  Foraging Strategy 1.Males - Offshore (1- 2) 2.Females & Calves - Inshore (1-3) 3.Females/ Juveniles - Middle (2-4) Coast Sea Blue – Adult Male Red- Females or Juveniles Yellow - Calves

Results Blue – Adult Male Red- Females or Juveniles Yellow - Calves.

Figure 4. Print screen of an echolocation minute recorded on October 21, The picture clearly shows the lack of clicks during the entire duration on the minute.

Histogram Table 2. Numbers of echolocation clicks from 12:24 pm to 12:33 pm from October 21, 2005.

Conclusion  Echolocation clicks - used more during foraging than traveling  Pattern of clicks trains observed more during foraging  Foraging strategy - at least three types of groups were observed during foraging

Reference  Au, W.W.L., J.K.B. Ford, J.K. Horne and K.A. Newman-Allman Echolocation signals of free-ranging killer whales (Orcinus orca)and modeling of foraging for Chinook salmon (Oncorhynchus tshawytscha). J. Acoust. Soc. Am. 115 (2). February,  Baird, R.W The killer whale- foraging specializations and group hunting. Pages in Cetecean societies: field studies of dolphins and whales. Edited by J. Mann, R.C. Connor, P.L. Tyack and H. Whitehead. University of Chicago Press.  Baird, R.W., M.B. Hanson, E.E. Ashe, M.R. Heithaus and G.J. Marshall Studies of foraging in “ southern resident ” killer whales during July 2002: Dive depths, burst in speed, and the use of a “ crittercam ” system for examining subsurface behavior. Report for the NMML, NMFS. February 28,  Barrett-Lennard, L.G., J.K.B. Ford, and K.A. Heise The mixed blessing of echolocation: differences in sonar use by fish-eating and mammal-eating killer whales. Animal Behaviour. 51:  Domenici, P., R.S. Batty, and T. Simila, and E. Ogam Killer Whales (Orcinus orca) feeding on schooling heering (Clupea harengus) using underwater tail-slaps: Kinematics analyses of field observations. The Journal of Experimental Biology 203:  N ø ttestad, L., A. Fern ö, and B.E. Axelsen Digging in the deep: killer whales ’ advanced hunting tactic. Polar Biology 25:  Au, W.W.L., J.K.B. Ford, J.K. Horne and K.A. Newman-Allman Echolocation signals of free-ranging killer whales (Orcinus orca)and modeling of foraging for Chinook salmon (Oncorhynchus tshawytscha). J. Acoust. Soc. Am. 115 (2). February,  Baird, R.W The killer whale- foraging specializations and group hunting. Pages in Cetecean societies: field studies of dolphins and whales. Edited by J. Mann, R.C. Connor, P.L. Tyack and H. Whitehead. University of Chicago Press.  Baird, R.W., M.B. Hanson, E.E. Ashe, M.R. Heithaus and G.J. Marshall Studies of foraging in “ southern resident ” killer whales during July 2002: Dive depths, burst in speed, and the use of a “ crittercam ” system for examining subsurface behavior. Report for the NMML, NMFS. February 28,  Barrett-Lennard, L.G., J.K.B. Ford, and K.A. Heise The mixed blessing of echolocation: differences in sonar use by fish-eating and mammal-eating killer whales. Animal Behaviour. 51:  Domenici, P., R.S. Batty, and T. Simila, and E. Ogam Killer Whales (Orcinus orca) feeding on schooling heering (Clupea harengus) using underwater tail-slaps: Kinematics analyses of field observations. The Journal of Experimental Biology 203:  N ø ttestad, L., A. Fern ö, and B.E. Axelsen Digging in the deep: killer whales ’ advanced hunting tactic. Polar Biology 25:

Acknowledgements  Beam Reach Program Board and Instructors -Dr. Scott Veirs, Dr. Val Veirs, Michael Dougherty  USDA Public Service Leaders Scholarship.  Captain Todd Schuster -Gato Verde Sailing Adventures  Mrs. Leslie Veirs, Dr. Annie Reese, and Liam Reese  My peers- Brett Becker, Celia Barroso, Laura Christoferson, Nicole Lee, and Courtney Kneipp.  Dr. Robin W. Baird  Dr. Richard Osborne - The Whale Museum  Dr. Fred Felleman  Kenneth C. Balcomb III - The Center of Whale Research  Dr. David Bain  Judy Mickel, Kevin Wood, Bob McLaughlin, and Rachael Griffin  My family & friends  To my late friend, Adamaris  Beam Reach Program Board and Instructors -Dr. Scott Veirs, Dr. Val Veirs, Michael Dougherty  USDA Public Service Leaders Scholarship.  Captain Todd Schuster -Gato Verde Sailing Adventures  Mrs. Leslie Veirs, Dr. Annie Reese, and Liam Reese  My peers- Brett Becker, Celia Barroso, Laura Christoferson, Nicole Lee, and Courtney Kneipp.  Dr. Robin W. Baird  Dr. Richard Osborne - The Whale Museum  Dr. Fred Felleman  Kenneth C. Balcomb III - The Center of Whale Research  Dr. David Bain  Judy Mickel, Kevin Wood, Bob McLaughlin, and Rachael Griffin  My family & friends  To my late friend, Adamaris

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