![Page 1: Zipfs Slope Investigating the southern residents repertoire with Information Theory Kenna Lehmann Beam Reach Marine Science and Sustainability School -](https://reader036.vdocuments.us/reader036/viewer/2022062511/55173d4a55034603568b6209/html5/thumbnails/1.jpg)
Zipf’s Slope
Investigating the southern residents’
repertoire with Information
Theory
Kenna Lehmann
Beam Reach Marine Science and Sustainability School - beamreach.org/071
![Page 2: Zipfs Slope Investigating the southern residents repertoire with Information Theory Kenna Lehmann Beam Reach Marine Science and Sustainability School -](https://reader036.vdocuments.us/reader036/viewer/2022062511/55173d4a55034603568b6209/html5/thumbnails/2.jpg)
Communication
• The passing of information from one individual (the sender) to another (the receiver)
Sender Receiver
Information
![Page 3: Zipfs Slope Investigating the southern residents repertoire with Information Theory Kenna Lehmann Beam Reach Marine Science and Sustainability School -](https://reader036.vdocuments.us/reader036/viewer/2022062511/55173d4a55034603568b6209/html5/thumbnails/3.jpg)
Communication Channels
• Different senses (i.e. sight, sound, smell)
• Different environments (i.e. the ocean, the forest, the savanna)
![Page 4: Zipfs Slope Investigating the southern residents repertoire with Information Theory Kenna Lehmann Beam Reach Marine Science and Sustainability School -](https://reader036.vdocuments.us/reader036/viewer/2022062511/55173d4a55034603568b6209/html5/thumbnails/4.jpg)
Background
• Orcas are highly social and vocal– Communication is key in maintaining social
interactions
• Call meanings have never been determined– No correlation between behavior and call-type
![Page 5: Zipfs Slope Investigating the southern residents repertoire with Information Theory Kenna Lehmann Beam Reach Marine Science and Sustainability School -](https://reader036.vdocuments.us/reader036/viewer/2022062511/55173d4a55034603568b6209/html5/thumbnails/5.jpg)
Questions
• What information do orcas send in their calls?
• How much information do orcas send in their calls?
• How is that information organized?
![Page 6: Zipfs Slope Investigating the southern residents repertoire with Information Theory Kenna Lehmann Beam Reach Marine Science and Sustainability School -](https://reader036.vdocuments.us/reader036/viewer/2022062511/55173d4a55034603568b6209/html5/thumbnails/6.jpg)
Information Theory• Quantitative way to analyze a
communication system
• As designed by Shannon and Weaver (1949) – Determines how a communication system is
internally organized
• Zipf’s slope: indication of a repertoire’s potential to contain information
![Page 7: Zipfs Slope Investigating the southern residents repertoire with Information Theory Kenna Lehmann Beam Reach Marine Science and Sustainability School -](https://reader036.vdocuments.us/reader036/viewer/2022062511/55173d4a55034603568b6209/html5/thumbnails/7.jpg)
Calculating Zipf’s slope
![Page 8: Zipfs Slope Investigating the southern residents repertoire with Information Theory Kenna Lehmann Beam Reach Marine Science and Sustainability School -](https://reader036.vdocuments.us/reader036/viewer/2022062511/55173d4a55034603568b6209/html5/thumbnails/8.jpg)
Zipf’s Slope
![Page 9: Zipfs Slope Investigating the southern residents repertoire with Information Theory Kenna Lehmann Beam Reach Marine Science and Sustainability School -](https://reader036.vdocuments.us/reader036/viewer/2022062511/55173d4a55034603568b6209/html5/thumbnails/9.jpg)
Balance between
![Page 10: Zipfs Slope Investigating the southern residents repertoire with Information Theory Kenna Lehmann Beam Reach Marine Science and Sustainability School -](https://reader036.vdocuments.us/reader036/viewer/2022062511/55173d4a55034603568b6209/html5/thumbnails/10.jpg)
Too diverse
Y=-.5+B
![Page 11: Zipfs Slope Investigating the southern residents repertoire with Information Theory Kenna Lehmann Beam Reach Marine Science and Sustainability School -](https://reader036.vdocuments.us/reader036/viewer/2022062511/55173d4a55034603568b6209/html5/thumbnails/11.jpg)
Too unified
Y=-1.5x+B
![Page 12: Zipfs Slope Investigating the southern residents repertoire with Information Theory Kenna Lehmann Beam Reach Marine Science and Sustainability School -](https://reader036.vdocuments.us/reader036/viewer/2022062511/55173d4a55034603568b6209/html5/thumbnails/12.jpg)
Methods
Additional recordings
![Page 13: Zipfs Slope Investigating the southern residents repertoire with Information Theory Kenna Lehmann Beam Reach Marine Science and Sustainability School -](https://reader036.vdocuments.us/reader036/viewer/2022062511/55173d4a55034603568b6209/html5/thumbnails/13.jpg)
Call Types
![Page 14: Zipfs Slope Investigating the southern residents repertoire with Information Theory Kenna Lehmann Beam Reach Marine Science and Sustainability School -](https://reader036.vdocuments.us/reader036/viewer/2022062511/55173d4a55034603568b6209/html5/thumbnails/14.jpg)
![Page 15: Zipfs Slope Investigating the southern residents repertoire with Information Theory Kenna Lehmann Beam Reach Marine Science and Sustainability School -](https://reader036.vdocuments.us/reader036/viewer/2022062511/55173d4a55034603568b6209/html5/thumbnails/15.jpg)
Ford (1991)
![Page 16: Zipfs Slope Investigating the southern residents repertoire with Information Theory Kenna Lehmann Beam Reach Marine Science and Sustainability School -](https://reader036.vdocuments.us/reader036/viewer/2022062511/55173d4a55034603568b6209/html5/thumbnails/16.jpg)
What?
• The southern residents’ repertoire has a Zipf’s slope that is steeper than optimum
• Decreased from 1979-1983 to 2006-2007
• Repertoire is too unified (i.e. repetition)
![Page 17: Zipfs Slope Investigating the southern residents repertoire with Information Theory Kenna Lehmann Beam Reach Marine Science and Sustainability School -](https://reader036.vdocuments.us/reader036/viewer/2022062511/55173d4a55034603568b6209/html5/thumbnails/17.jpg)
Why?
• Too much background noise in the communication channel?
• Contact calls?
• Have Soundwatch guidelines decreased boat noise in recent years?
![Page 18: Zipfs Slope Investigating the southern residents repertoire with Information Theory Kenna Lehmann Beam Reach Marine Science and Sustainability School -](https://reader036.vdocuments.us/reader036/viewer/2022062511/55173d4a55034603568b6209/html5/thumbnails/18.jpg)
Further Research
• Comparing different populations and species
• Use Shannon and Weaver’s Information Theory to evaluate the internal organization of the repertoire
![Page 19: Zipfs Slope Investigating the southern residents repertoire with Information Theory Kenna Lehmann Beam Reach Marine Science and Sustainability School -](https://reader036.vdocuments.us/reader036/viewer/2022062511/55173d4a55034603568b6209/html5/thumbnails/19.jpg)
Acknowledgments
John Burt for Syrinx, Scott and Val Veirs for Call Tutor and guidance, FHL computer team for helping with the many computer glitches, team VaTo, Leslie Veirs for the goodies, Mike for not crashing the boat (oh wait), my parents for obvious reasons, Shannon Fowler for the excellent feedback on my papers and life, Jason Wood for the support, feedback, brainstorming and putting up with us
And to my favorite whales: Liz, Heather, Elise, and WesFor the good times