Killer Whale Vocal Response to Vessel Traffic Celia

• Southern resident killer whales (SRKW) declared “depleted” under the Marine Mammal Protection

Population Structure and Communication • Different pods (J-pod, K-pod, and L-pod) • Different dialects

Research that sparked my curiosity • Vessel traffic has increased five fold over between

My questions • Do SRKWs exhibit short-term changes in call duration in response to

How did I conduct my experiment? • I attempted to recreate Andrew Foote’s and

How did I conduct my experiment? • Calculated call duration of the second harmonics

What did I find? • The mean I calculated for S 16 calls compares

What did I find? • Average S 1 call duration in the presence of

Problems and conclusions • I, unlike Foote et al. , was generally unable to

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Killer Whale Vocal Response to Vessel Traffic Celia Barroso Beam Reach Marine Science and Sustainability School Fall 2005 California State University, Long Beach, California

• Southern resident killer whales (SRKW) declared “depleted” under the Marine Mammal Protection Act • Possible causes according to NOAA/NMFS Conservation Plan: – Pollutants/Contaminants (c. f. PCB, DDT) – Decreased prey availability – Anthropogenic noise pollution

Population Structure and Communication • Different pods (J-pod, K-pod, and L-pod) • Different dialects • Pod specific calls (Ford, 1990) – S 1 (J-pod, K-pod) – S 16 (K-pod, L-pod) – S 19 (L-pod) • Dominant calls

Research that sparked my curiosity • Vessel traffic has increased five fold over between 1990 and 2000 (Foote et. al. , 2004) • During the period of 2001 -2003 all pods exhibited a significant (15%) increase in call duration in the presence of whalewatching vessels.

My questions • Do SRKWs exhibit short-term changes in call duration in response to daily exposure to vessel noise? – Do they modify their calls to avoid masking by boat noise? • Examples: motor , ship , quiet

How did I conduct my experiment? • I attempted to recreate Andrew Foote’s and Richard Osbourne’s published research over a shorter time scale. • We used a hydrophone, amplifier and digital recorder to receive and record the sounds. • Viewed spectrograms of S 1, S 16, and S 19

How did I conduct my experiment? • Calculated call duration of the second harmonics for S 1 and S 16 calls, the third harmonic for S 19 high frequency component and fundamental for low frequency component S 19 Low S 16 S 19 High

What did I find? • The mean I calculated for S 16 calls compares to • the mean S 16 call published by Foote et. al. I did not record S 16 or S 19 calls that were quantifiable using my methods when vessels were absent

What did I find? • Average S 1 call duration in the presence of vessels is 1. 17 s and 1. 105 s in the absence of vessel noise.

What did I find? • No trends

Problems and conclusions • I, unlike Foote et al. , was generally unable to • distinguish which pod I was listening to More observations are needed – – – Observations during peak whale-watching season 24 hr observations Observations regarding activities and call duration • Perhaps SRKWs don’t modify their calls in response to vessel noise