EFFECTS OF ANTHROPOGENIC NOISEON BALEEN WHALES

PI: Whitlow W. L. Au Co PI: Alison StimpertHawaii Institute of Marine Biology University of Hawaii

BACKGROUND1. Humpback whales are a valuable natural resource of the State

of Hawaii – a multi-million dollar whale watching industry - an important tourist attraction - a part of what makes Hawaii, Hawaii

2. Whales use sounds for a variety of reasonscommunicationsocializationcourtshipsensing of the environment

perhaps foraging by echoranging

3. Before determining effects of anthropogenic noise on whales we need to know what kinds of sounds they produce in various behavioral state and conditions Only songs have been studied to any degree

APPROACH1. Attach acoustic tags to humpback whales using suction cup

mounts a. Bprobe & Dtag in waters of Mauib. Dtag in Stellwagen Bank National Marine Sanctuary

Collaboration:UHNOAAWHOIUNH

2. Analyze data with custom Matlabprograms

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SIGNIFICANCE OF MEGAPCLICK

1. This is first recordings of clicks that can be attributed to a baleen whale

2. The clicks were recorded when the whales were apparently foraging

3. The behavior of the whales while emitting clicks seem verysimilar to the behavior of sperm whales while foraging

4. There is a distinct possibliity that the humpback whales wereechoranging.

a. Possibly trying to find the bottomb. Determining distance from a herring school

Transient-form of Sonar Equation

DT = SE – 2 TL + TS – (No + BW – DI)

Echo energy flux density

Received noise

Issue: Is energy in the echo from potential targets above the received noise?

ocean bottom – megapclick measured at nightherring school

Is the echo audible to the whales?

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Preliminary results: 1. Received levels low (152 +/- 6dB re 1µPa pkpk)2. Whales change group membership frequently3. Sounds common in groups with young animals

MAUI

Whale tagging in Hawaiian waters (Maui)Focus on competitive groups Comparison with feeding ground sounds (AK and Atlantic)

ALOHA!