Kilo Nalu Nearshore Reef ObservatoryAcoustic Monitoring

The Soundscape of a Nearshore Reef near an Urban Center

Whitlow W. L. AuMarine Mammal Research ProgramHawaii Institute of Marine BiologyUniversity of Hawaii

KILO NALU & MAKAPUU SITES

Makapuu EAR

22 m depth690 m off-shore

Sample rate = 24,000 Hz = 4.2 Gbytes/day = 124 Gbytes/mn

Modified EAR

Background

1. Ecological Acoustic Monitor (EAR) modified and deployed at

Kilo Nalu site – up and running 1st week in Nov, 2008

2. Sounds being heard

Boats, boats, boats and more boats.humpback whalesdolphin echolocation clickssnapping shrimp rain

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EXAMPLE OF A BOAT PASSING BY THE KILO NALU SITE

Soundstarts

EXAMPLE OF HUMPBACK WHALE SONG AT THE KILO NALU SITE

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EXAMPLE OF FISH SOUNDS AT THE KILO NALU SITE

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Frog fish

6 November

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Snapping shrimp Snapping shrimp

EXAMPLE OF RMS SPL IN A DAY: 6 NOVEMBER

1-7 November

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EXAMPLE OF A WEEK RMS SPL: 1-7 NOVEMBER

Boat in daylight/ snapping shrimp night

SPL 28 February (Mean SPL = 110.4 dB re1uPa)

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Hour (HST)

28 February

Boats & Humpback Whales Hump & shrimpHump & shrimp

EXAMPLE OF MIXTURE OF SOUNDS IN WINTER

POSSIBLE PRODUCTS

1. Obtaining acoustic signature of small boatNavy has many signatures of ships – not small boatsHome land security or coastal security issues

2. Long term – time series of snapping shrimp soundsbiological indicator of negative effects on environmenti.e. EARs data from Kure and Pearl and Hermes show lower levels for up to a day after a storm.

3. Behavioral pattern of Humpback whales off Oahudata for management of HIHWNMSarrival and departure off Oahueffects of anthropogenic noise