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
3 K
2 K
1K
0 1 2 3 4
Time (min)
55
Fre
qu
ency
(H
z)4 K
5K
6 K
EXAMPLE OF A BOAT PASSING BY THE KILO NALU SITE
Soundstarts
EXAMPLE OF HUMPBACK WHALE SONG AT THE KILO NALU SITE
3 K
2 K
1K
00 1 2 3 4 5
Time (min)
Fre
qu
ency
(H
z)
EXAMPLE OF FISH SOUNDS AT THE KILO NALU SITE
3 K
2 K
1K
00 1 2 3 4 5
Time (sec)
Fre
qu
ency
(H
z)
0 100 ms
Frog fish
6 November
100
105
110
115
120
125
130
0 1 2 3 4 5 6 7 8 9 10 12 13 14 15 16 17 18 19 20 21 22 23
Hour (HST)
RM
S (
db
re
1uP
a)
Boat
Snapping shrimp Snapping shrimp
EXAMPLE OF RMS SPL IN A DAY: 6 NOVEMBER
1-7 November
100
105
110
115
120
125
130
135
RM
S (
dB
re
1uP
a)
1 2 3 4 5 6 7
DAY
EXAMPLE OF A WEEK RMS SPL: 1-7 NOVEMBER
Boat in daylight/ snapping shrimp night
SPL 28 February (Mean SPL = 110.4 dB re1uPa)
105
110
115
120
125
130
RM
S (
dB
re1
uP
a)
0 1 2 3 4 5 6 7 8 9 10 12 13 14 15 16 17 18 19 20 21 22 23
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
Recommended
