Listen to the Noise in the Yangtze River

The Pilot Expedition team made several recordings of ambient noise in the Yangtze River and Dongting Lake using a variety of towed-hydrophone techniques. The objective of their tests was to determine whether they would be able to hear baiji whistles above the ambient noise created by the KeKao research vessel engine and passing vessels.

Recording Information

These WAV files were digitized from tapes recorded at 48k samples/sec. All were recorded and digitized at the same volume levels, so they are
comparable. The "ambient" noise recordings certainly contain some distant vessel noise, but no ships were seen nearby at the time. They were recorded on DAT tape (48k samples/second) from a Norris 8130 high-frequency towed hydrophone on a 110m tow cable (flat frequency response from 2kHz-160kHz), and they were digitized using an Edirol UA-25 at 48k samples/sec.

Have a listen!

KeKao-Towing
Towing the Norris 8130 hydrophone at 70m behind KeKao

Dongting-Lake drifting brick-barge @100m.WAV
Drifting in Dongting Lake with the Norris 8130 hydrophone deployed from a
small zodiac (engine off). This is the sound of a brick-barge passing by
approximately 100m away

Dongting-Lake drifting ambient-noise heavyRain @100m.WAV
Drifting in Dongting Lake with the Norris 8130 hydrophone deployed a small floating zodiac. This is the sound of heavy rain conditions

Dongting-Lake drifting ambient-noise lightRain
Drifting in Dongting Lake with the Norris 8130 hydrophone deployed from a
small floating zodiac. This is the sound of light rain conditions

YueyangSmallBoat
Drifting in Yueyang section with the Norris 8130 hydrophone deployed from a small floating zodiac. This is the sound of a small boat passing by 100m away

YangtzeChannelLargeShip
Drifting in the Yangtze channel with the Norris 8130 hydrophone deployed
from a small floating zodiac. This is the sound of a large ship passing by
approximately 600m away

YangtzeChannelLargeShip
Drifting in the Yangtze channel with the Norris 8130 hydrophone deployed
from a small floating zodiac. This is the sound of a large ship passing
nearby the zodiac

Yueyangambient-noise
Drifting in Yueyang section with the Norris 8130 hydrophone deployed from a small floating zodiac.

YueyangLargeShip
Drifting in the Yueyang section with the Norris 8130 hydrophone deployed
from a small floating zodiac. This is the sound of a large ship passing by
approximately 800m away


YueyangMedShip
Drifting in the Yueyang section with the Norris 8130 hydrophone deployed
from a small floating zodiac. This is the sound of a medium sized ship
passing by approximately 150m away

YueyangSmallBoat
Drifting in the Yangtze channel with the Norris 8130 hydrophone deployed
deployed from a small floating zodiac. This is the sound of a small boat
passing by approximately 50m away