[Elecraft] Fishy QRM: Who FRTed?

[Lloyd Lachow]

http://209.157.64.200/focus/f-news/1019535/posts

Herrings converse via flatulence, researchers find
 11-11-03



- Herrings appear to be sociable fish who like to
communicate among themselves and use their natural
flatulence to do so, a team of British and Canadian
researchers has reported. 

A report in the British review Biology Letters
describes how the researchers studied the sounds
produced by two kinds of captive, wild-caught herring.


"At night herring squeeze bubbles out of their
swimbladders through an anal pore, producing sounds
not unlike people blowing raspberries," the team of
three recounts. 

The Pacific species (Clupea pallasii) were found to
emit distinctive bursts of pulses, known as fast
repetitive tick (FRT) sounds, mostly at night, lasting
between 0.6 seconds and 7.6 seconds in the 1.7 to 22
kilohertz bands. [Frequency reference = very
appropriate ham radio post, eh?]

   this one has a link to click to listen to the FRTs:

http://www.vanaqua.org/aquanews/benwilson_herringfrts.html

   LL



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