Dear Ross,
It has been a while since I looked at this issue, but try the following as a
starting point:
1) A company called ORE International Inc., Box 709, Falmouth heights Road,
Falmouth, Massachusetts 02541, USA, Fax: 508-540-3835.  They use ultrasonic
tracking devices and either have release units themselves, or know where you
can find them.
2) A company called VEMCO, They deal with ultrasonic equipment, fish
tracking gear, telemetry etc.  The president, Fred Voegeli, is very helpful,
I have used their equipment for fish telemetry for years and always receive
excellent advise and assistence.  Try Vemco, 3895 Shad Bay, RR # 4 Armdale,
Halifax, Nova Scotia, B3L 4J4, Canada, Email: [log in to unmask]
3) Try looking through a journal called "Sea Technology" (if it is still in
print?!), there are always plenty of ads in there from companies in this
field (oil- gas exploration, hydrography).

Hope this helps, best of luck

Dirk C. Zeller
Research Officer

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