[Coral-List] Damaged Temperature Loggers

[Natalie Andersen]

Dear Coral List

I recently deployed four HOBO Water Temperature Pro v2 data loggers
(U22-001) in Pemba, Tanzania at depths of 1 m, 7 m, 15 m and 25 m. They had
been in-situ three months when a colleague went to check on them last week
and found that the two at 15 m and 25 m had suffered some kind of
catastrophic failure, I have attached photos. The two at 1 m and 7 m are in
good condition.
I had not put them in any kind of protective case as the boot manufactured
by Onset is advertised as being necessary only in harsh conditions, which I
didn't consider to be Pemba.

The manufacturer has stated they have never seen anything like this and
does not believe it to be a problem with the instrument. They have
suggested the cause is propeller damage (the loggers were too deep) and
marine life. I find it hard to believe that I am the only incidence of
predation given that these loggers are frequently used throughout the
tropics.

I was therefore wondering if anyone had experienced anything similar?

Also I would appreciate if anyone has any recommendations for similar,
alternative instruments as I am due to deploy more but am hesitant at the
moment.

Thank you

Natalie

-- 
Natalie Andersen
PhD Student
University of York
Department of Environment and Geography
University of York
Wentworth Way
York YO10 5NG