Hi David and other Scuba-ers,

For collecting micro-shells while scuba diving I use 3
types of methods that normally result in live
collected material. This is particularly importunate
since most of live collected micros will still have
there prots, sculpture, natural colour and last but
not the lease the live animal. All these
characteristics will help you a lot to identify your
finds. From my experience most of the dead micros
found in shell grit do not reveal these
characteristics and sometimes one has to find a couple
of dozen shells to correctly identify a single species
(this is, if it as problematic one :-)).
The 3 methods I use are the following:

1) – To collect micros that normally live buried I
first select a spot (normally composed of fine sandy
mud) which I consider is suitable or have a sheller's
feeling that it will be productive. By using a small
hand dredge I slowly dredge the first 5 to 10 cm of
subtract. As the net gets filled with shell derbies
and eventually micros I clean the hand dredge into a
zip-lock bag and continue the activity. I have had
very good results with this method and have managed to
build up quite a nice Pyramidellidae and especially
Turridae collection.

2) – To collect micros that normally live on rock
platforms and caves covered algae, incrusting algae
and other bentic life I normally use a small brush,
with one hand, to gently brush the surface of theses
subtracts into a fine mash net which I hold with my
other hand. This method is pretty good, especially for
Rissoas, Chauvetias, Gibberulas and also, for those
who are interested, in micro Opistobranchia

3) – The third method I use, normally while filed
working for the university, is a sort of suction tube
device liked to a scuba bottle and ending with a fine
marsh net where all the material that has been sucked
through the tube ends up. This method has an
inconvenient and for better results 2 people are
required for the job (1 to hold the tube in the
correct position and another to open pressure and
close pressure on the scuba bottle). This method has
good results to but requires a different diving
planning ....

Other ways to obtain live micro shells without scuba
equipment is the washing of intertidal algae and
method 2 can also be use in the intertidal zone being
quite productive. A good source for deep water micros
is to contact fishermen and ask them to keep the
leftovers from gill and tangle nets so that this way
you may be able to sort them at home or in the lab.

Hope you and others have a wonderful time micro
collecting. Haven't been in the water for almost a
month and am going crazy :-),
Um abraco,

Carlos Afonso (South, Portugal)



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