George,  When I'm on vacation I usually freeze them or put them on ice,
and then remove the animal later with water pressure.  I use a set of
screens with 3 different size holes to sort them.  Window screen at the
bottom 1/8 inch mesh in the middle and 1/4 inch in the top screen.  I
use a wire net with a handle to catch them.  I have to keep my answers
short or my message won't go.  Any more questions?
 
Bob
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