I haven't tried the electric shock treatment, but I have tried immersion in
water (I think my worms have breathing apparatus because they won't
surface and they don't drown). Spraying with heavy droplets rather than a
fine mist seems to bring them to the surface - perhaps it simulates rain -
and they tend to surface at night anyway. However grabbing them with
tweezers hasn't proved a good strategy - what's worse than an earthworm
in a colony of pygmies - half an earthworm! Since pygmy colonies seem
to have a short useful life, I am using barrier methods to prevent new
infections and slowly replacing old colonies with new ones started from
gemmae. My worms seem to be territorial - only one adult per pot.
In a year or two's time, I should have at my disposal the ultimate earthworm
nightmare - New Zealand Flatworms are now common in Scotland and
making their way South.
Gooid Growing, Nigel Hurneyman