G'day Willo
Not an expert in the worm catching either (i normally have more heads than worms

), but i found keeping them in some cool sand rapped in a dampish cloth and kept out of the sun works well for only the few hours you have to wait for the high tide. Dipping in metho is good if you a going be waiting for a few days before use. Yet i found that i have had live worms for at least 10 hours when i have done this.
ACE
