Lake Georgina use to have them back in the day we use to stay the night by the couple of pine trees at the end and just wade in the lake at night with a eel spear and torch and get them that way..
The fiery ginga
try some of the waterraces out there, under the edges especially if the bottom is muddy. got plenty when I worked in forestry out that way.
Do you need a fishing lience to get fresh water cray fish if at Georgina?