You can eat Dogfish I have and their OK in taste but have poor texture, Rig is good eating and is often used in Fish and chip shops. Elephant fish is the best eating fish around Canterbury though.
Yep October to March is the best time for surfcasting around Timaru. Moki are around all year though. If your going to try the Breakwater area Id move down the beach toward patiti point a few hundred meter’s as there are still Moki there but a lot less snags.