"It is certainly questionable and unsafe behaviour around water. They were putting their lives on the line for the sake of a bucket or two of whitebait," Mr Claridge said.
"It's not uncommon for a whitebaiter to be in the water but those conditions looked less than ideal for whitebaiting, certainly at a lake mouth like that when there's quite a bit of white water with waves crashing in and the current potentially moving out. It looks really dangerous."
Mr Claridge said he urged whitebaiters and anglers "to stay on dry land wherever possible when it comes to land-based fishing".
"Certainly this wasn't the case on Friday although I know how things work for whitebaiters," he said.
"The difficulty is that they're caught up in the moment and that's when people need to be really clear about just what the risks are. But generally, men in New Zealand under-estimate the risks associated with being around water.
"And if you look at what those guys were wearing, if they got knocked over they would really struggle to regain their footing due to the weight of the clothing they have on," Mr Claridge said. "In all likelihood it would be very difficult to keep your head above water in that gear in those conditions.
"I've seen examples where people have tested wearing a lot of clothes in just flat calm water but that's really wholly different," he said.
"It would be very difficult to muster the strength and the balance to be able to regain your footing, and that's after getting through the shock of cold water. You should never under-estimate the effect of that hitting the body."
The whitebait season for most of New Zealand runs until November 30.