Overberg Angling

Hi Guys, we were fishing Arendse the other day and when preparing a Tjokka bait and Stef found this fish inside the tjokka, it was right inside the tjokka. Now the questions, does a tjokka take a fish inside the tube to eat it, or was the fish placed there to add weight to the tjokka. If it was placed there what sort of fish is this and where does it come from. It's mouth is underneath it's head and on the photo you can see in the front there is a rim of hard bone from the one side to the other. On top of it's head it has a hard sandpaper type skin and huge eyes........any ideas??

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