Sentence:  You will also take many Flounders ... without a boat, in the drains and watercourses of embanked lands, and even with your hands, for the fish will often seek shelter under your feet if wading; this latter method is termed ‘<WSD>Grabbling</WSD>.' 
Meaning of the word marked with <WSD> tags:  To catch fish by reaching into the water with one's hand.