 Bengali cuisine is rich and varied with the use of many specialized spices and flavours.Fish is the dominant source of protein, cultivated in ponds and fished with nets in the fresh-water rivers of the Ganges delta.More than 40 types of mostly freshwater fish are common, including carp varieties like "rui" (rohu), "katla", "magur" (catfish), "telapia", "bhetki", "koi", "lyata", "tangra", "sole", "shingi", "pabda" etc.