Wherever you are in Liverpool, you won't be far from the Mersey. Bill Oddie visits the docks, which are full of water even at low tide, because of the sluice. As a result, the docks are like an enormous rockpool, so Bill goes rockpooling - for which he needs special permission. The water is incredibly clear. A prawn nibbles his thumb and he sees pink seaweed, green seaweed, sea anemones, mussels and fish. He has caught some prawns and lovely, delicate red seaweed. The green seaweed is known as gut weed, since it resembles intestines. Bill tries to pick up a shore crab without getting nipped, but the crab has other ideas. A smaller shore crab has a mussel attached to its shell, which it now has to carry about with it. A breadcrumb sponge is supposed to smell like breadcrumbs, but all Bill can smell is soggy sponge.