fishery -- n. a part of the ocean where fish and other sea creatures are caught

challenging – adj. difficult in a way that is usually interesting or enjoyable

marine – adj. of or relating to the sea or the plants and animals that live in the sea

ecosystem – n. everything that exists in a particular environment

tourism – n. the business of visiting places for pleasure

resident – n. someone who lives in a particular place

core – adj. of central importance

go down the toilet – expression to lose something or waste something