The term 'quickly increases' can be represented by the crossword solution GOOSES, which is a six-letter word. GOOSES is a plural form of the word goose, which is a type of waterfowl that is found in many parts of the world. The population of geese has been increasing rapidly in recent years due to a variety of factors, such as an increase in available food sources and a decrease in natural predators. As a result, the population of geese has been quickly increasing in many areas.