Between 1960 and 1970, ivory poachers in the African nation of Zinbaku killed over 6,500 elephants. During that period, the total elephant population in Zinbaku fell from about 35,000 to just under 30,000. In 1970, new anti-poaching measures were implemented in Zinbaku, and between 1970 and 1980 over 800 poachers were arrested and expelled from the country. Nevertheless, by 1980, the elephant population in Zinbaku had fallen to about 21,000. Which of the following, if true, would best help to explain the apparent paradox presented above?
The poachers arrested in Zinbaku between 1970 and 1980 were rarely sentenced to long prison terms
Because of highly publicized campaigns against the slaughter of elephants, demand for ivory fell between 1970 and 1980
The elephant population in neighbouring Mombasa rose slightly between 1970 and 1980
In Zinbaku, between 1970 and 1980, thousands of acres of forest, the elephant's natural habitat, were cleared for farming