And in Zimbabwe, 34 poachers died in 1990 in the search for the black rhino. Recently, conservationists met to (3)___________a campaign to persuade countries where rhino horn is still part of the traditional medicine to switch to substitutes. The biggest threat to the survival of the rhinoceros is the refusal of certain countries to enforce a ban on domestic trading in rhino horn. The rhino horn is included in many doses for disorders raging from fevers to nosebleeds.