In a world similar to ours, a mad scientist is bent on preventing the ascendance of one certain individual over the rest of the people inhabiting the northern part of the continental America, also called U.N.A. (the Unity of Northern America). The U.N.A. hold presidential elections similar to those of the earth USA and are currently in the final phase of their elections.
Our scientist has tried everything from social media, over press publications over appealing to the common sense of people, but he failed nonetheless. In a last resort he gathers the funds to transport 30'000 members of the species of the Rhinocerotidae to the southern border of the U.N.A. hoping to be able to disrupt the election process and stop people from committing, what he deems to be, a mistake of global consequence.
The scientist gathers all the Rhinocerotidae in the eastern part of Europe and wants to transport them all as silent/stealthy as possible to the southern border of the U.N.A. using Soviet Era transport planes.
How would he have to go about it and how many planes would he require?