It's not a genocide, it's basically getting rid of something equivalent to dire wolves.

Paris was once besieged by hundreds of wolves in one of the single most metal events in all of human history (and why hasn't Powerwolf made a song about it)? A wolf pack, over 100 strong, besieged Paris every night being led by some kind of Dire Wolf (like, a very large alpha male), that would roam the walls and eat anyone around they could find. They'd even break into houses to kill people.

Then one night, the city guards had a trap where they would lure the wolves into the city, and the entire city guard would attempt to ambush them. The wolves, and their Dire Wolf alpha were cautious, but eventually many of them did enter the city. The ambush was sprung, the city gates slammed shut, and a completely fucking insane wolf-guard-battle took place.

All the wolves that were trapped inside the city gates were killed, including the Dire Wolf, and even with armor, swords, shields, and axes, the guards took something like 30 dead, killing around 100 wolves.

Anyways, ... the point is that when dealing with an enemy species; it is going to be a fight for life, because you die if you lose, and they are not operating on any kind of moral or ideological framework. We don't kill wild wolves like we used to because we see ourselves as caretakers of the earth, and allow them to live in the little corners of the world we set aside for them. But that is an act of mercy on our part. Not an act of equality. They would kill us and have no sense of such mercy, that's we're better than them.