Orcas who are not compatible are forced to live in tight quarters together. The
resulting anxiety and tension cause fights between orcas. In the wild, orcas have
strong social bonds that may last for life, their social rules prohibit serious
violence against each other, and when fights do occur, they can find space to flee.
In captivity, there’s nowhere for them to go, which leads to injuries and death.
Article source: PETA Action Alerts