Can Orcas keep pets?

We often observe fur seals or Dall's porpoises following groups of fish-eating orcas. But this group we saw some days ago had an unusual companion. A single Pacific white-sided dolphin was travelling with the orcas, as a normal group member, for at least 1.5 hours. At first we mistakenly thought he was a strangely coloured calf. This is amazing to us not only because of this weird companionship, but also because Pacific white-sided dolphins are rarely seen in this area. We have never observed them before in the nearshore waters of the Commander Islands. Perhaps this dolphin was travelling with orcas for a while and then followed them to our research area from offshore or more southern waters where this species is more common. The more you look closely at nature, the stranger it becomes.

Source: RussianOrca.org