On May 14th, within a quarter mile off the west side of San Juan Island just down from Lime Kiln Pt. State Park, I was watching some Dall's porpoise (black with white dorsal fins). There was a group of them who appeared to be feeding. Up ahead of them and off a bit I noticed a very white porpoise. I was assuming it was a Dall's hybrid and it just happened to be very white instead of the sliver color they usually are. - Evidently not!
That afternoon I was talking to a friend and mentioned the white porpoise. She had seen one just four days before in an area maybe a dozen miles to the north. It was then that I learned that evidently not only do harbor porpoise males breed with Dall's porpoise females (known) but that Dall's porpoise males breed with harbor porpoise females (need more info to verify).
These two images are not very good. Click to enlarge them.
This image you can see the white body and the black dorsal fin and next to it a harbor porpoise of the normal coloration is off to the left.
This next image, shows the normal coloration harbor porpoise better (grey) and the white hybrid (?) as it is diving.
I'll be looking for this animal again or others like it. Fascinating. I would like to know more.
The other unusual encounter was with Steller sea lions on Saturday afternoon. When they are in here they are pretty docile, when I have seen them. Today however, their behavior was different. Whether they were just having a bad couple of minutes or they were adjusting for their seasonal departure I don't know. They are usually gone by the end of May.