The resurgence even has a catchy moniker: the "humpback comeback." When I booked a whale watching tour from Port Angeles earlier this month, Island Adventures lead naturalist Erin Gless said I'd have a 92 percent chance of seeing these large whales.

Sure enough, after the Island Explorer 4 motored out into the Strait of Juan de Fuca, the onboard naturalist grabbed her microphone to announce, "Thar she blows! 10 o'clock, 10 o'clock."

Tour guests crowded the boat's rails and followed the directional pointer to see a humpback surface with a steamy exhalation, rest for a minute and then dive again. Then the captain spotted another. The vessel cruised onward and found yet another humpback, then several more and then a pair swimming together, provoking whoops of excitement from the observers.

"We definitely had whale soup out there today," marine naturalist Renee Beitzel said at the end of the day.

Humpbacks are a favorite of whale watchers because they make showy dives and sometimes jump out of the water or slap the surface with their long pectoral fins. Beitzel said if guests had booked this same tour six or seven years ago, they probably would not have seen any humpbacks.