Residents of Nome in Western Alaska had a bit of excitement earlier this week as the drama of nature played out offshore in the waters of Norton Sound, with a pod of marine-mammal-eating killer whales on the hunt for an adult gray whale and calf.

National Park Service employees with the Bering Land Bridge National Preserve, which has its headquarters in Nome, caught some of the drama on camera, posting pictures and video to the park's Facebook page Thursday. The activity caused a hubbub in the community of about 3,750 located on the Seward Peninsula, with residents turning out to watch the hunt from the shore. Though both orcas and gray whales frequent Norton Sound in the summer, it's unusual for them to come so close to shore, said Gay Sheffield, who works with the University of Alaska's Marine Advisory Program in Nome.

She said that the gray whale's decision to move closer to shore, into the shallows and the high surf, bolstered that day by wind, was a wise defensive strategy.

"I think everybody's doing a risk assessment," Sheffield said of the whales and their movement closer to shore. "If you're a killer whale, you wonder, 'is it worth potentially stranding to get closer?'"

And in this case, it seems to have paid off. The aggressive orcas retreated, apparently deciding the prize wasn't worth the risk -- at least for the time being -- and both mother and baby were able to return to deeper waters. It wasn't just the baby that had been at risk though, Sheffield noted. Killer whales fall into two camps -- "resident" whales, which tend to eat fish, stay in one spot and have larger extended families, and "transient" whales, which prefer marine mammals as the bulk of their diet and can be impressive predators.

"These are animals that are more like a pack of wolves," Sheffield said of that latter group of orcas. "They typically have smaller numbers, and they're transient, so they don't stick around in one place for long."

And like a hungry pack of wolves chasing down a moose, killer whales have been known to collectively take down prey much larger than any one individual in the pod.

Contact Ben Anderson at ben(at)