Of course the question of comparison comes to mind. Does this sound similar to baby foxes? Here is a site I found with several audio clips of various fox calls. Here's one that's described as having a human sounding voice at the end, and it does sound close to what's on the Umatilla tape.
Who can say. I'm no expert on fox or cougar sounds. It's possible that people in the area know what foxes and other animals of the region sound like, and wouldn't be so quick to jump to the Bigfoot connection.
It could be Bigfoot, it could be shape shifting entities, it could be fox season.
PENDLETON -- Baby foxes or Bigfoot?
The eerie late-night serenades began in November and emanate from a brushy swamp on the Umatilla Indian Reservation east of Pendleton. The cries range from high-pitched screams to basso profundo roars.
"It's causing an uproar around here," said Sylvia Minthorn, who lives in a tribal housing unit near the swamp, where she used to play as a child.
She's seen grown men's hair stand on end when the shrieks commence.
Colleen Chance, a tribal housing authority employee, keeps a recording of the howls on her iPhone.
"It's kind of spooky," she said. "Some say it's foxes, some say it's a female coyote and some say it's Sasquatch. I don't know what it is."