But it’s unclear why they left the island in the first place.
“I think if I could answer that question, I would be famous,” says Phillip Perry, Alaska Dept. of Fish and Game Area Management Biologist for Unit 18.
Perry says musk oxen don’t migrate seasonally. He says biologists know from other tagging projects in the state that they tend to just mill around.
“It’s not like they move long distances in a day or two,” Perry says. “They just kind of move around, a couple of miles here, couple miles there. And you add that up, over the course of year, and actually they can move some pretty good distances just with those small daily movements.”
The herd near Bethel could have been in search for food, but Perry says musk ox are very efficient eaters and have many options when it comes to food.
“They’re a real generalist,” says Perry. “They eat a lot of the small shrubs. They like dwarf willow, dwarf birch, blueberry bushes, that sort of stuff. But they also eat a lot of grass, both the sedges out on the tundra and then just grass.”
That includes dead grass in the winter time that Perry likens to eating “paper”. He says they can pull proteins and carbohydrates out of it.
“They’re able to extract more nutrition out of really poor forage than basically anything else,” Perry says.
Musk ox sightings near Bethel have been sporadic and often include only one or two animals being seen at a time.
Perry says single musk ox are almost always bulls as they will sometimes wonder far from where other groups are congregating. Perry didn’t see the herd that was on the Kuskokwim River last week, but just from the pictures he says can tell that it was a mixed herd.
“When you see groups, especially the size of this one, you know, it’s a real kind of family group,” Perry says. “It’s got a couple of bulls in it a lot of times, some cows, and some younger animals, and some calves.”
Perry says the musk ox population in the Y-K Delta is growing. The Alaska Department of Fish and Game is seeking funding for a tagging project with the hopes of one day being able to hold a small limited hunt.
“I’m expecting in the next 5 or 10 years, that it’s more common to see musk ox out here because we have the highest numbers we’ve ever had on Nelson Island,” Perry says. “And as we have more out there, I’m assuming that more and more groups like this will move off the island and move around.”