Someone was very, very hungry!
Researchers conducting a trout study a few years ago in Alaska's Togiak National Wildlife Refuge reported the unusual discovery of a rainbow trout with close to 20 baby shrews (a small mammal) in its stomach. The find was so interesting, Togiak wrote about it on its Facebook page on Aug. 28, and the story became an instant hit.
Mark Lisac, a fish biologist at Togiak, told LiveScience that it is quite rare to find a fish with so many furry stomach occupants. And this fish wasn't even that big, measuring only 19 inches long.
Lisac called the meal "an awful lot for one fish to put down," per LiveScience.
The Nature Conservancy's Cool Green Science blog noted it's not unheard of for trout to eat small mammals. These fish seem to have a particular taste for voles, a type of rodent currently undergoing a population explosion. However, the blog notes also that shrews are not rodents.
"It would be interesting to look more into shrew ecology and see if there might be something else going on -- a high density of shrews, or some shrew habit that trout have learned to exploit," Cool Green Science's Matt Miller wrote.
Lisac has his own theories about the fish's feeding frenzy.
Opportunistic eaters, trout have been known to chow down on small mammals, especially in the summer when they load up on food before the sedentary winter months. "My best guess is that the shrews were on an island [or river bank] that flooded, and the rainbow happened to be in the right spot at the right time," Lisac told LiveScience.