Alaska Department of Fish and Game
When this rainbow trout was opened up, scientists at the Togiak National Wildlife Refuge in Alaska were astonished to find 20 shrews.

Gluttonous Rainbow Trout Gobbles Up Its Weight in Shrews


The trout was only 19 inches long, but it managed to cram no fewer than 20 shrews into its belly.

Researchers in Alaska were startled to discover the shrews in this tiny fish’s stomach, especially since shrews are land animals, while fish …. Well you know. Unless you’re these catfish, which have learned to squirm onto land to grab prey.

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Shrews are not rodents, but they are mouse-sized. How they got into the trout’s tummy was something of a mystery.

But get there they did, and researchers in the Togiak National Wildlife Refuge in Alaska found them when they opened up the rainbow trout. The scientists surmised that the trout must have nabbed the shrews in floodwaters or some such.

It is not uncommon for rainbow trout and their fish relatives to eat shrews, rodents and other small mammals, and freshwater fish are known as opportunistic predators that are not very picky eaters, said Mark Lisac, a fish biologist the wildlife refuge, to In addition, trout are among the animals that stock up for the winter, eating more than usual. The two factors combined in a voluminous, if not terribly delicious, meal. 

"My best guess is that the shrews were on an island [or river bank] that flooded,” Lisac said, “and the rainbow happened to be in the right spot at the right time.”