Nearly 20 Shrews Found in Rainbow Trout's Stomach

Researchers in Alaska's Togiak National Wildlife Refuge received a shocked when they discovered 19 shrews lodged in the stomach of a small rainbow trout.

Less than 20 inches long, the fish clearly had an appetite that outweighed its size, according ot Mark Lisac, a fish biologist that works at the refuge.

That's "an awful lot for one fish to put down," Lisac told LiveScience.

The discovery puts the record (or, at least, the only record Lisac is aware of) of seven shrews found in a single fish's stomach to shame. Even stranger, the fish to hold the previous record was a grayling, which, according to Lisac, "keys in on shrews." Rainbows, on the other hand, are opportunistic eaters known to sample a wide range of prey.

As to how the shrews, a land-dwelling creature, came to find itself in a fish's stomach, Lisac says he has formed his own hypothesis, largely based on the fact that shrews are less than superb swimmers.

"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," he said.

Alaska Public Media cites Lisac as saying that many fly fishermen have taken to using a vole or shrew pattern to lure their catch.

"It's just a big wad of deer hair tied on a hook, and then it's trimmed to look like a mouse or a vole," he said. "And if the fish are there, they usually find it pretty irresistible."

Meanwhile, Lisac says the size of the meal can be blamed on the season. Fish feed heavily during the summer in order to prepare for the winter, at which point they take on a more sedentary lifestyle.