One day at Teton Marsh

Sally Carrighar, One day at Teton Marsh, New York, Alfred A. Knopf, 1954, p. 94.

The Mink, out on the mud, makes a quick savage bite of a dragonfly nymph, a scud ram’s-horn and physa snails, caddisworms.
One caddis worm dragged a shelter he’d made by cementing together tiny living snails. The Mink’s teeth crushed the whole thing, unwilling guests and their host. And more and more dragonfly nymphs- they were the meaty prey. He had enjoyed them all summer, but recently they had disappeared.