THE RIVER THAT WOLVES MOVED

A case study in how adding or removing a single species can affect whole ecosystems.

Presenting her account three ways—in cumulative lines modeled on “The House That Jack Built,” notes in smaller type accompanying each stanza, and then a prose recap—Carson explains how wolves, formerly hunted to extinction, were reintroduced to Yellowstone in 1995 to cut down on the elk population, which had overgrazed the willows that stabilized certain riverbanks. More riverside foliage brought more birds and insects; less erosion cleared up the water, which encouraged wildlife like beavers and trout and also, as the title suggests, changed the very shapes of the rivers’ courses. Hohn tucks two tan-skinned hikers, one a fascinated child and the other an elder in a wide-brimmed naturalist’s hat, into broad riverine landscapes and depicts them observing the naturalistically painted and posed wolves, elk, beavers, and other wild creatures they encounter on a day’s walk. This is definitely an ecological success story, but steer readers who would like it in greater detail rather than rehashed in three different writing styles—which ends up feeling somewhat redundant—to Jude Isabella’s Bringing Back the Wolves (2020), illustrated by Kim Smith, which covers the same trophic cascade. (This book was reviewed digitally.)

Eye-opening but sketchy and repetitive.