Scientists thought fish saved energy by swimming in flat diamond shapes, but study shows they actually prefer swimming in 3D ...

For 50 years, scientists believed that schools of fish would save the most energy by swimming in flat diamond formations.

Fish ladders are effective at allowing fish to swim upstream of low-head or shorter dams on the Columbia River. John Day’s ladder is 1,080 feet long. (U.S. Army photo by Karim Delgado) ...

Lansing's Brenke Fish Ladder transforming into amphitheater with $3.4 million investment ahead of Dam Jam Festival ...

The ladder is a series of tiered concrete walls, spanning about 800 feet along the side of the dam, that fish can use to go upstream. The troublesome part of the ladder, at least for the lamprey ...

In the spring, the ladder will facilitate the migration of sea-run fish for the first time since the dams were built nearly 300 years ago. Chance Viles / American Journal ...