The Skagit Valley Herald (subscription required) had an article Sunday about a USGS project to map the ocean floor of Skagit Bay and Deception Pass to show how the seabed looks today and how it looked 150 years ago.

For the scientists with the Skagit River System Cooperative, an agency of the Sauk-Suiattle and Swinomish Indian tribes that works to improve the fisheries in the river basin, the maps of before and after may help them prove a theory.

Confining the river to two channels causes silt-laden fresh water to squirt like a “fire hose” into the Skagit Bay, said Greg Hood, senior restoration ecologist for the tribal cooperative.

Scientists theorize that the river silt may have buried eelgrass beds, which are important for juvenile salmon and Dungeness crab, he said.

“What they are doing right now is basic science,” Hood said. “At some point, that will be used for restoration projects.”

Many restoration efforts are aimed at restoring lands that were historically tidal marsh to their natural state, Hood said.