(energetic music) - Hello, I'm Stephen Hegg in the Crosscut KCTS 9 newsroom.

Scientists are using a new technology to help Pacific Northwest waterways produce more salmon.

At the Lower Green River, researchers are injecting tiny radio sensors, the size of a grain of rice, into very small salmon about a month after they show up in the river.

Previous tracking devices required larger fish, and retrieving data from them is more difficult.

These tiny radio tags are paired with a large floating barge.

This one is attached by cable to a Southcenter Pedestrian Bridge.

The barge tracks fish passing underneath.

This sensor and barge technology is more efficient in telling scientists where and when young salmon go and about the habitat they need.

That increases knowledge about how to protect and rebuild habitat even in a highly developed urban waterway like the Green River.

Against all odds, the lower Green River is one of the major salmon producers for Puget Sound.

I'm Steven Hegg.

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