Scene on the Sound: Bell M. Shimada spends this gray day working off the Shoreline coast

Bell M. Shimada works Puget Sound off Shoreline
Photo by Jan Hansen

Bell M. Shimada conducts both acoustic and trawl surveys. For acoustic surveys, the ship uses a multibeam echo sounder (MBES) that projects a fan-shaped beam of sound that bounces back to the ship. The ship’s MBES, one of only three systems of its type worldwide, acquires data from both the water column and the sea floor. Scientists can detect fish as the ship passes over them, measuring the signal reflected by the fish to estimate their size and numbers. The system can also map and characterize the sea floor.

The ship conducts trawl sampling with a standardized, three-bridle, four-seam bottom survey net equipped with a rock-hopper sweep. The trawls sample the biomass of fish in a given survey area. This helps scientists learn what species are in observed fish schools and gather other biological data.

The ship’s wet lab allows scientists to sort, weigh, measure and examine fish. The data is entered directly into the ship’s scientific computer network. Bell M. Shimada’s marine mammal and bird observation stations are equipped with sensors to aid researchers in identifying and tracking protected species.

--Information from NOAA's Office of Maritime and Aviation Information