John,
These are "trap" nets and they are designed to lead fish into an area where they contained and remain alive. They lift these nets each day and they release the undersized or non-targeted species. It IS one of the cleaner ways to catch fish...not as clean as commercial hook and line...but I have always had a personal problem with the way they set up the "lead" net; this is the net that is anchored to the wall and runs perpendicular to the wall, or in the case of the Narragansett nets, perpendicular to the shore.
The mesh size, in my opinion, is too small and it allows for a fair amount of waste; keep in mind that they don't lift the net very often...if it's in the mesh...it's food for the crabs.
Several years ago I talked with the head of DEM about this situation and I was assured that this wasn't a problem...judge for yourself:
The Atlantic sturgeon is an endangered species:
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