LOS ANGELES TIMES: Catching swordfish off the coast of California today means leaving milelong mesh nets deep in the ocean overnight. But what fishermen pull up is mostly not swordfish. For every one of the hefty, long-billed swordfish in a net, it’s estimated that there are four other marine animals entangled there.
The particular kind of drift “gillnets” used by swordfishermen have holes sized to ensnare swordfish (by their gills, hence the name). But the nets also capture dolphins, whales, sharks, sea turtles and numerous other species of fish. At least half of this “bycatch” is tossed back out to sea — in the case of dolphins, sometimes without their fins (which get tangled in the nets), leaving them no chance of surviving. Most of the mammals trapped in the nets are already dead or dying by the time the nets are raised, having spent hours thrashing underwater. But the marketable fish that are trapped by happenstance are hauled in and sold.