Food labels are essential for consumers to know nutritional content and where the food comes from. Tuna cans, for example, are marked "dolphin-safe" to ensure that the fish are harvested safely without injuring any dolphins.
According to NOAA Fisheries, dolphins and yellowfin tuna travel together for some unknown ecological reason, resulting in some dolphins becoming collateral damage during tuna harvesting. This dolphin/tuna connection was first noticed about 70 years ago when fishermen used dolphins' locations to find tuna.
The "dolphin-safe" label denotes that it "shows compliance with U.S. laws and regulations of tuna fishing operations." The Spruce Eats states that "earning the dolphin-safe label requires allowing an independent observer on each fishing vessel to confirm that dolphins are not viewed, chased, encircled, killed, or seriously injured during the tuna harvest."
In 2019, however, reports of three big-name American brands fraudulently labeling tuna cans as dolphin-safe emerged. A documentary called "Seaspiracy" specifically referenced a situation where a fishing company connected to one of these brands "killed 45 dolphins to catch just 8 tuna."
Since the documentary's release, there has been a marked improvement within the canned tuna industry. Sierra Club furthermore recommends checking Greenpeace's lists of the 20 most dolphin-safe brands before heading out to the grocery store to buy a can of tuna.