The Japanese fishing industry labels dolphins as "pests" and conducts a mass slaughter each year to keep down the dolphin numbers so that competition for fish such as bluefin tuna is reduced.
Dolphins are rounded up in underwater pens, deliberately disoriented by the excruciating noise of metal poles being struck beneath the water (especially painful and cofusing for echolocators like dolphins), then hoisted from the water by their tails--still living--and dropped onto truck beds or tied to bumpers and dragged to slaughter areas where they are mortally wounded by machete and allowed to flop and bleed on the concrete floor until dead.
The dolphins are then cut up, packaged, and sold to grocery stores in Japan. This needless, brutal slaughter happens by the tens of thousands every year. Please sign a petition to stop this practice here.
I would also encourage you to watch the accompanying YouTube video of the slaughter. It is terrible, but it is important that we fully grasp the scope and brutality of this slaughter.