Why were blue and fin whales once considered too difficult for whalers to catch?

Blue and fin whales were historically considered too difficult to hunt because they were significantly faster and heavier than the "right" whales that whalers initially targeted. While right whales were slow-moving and floated after death, rorquals like the blue and fin whale could reach speeds of 30–50 km (20–30 miles) per hour and would sink once killed, making them nearly impossible to capture with traditional methods.12

It was not until the late 19th century that technological advancements enabled the exploitation of these species. The development of steam-powered whale catchers and the invention of the harpoon cannon—which utilized time-delay grenades—allowed whalers to overcome the whales' speed and defensive capabilities. Furthermore, innovations such as inflating carcasses with compressed air solved the problem of the animals sinking, ultimately turning these previously elusive species into primary targets for the whaling industry.21