but natalia botero—acosta has spent more than a decade studying humpback whales. i saw it swimming — it was like lifting a pec. her work stretches from the tropical waters of colombia, where the whales breed, to the end of their 8,000km migration, antarctica. how is working in antarctica for somebody from the tropics? it's fascinating but i do get cold — a lot! 0h! when we spot a whale, natalia reaches for a surprising piece of scientific equipment. tell me about the crossbow. is that — is that a weapon? no, it's not a weapon, by any means. it's a tool. it's a scientific tool. we use them to collect, you know, blubber and skin samples. it goes with this bolt — modified, too. at the very end of this, we screw a tip — maybe 3cm tip — and then, inside is, like, three barbs that hold the tissue. but this — this barrier sort of like prevents the bolt from going inside further and then bounces back into the water. and this is how you get a tissue biopsy from a wild humpback whale. the tube on the end of the arrow takes just a tiny nick out of the animal's body. the samp