no, it's not a weapon, it's a tool. that tool allows natalia to take whale tissue biopsies. a tube on the end of each arrow takes just a tiny nick... ..out of each animal's body. the sample is three centimetre, something like that, for an animal, you know 16 metres long. so it's essentially a mosquito bite. well, it clearly didn't bother them very much because they're hanging around the boat. analysing this tissue can reveal if a female humpback is pregnant. in years that we have low sea ice then the following year, you have lower pregnancy rates, and that's as good as it gets in, like, you know, getting to know the environment and getting to know the effects of all these conservation threats on the animals. this is what the whales and many other animals here feed on — antarctic krill. swarms of them thrive here because they eat algae that lives in sea ice. so researchers want to know if this crucial marine food supply is decreasing as rising