[1] "Typically, when a fresh whale specimen is collected, preparators will attempt to remove as much of this oil as possible. But even then, they cannot get all of it out of the bones."
[2] “The marrow is oily and the oil is a source of energy for these animals. Especially the baleen whales, who typically have a period of the year where they don’t feed,” Robert Rocha, the New Bedford Whaling Museum’s Associate Curator of Science and Research, tells Popular Science. “There’s energy stored in the muscles and in the blubber, but the energy stored in the oil and the bones is a reserve energy source for them.”
[3] "Their bones contain a lot of oil. In life this substance is critical for the animals to maintain buoyancy in water and was the reason why so many were slaughtered during the eighteenth and nineteenth centuries. But it can cause major issues when trying to preserve their remains in collections."
[1] https://www.nhm.ac.uk/discover/whale-oil-and-half-an-inch-of...
[2] https://www.popsci.com/science/blue-whale-leaking-oil/
[3] https://www.nhm.ac.uk/discover/whale-oil-and-half-an-inch-of...