Um, that's a bit of a puzzle, the whale breathes in air at atmospheric pressure, therefore to a first order approximation the air in its body can't be at much more than that after compression and then surfacing.
I'm not saying its impossible, but I can't see what pressure is driving the nitrogen deep into joints etc, it should all be in equilibrium.
the whole point with bends and SCUBA is that you are breathing high pressure air, and so high pressure nitrogen diffuses into the parts of the body with lower partial pressures of nitrogen, then when you surface the high pressure nitrogen wants to diffuse out again, but can't easily. If the whole lot starts in equilibrium then it all compresses together. This loosely is why duck diving into quite significant depths is safe without a decompression stage.