Only if you define vegan as to strictly avoid any animal product (and define humans as animals). A somewhat looser Definition says to avoid animal exploitation.

So a product made by a non-domesticised animal in a natural way - e.g. Penguin guano - could be seen as vegan. The animal produces it anyway and the product isn’t won through keeping the animal captive and / or “stealing” from it.

After all I wouldn’t be too strict with definitions here.