Wyvern Milk is used to feed and tame baby Wyverns in Ark Valguero. This item requires you to steal from a wild female Wyvern or kill an Alpha Wyvern of either sex. Once you collect the milk ...

but killing an alpha would give you 50 milk bottles. Make sure your trap doesn’t face the Wyvern Trench. Once the trap is set, use Argentavis as your tame and head to the Wyvern Trench.