What are Moonbird NFTs?

Moonbirds is the new big NFT trend hitting OpenSea.  I have not logged into the Moonbird website using Web3 quite yet to see how it actually works so this is just from my research.  It looks like Moonbirds were a particularly epensive NFT to mint and even at a high Eth price, it still sold out in a couple of days.  One of the special features of the Moonbird ecosystem is that you can stake your NFT on the Moonbird website which they refer to as nesting.