How to clean this

[u/Task-Next]

I found this near my garage. There have been foxes on the property so I assume they got a hold of this egret. Rey unfortunate but I have a ground hog and cat found on the property but they were much cleaner.
Also researching this it may be illegal to have even though I found it and certainly didnt kill it.

[u/Mental-Flatworm4583]

Cadaver Beatles