you are confusing legislation with regulation
there are regulations rising from the endangered species act that must be eliminated in order to obtain a new regulation.
The president can act on regulation but congress must act on existing law
Regulation has the full force of law after it is entered in the Federal Register for 30 days....
Both Criminal and Civil Penalities fully apply....
You can have a fully armormed SWAT team kick down your door and either take your life or arrest you and haul you off to jail.....
If Congress passes it or lets the agencies write it.....
Whats the difference to us the Citizens?