This motive exhibits elements of nature and hunting.  Hans Redlich also mentions that the motive indicates that danger has not yet passed.

Motive Labels
“Hunting Call”
“Jagdfanfare” or “Hunting Fanfare” – (Pfohl, p. 226)
“Horn Motive” – (Windsperger, p. 42)
“Hunting Horns” – (Redlich, p. 25)

Hunting Call – Order of occurrence by Act and Scene
Act II: Scene 1