Silence Unleashed

I really enjoy the concept of this poem -- that moment between wake and sleep is always the most fertile, and often the most disturbing.  A couple of lines in this don't really work for me, particularly "quietly it whispers" -- this seems doubly redundant, as whispers are by nature quiet, and also you're talking about silence.  I would actually suggest you use some adjective relating to its insidious nature rather than quiet, to strengthen that notion. Additionally,  "finally sleep takes root" seems a little awkward. I tend to think you could do without "finally", perhaps just "as sleep takes root", although the actual taking root idea is kind of out of the blue.  I'd suggest trying a hunting/striking image there, to work in with the silence-as-raptor motif.  Perhaps sleep could be a stealthy fox or something, coming in to steal away silence's prey?  Just throwing around ideas now.  All things considered, the format of the poem is quite good and the idea is definitely there, so just a little more continuity to develop it and you've got a really good poem.