Who let this kid run around naked in the forest?

I liked that Wordsworth started off "The Prelude" with himself as a little boy trekking through the woods and bathing naked in the stream.  It gives a child like wonder to the wilderness he is talking about in the first stanza.  He calls himself a "savage" which I thought was an interesting choice of word.  I don't think he meant it in a negative way.  I see it as more of a destructive child, like the child in Charlotte Smith's glow worm poem.  However, he was just trampling through the woods on his own without anyone else around.  This makes it seem like as a young boy he was running around taking what he felt like from nature without appreciating nature itself.