Why does Thoreau first visit the Maine woods as noted in the biography, Thoreau of Walden Pond?

Throeau initially visits the Maine woods in the hopes of seeing large north American mammals such as moose, cougar panther, lynx, wolverine, wolf, bear, deer and beaver which are still plentiful in these woods. The terrain is rocky and mountainous, but a great variety of berries and medicinal plants cling to the land. Eagles and other predatory birds make their nests in pine forests and hunt for their dinner in streams burgeoning with fish.