The Monkey Head is in the clearing one map screen east of the river fork.

A fence is blocking your access to the Monkey Head, however.

Look closely at the fence.

There seems to be a gate.

To open the gate is a bit more tricky.

There must be some sort of secret handle.

Sniff out the solution.

The answer is right under your nose.

Or actually under the totem pole's.

Pull the rear totem pole's middle nose to open the gate.

Unfortunately, the gate slides shut after you let go.

You need something to hold down the lever while you go through the gate.

Herman Toothrot won't help you, but someone else can.

Pulling the lever seems to be pure monkey business.

So maybe a monkey would help you.

There is a monkey near the crack on the map screen including the south shore.

You need to make friends with the monkey.

How do I befriend a monkey?

Once the monkey is following you around (after you've fed it five bananas), lead it to the fence outside the Monkey Head.

It would hold down the nose for you...

If only it knew how.

Show the monkey all there is to nose-pulling.

Once more, pull the nose lever. The monkey will now dangle on it forever.