No, off course not. It isn't even a channel.

Channels are made by mankind.

The, so called, English channel isn't.

If you still consider it a channel then it's length is just over 400 km. (from Sennen till Dover).

The Pangalanes-channel in Madagaskar is more than 500 km long.

This is not a very small island, it is bigger than France and the world's 4th biggest island. Some of the famous places include Nosy Be, the Tsingys of Namoroka reserve, the Berenty reserve (where some of the lemurs live).