Monkey Island

The little island in the River Leven is known as Monkey Island.

I had no idea why until I consulted the oracle that is Google and found this:

The name of the island in the River Leven at Balloch, close to Balloch Bridge. In early maps the island appears simply as Balloch Isle, and it is not until the late 19th century that there are any references to Monkey Island. There is no absolutely accurate basis for the name, but the most popular version is that a retired seaman - make him a captain if you want - lived on a hut on the island, and he had brought home a monkey with him from his travels, hence Monkey Island. That’s got a nice authentic feel-good factor to it, and is probably quite close to the truth – except for him having a pet monkey, which does diminish the story a wee bit. However, it is true that a succession of people lived in a succession of huts on the Island from the late 19th century onwards, and these huts are probably the basis of the name.
As the children of Haldane Primary School pointed out a number of years ago, the term “Monkey” is another name for the uppermost part of a ship’s bridge, and it often resembles the deck cabin of an old wooden sailing ship. In fact on some of the older Clyde steamers it probably was a recycled deck cabin. There has been a number of very fine wooden deck cabins used as dry-land “house-boats” in the Balloch boat-yards over the years. In fact, John Sweeney has an excellent example of one in his west-bank yard which he uses as an office. It seems most probable that one of the first of these old wooden deck cabins to come to Balloch was used as an early hut on the Island for a time and the Island got its name from that.
Source: http://www.valeofleven.org.uk/scottishplacenames/Mvale_names2.html