Above: Extreme fly tipping! All that effort to dump tyres out on the island! Well, at least that is what it looked like to two passers by who were watching with their binoculars (or were they taking photographs?)!
Here is what we actually did ... (patented by Mark Thomas!)
Above: Back on the island Mark had a use for the tyres. 1st, you dig a round hole.
Above: A back seat driver!
Above: Place the tyre in the ground (no need to bury it) and use the turf to partially fill the tyre and weigh it
Above: Partially fill the tyre with gravel. Once finished, it should be about half full.
The reason for doing this is to create a nesting ground for Terns (in this case the common variety). The tyre is part buried to soften, or even hide them from view. The advantage this method has is that baby common terns can hide from predators under the lip of the tyre (which can be left in tact or cut away a bit).