Hetty, we might be worrying unnecessarily.
Looking at the structure of the sculpture, the weight of it is pretty well in its base. The way it's sculpted, with the opening as I see it in the middle, will mean that the winds will blow through it. There isn't enough solid area of the serpentine to block the force of the wind and take the brunt of that force, which is what would blow it over.
I'm not sure about hurricane force winds, but just looking at it with its open middle and its heavy base, I'm thinking it might stand alone fairly well. Most of the time sculptors consider this when creating a carved piece. The rhythm of the design might take the force of the wind and disperse it. However, it does have to be set upon something solid that won't shift and move. Sand would shift and move. A thick heavy base might help prevent that movement, with lengths of rebar through the base and deep into the ground on which it sits. If the base doesn't shift, then the 'glued' piece of serpentine should not shift either.
I'm not a physicist, but I know about sculpting and the way the wind breaks its force when it can't get through something. If the base is heavy enough, it will hold itself up.
Something to think about.
