Islands like ice bergs

Jenny walks along the perimeter of the new little island.

When I was here sometime in the early nineties the island stretched
long and narrow.

A visit in the mid nineties found the island breached in the middle,
with a sand bar and two sandy beaches reaching out to each other
across the widening gulf.

Today's visit finds three islands, with no trace of the connecting
sand bar, and just a few small sand beaches.

Do islands calve like ice bergs?