The island is an accumulation of biogenic sediment similar to Heron Island, and it has been sufficiently stable to accumulate vegetation. A major component of the mobile sands of Bushy Island is Foraminifera, a type of amoeboid protist.
Similar to Heron Island, the island is composed of biogenic sediment that has accumulated enough stability for plant growth. The mobile sands of Bushy Island contain a substantial amount of Foraminifera, a type of amoeboid protist.