A survey carried out in 1982 by the responsible government agency used a helicopter to access the island’s summit.

[7] Haystack Island consists of a seam of Bridgewater Formation calcarenite that sits on a largely submerged ridge of Gleesons Landing Granite.

[9] A survey carried out in November 1982 found 11 species of plants making up a shrubland covering the island’s ridge including Grey Samphire, Marsh saltbush, and Nitre-bush in the deeper soils, and Cushion-bush, Round-leaved Pigface and Southern Sea-heath in the shallower soils.

Since 2007, it has been a prohibited area where access is only allowed by permit in order to protect the breeding population of seabirds.

[10][11][12] Since 2012, the waters surrounding its shores are part of a habitat protection zone located within the boundaries of the Southern Spencer Gulf Marine Park.