It has sandy, calcarenite soils, is mainly vegetated with pasture grasses, and has some remnant patches of heathland and Melaleuca woodland.

Pearson Island, the second largest of the whole Investigator Group, and containing its highest point at 231 m above sea level, is vegetated with shrub and heathland with patches of Casuarina and Melaleuca woodland.

Lying 3 km south-south-west of the Veteran Isles is Dorothee Island, the most southerly of the Investigator Group.

[9][10] The Investigator Group Wilderness Protection Area comprises Ward Islands, Top Gallant Isles, Pearson Isles with exception of a portion of land on Pearson Island which is held by the Australian Maritime Safety Authority for "lighthouse purposes".

[12] The group was identified by BirdLife International as an Important Bird Area (IBA) known as the Investigator Islands (sic) Important Bird Area in 2009, because of its population of the vulnerable species, the fairy tern, as well as significant populations of Cape Barren geese, Pacific gull and black-faced cormorant.

[13] Other birds for which the IBA is significant include large numbers of breeding short-tailed shearwaters and white-faced storm-petrels.