He guided birding trips into the southern Negev desert, showing many observers locally breeding Hume's tawny owl and Nubian nightjar among other little-watched species of the area.
Hadoram's main sphere of interest was the complex geographical variation shown by birds breeding in and migrating through the Middle East.
He published The Complete Guide to Antarctic Wildlife, and commenced a 10-year project to produce the Photographic Handbook of Birds of the World.
Shirihai has visited almost every subantarctic island and the breeding grounds of all forms of albatrosses, with special interest in plumage variation and identification.
In 2008, he confirmed the continuing existence of the mysterious Beck's petrel (Pseudobulweria becki), known until then from 2 specimens collected in the 1920s and a handful of tentative sight records.