The earliest recorded sighting of North Island occurred in May 1840, during the third survey voyage of HMS Beagle, commanded by John Clements Wickham.

It was sighted from the peak of Flag Hill on East Wallabi Island in early May, explored on 22 May, and given its name due to "its relative position to the remainder of Houtman's Abrolhos".

It was surrounded by a range of hills, with a flat in the centre, covered with coarse grass, where a great many quails were flushed, affording good sport, but not a single wallaby.

In 1959, a group from the University of Western Australia's Department of Zoology, accompanied by the English botanist Mary Gillham, travelled to the island; a brief article on its physiography, vegetation and vertebrate fauna was published the following year by Glen Storr.

[5] More recent visitors have included P. R. Howden in 1974, Robert Ivan Taylor Prince in 1976, Ronald Eric Johnstone in 1981 and 1983,[9] Phillip Fuller in 1992,[10] and Judith Harvey and Vanda Longman in 1999.

Based on the data for North Island, the Houtman Abrolhos has been described as having a Semi-arid climate with warm, dry summers and cooler, wet winters.

During summer a high-pressure ridge lies to the south, causing persistent winds from the southeast or southwest at speeds exceeding 17 kn (31 km/h) almost half the time.

A tropical cyclone occurs in the area about once in three years, between January and April; these may generate extremely high wind speeds that are potentially destructive.

Stable dunes are vegetated by Atriplex paludosa (marsh saltbush), Scaevola crassifolia (thick-leaved fan-flower), Olearia axillaris (coastal daisy-bush), Myoporum insulare (blueberry tree) and Exocarpos sparteus (broom ballart).

Sheltered areas behind dunes support Salsola kali and Myoporum insulare and also Nitraria billardierei (nitre bush), the last of these being the only plant on the island to grow over 1+1⁄2 m (5 ft) high.

In areas where limestone is close to the surface, the vegetation consists of Pimelea microcephala (shrubby rice-flower), Spyridium globulosum (basket bush) and Acanthocarpus preissii.

[5] The rim of the central plain is vegetated by a dense shrubland of Rhagodia baccata (berry saltbush), Atriplex paludosa and Threlkeldia diffusa (coast bonefruit).

The most low-lying area of the central plain, south of the salt lake, is water-logged in winter; it is vegetated by a dense mat of Sarcocornia quinqueflora (beaded samphire), Sporobolus virginicus (marine couch) and Suaeda australis (seablite).

[5] The dune, limestone and salt lake vegetation communities on North Island are considered to have high conservation significance.

Stokes explicitly stated the tammar wallaby to be absent from North Island in 1840,[2] and it was not recorded by the Percy Sladen Trust Expedition in 1913.

Possible reasons for this success include the absence of the wallabies' natural predator, the carpet python (Morelia spilota imbricata);[24] the availability of additional food and water from the fishers' huts, which are occupied during the harshest time of the year; and the presence of the air strip, which apparently provides additional food for them.

CALM staff visited the island in April and May of that year and produced a report recommending an investigation into controlling population levels by the use of implanted contraceptives.

[23] Eight European rabbits (Oryctolagus cuniculus) were introduced in 1934, and were found to be "exceedingly numerous" by 1945, but by 1960 they were extinct, apparently from predation by feral cats.

[23] Reptiles recorded on North Island include Binoe's prickly gecko (Heteronotia binoei), the gecko Christinus marmoratus, the Jew lizard (Pogona barbata), King's skink (Egernia kingii), the western limestone ctenotus (Ctenotus australis), the western worm lerista (Lerista praepedita),[5] the common dwarf skink (Menetia greyii),[27] and the Abrolhos bearded dragon (Pogona minor minima).

[5] The birds most often mentioned in relation to North Island are the Abrolhos painted buttonquail (Turnix varius scintillans), a rare subspecies of the widespread painted buttonquail (Turnix varius) known only from the Wallabi Group and protected under the Wildlife Conservation Act 1950; and the brush bronzewing (Phaps elegans), one of the most common birds on North Island, the mainland populations of which are decreasing.

Birds commonly recorded as resident on the island but not recorded as breeding there include the Pacific reef heron (Egretta sacra), white-bellied sea eagle (Haliaeetus leucogaster), red-capped plover (Charadrius ruficapillus), fairy tern (Sterna nereis nereis), Australian pipit (Antus australis) and western silvereye (Zosterops lateralis chloronotus).

Other observed visitors include the great cormorant (Phalacrocorax carbo novaehollandiae), nankeen kestrel (Falco cenchroides cenchroides), banded lapwing (Vanellus tricolor), greater sand plover (Charadrius leschenaultii), whimbrel (Numenius phaeopus variegatus), greenshank (Tringa nebularia), sanderling (Calidris alba), willie wagtail (Rhipidura leucophrys leucophrys) and brown songlark (Cincloramphus cruralis).

[32] North Island is considered to have high conservation value with respect to its populations of brush bronzewing and Abrolhos painted buttonquail, and its dune, limestone and salt lake vegetation communities.

The potential existence of historically significant artefacts on Record Hill, namely the bottle left by Wickham and Stokes in 1840, has not been assessed.

However, all of the island's limited anchorage and jetty space is occupied by commercial fishers, so landings from private or charter boats are possible only by prior arrangement.