In 2022, it was considered a defunct species by the IOC, due to its low genetic divergences and absence in morphological differences.

It possesses specialised physical characteristics and exhibits unique behaviour to assist in hunting and catching prey.

[4] Some authorities maintain a treatment of the "eastern osprey" population as one of four subspecies of Pandion haliaetus, the only extant species of the genus and family.

Some arrangements place it alongside the hawks and eagles in the family Accipitridae—which itself can be regarded as making up the bulk of the order Accipitriformes—or else allied with the Falconidae into Falconiformes.

The Sibley-Ahlquist taxonomy has placed it together with the other diurnal raptors in a greatly enlarged Ciconiiformes, but this results in an unnatural paraphyletic classification.

The throat is white, a black line extends from this through the eye to a dark patch around the ear, demarcating this from the pale colour at the head.

The juveniles resemble adults, although the iris colour is a darker orange-yellow and plumage is distinguishable in multiple and subtle ways.

[16] In flight, the eastern osprey has bowed wings with narrow primary feathers that are angled and separate, giving a fingered appearance to the observer below.

[14] Ospreys differ in several respects from other diurnal birds of prey, toes are of equal length, its tarsi are reticulate, and its talons are rounded, rather than grooved.

[16] The species is solitary or paired with a breeding partner, the association of several individuals in family groups are unusual records.

[16] Occasional records are given for other marine life—sea snakes, molluscs and crustaceans—and for terrestrial species of reptiles, insects, birds and mammals.

After seizing their target they use heavy wing beats to rise from the water's surface, resuming a regular action with the fish being carried head first toward the shore.

[25] Rocky outcrops just offshore are used in Rottnest Island off the coast of Western Australia, where there are 14 or so similar nesting sites of which five to seven are used in any one year.

The nest is a large heap of sticks, driftwood, turf or seaweed that is usually built in the fork of a dead tree or limb, cliff faces are also utilised.

[citation needed] Generally, eastern ospreys reach sexual maturity and begin breeding around the age of three to four years.

A nest examined in 1902 found fish skeletons at the edge and a seaside plant "pig-face" (Mesembryanthemum) in full growth.

[31] There is evidence for regional decline in the state, where former territories at locations in the Spencer Gulf and along the lower Murray River have been vacant for decades.

Nesting sites on the Eyre Peninsula and Kangaroo Island are vulnerable to unmanaged coastal recreation and encroaching urban development.

[20] As of 2024[update] there were estimated to be only 50 breeding pairs left in SA, mostly on islands and isolated stretches of coast, reflecting a 26 per cent population decrease over 10 years.

[31] The population had declined until around the 1970s, when they began to thrive in northern area of the state, and started expanding their range southwards.

In July 2023, there were 13 breeding pairs on the Central Coast of NSW, the highest number ever observed in the region, and they were second most common raptor there, after the White-breasted Sea Eagle.

[citation needed] A 1902 report by Alexander Milligan of a breeding pair in the southwest region was published in The Emu, and a description of a nest with two eggs located at Cape Mentelle which had been photographed eleven years earlier by A. J. Campbell.