The English name, originally 'Sclavonian', is first attested by George Montagu in his 1802 Ornithological Dictionary,[7] from Sclavonia, an old name for northern Prussia, referring to the species' main breeding area in Europe;[8] the spelling was emended (without any reason given) to the current 'Slavonian' by Hartert in 1912.

[9] The horned grebe was formally described in 1758 by the Swedish naturalist Carl Linnaeus in the tenth edition of his Systema Naturae under the binomial name Colymbus auritus.

[11] The horned grebe is now one of the nine species placed in the genus Podiceps that was introduced in 1787 by the English naturalist John Latham.

The breeding plumage has bright erectable "horns", black fan-shaped cheek feathers and an overall red-and-black colour.

Juveniles appear similar to a non-breeding adult except they are a slightly duller shade of white and their back is tinged with brown.

[2] The chicks are fluffy, with a dull grey back, a white belly and distinct black-and-white facial and neck striping.

[4][15] A third subspecies P. a. arcticus Boie, 1822 has sometimes been accepted for the population in coastal Norway, Iceland, and Scotland,[5] but is now treated as synonymous with nominate P. a.

[4][16] Young begin calling for begging purposes in a slightly trilled peeping noise, similar to that of a domestic chick.

[17] The species breeds primarily in boreal and subarctic regions with a frost-free period of around 90 days or less,[4] but also in temperate zones, including prairies and parklands.

Following migration, they winter in marine environments, including off estuaries and bays or sandy beaches; in some places, for example in Norway, large numbers congregate on inland lakes.

[5] Horned grebes dive underwater using their large feet for agile manoeuvrability to feed on aquatic arthropods, fish and crustaceans.

Underwater they swallow or capture large prey and re-emerging at the surface to manipulate the fish headfirst.

[19] During the summer, aquatic and airborne arthropods are preferred, whereas winter selection favours fish and crustaceans.

They will eat their own feathers from a young age, so that their stomach has a matted plug that functions as a filter to hold fish bones until digestion.

This initial pair bonding ceremony is to ensure correct species identification, sex and compatibility.

[19][20] Horned grebes usually arrive at breeding grounds in pairs or solitarily to seek out a mate in the spring or early summer.

[16] This is due primarily to human disturbance, forestry operations around breeding sites, fluctuating water levels, and stocking of lakes with rainbow trout that compete for aquatic insects.