Raven Vocalisation

The Vocal Repertoire

[science] Bernd Heinrich, through years of observation of wild and captive ravens in Maine, documented at least 30 vocalisations with consistent contextual meanings. These include:

• The deep croak ("kronk" / "pruuk"): The most common call, used in flight and as a general contact call. Distinctive hollow, resonant quality; clearly distinguishable from the caws and kaah calls of crows at distance.
• Knocking calls: A wooden "toc-toc-toc" call used in alarm and territorial contexts.
• Bell-like calls: High, clear notes used in close-range interaction, often between pair members.
• Gurgling / water-like calls: Complex modulated sounds used in social contexts and apparent play.
• Alarm calls: High, sharp calls given in response to raptors and other threats.
• Recruitment calls: Calls apparently used to recruit other ravens to food sources — documented specifically in Heinrich's roost studies.¹

Vocal Learning and Dialects

[science] Ravens are oscine passerines ("songbirds" in the technical sense) and therefore have the neural architecture for vocal learning — the ability to modify vocalisations based on auditory experience. This distinguishes them from most birds, whose calls are largely innate.

As a result of vocal learning, raven populations develop regional dialects — geographic variation in call structure. Captive ravens raised in isolation from conspecifics develop abnormal vocalisations, confirming the learned component. Ravens raised with human contact acquire human words and other non-raven sounds.²

Dialects in ravens have been documented between populations at geographic distances of a few hundred kilometres in some studies. The functional significance of dialects — whether ravens use them to discriminate local from non-local conspecifics — is not fully established.

Mimicry

[science] Ravens mimic a wide range of non-raven sounds:

• Wolf howls: Heinrich observed ravens imitating wolf calls. He proposed this may serve to attract wolves to a carcass — wolves can open frozen or tough carcasses that ravens cannot access alone. This raven-wolf mutualism is well-documented in Yellowstone and Scandinavian wolf territory studies.¹
• Other corvid calls: Ravens mimic the calls of crows, jays, and other corvids.
• Raptor calls: Ravens occasionally produce hawk and eagle calls — the function is unclear but may serve to alarm conspecifics or manipulate other species.
• Human speech: Captive ravens with human contact reliably produce recognisable words. This is the same vocal learning mechanism applied to human vocalisations.
• Environmental sounds: Wind, water, tools, vehicles — captive ravens mimic sounds from their environment.

Calls in Social Context

[science] Raven calls are functionally differentiated — different call types are used in different social situations, and other ravens respond differentially to them. Research by Bugnyar's group has shown that ravens can discriminate between calls that signal threat and those that do not, and between calls from known and unknown individuals. The discrimination of individual identity from voice alone enables ravens to manage their complex social relationships without visual contact.³

Pairs maintain contact through duetting — the coordinated production of overlapping calls between pair members. Duetting appears to function in pair-bond maintenance and territory advertisement.

Vocalisations in Culture

[lore] The raven's remarkable vocal range has been noted across cultures. Odin's ravens Huginn and Muninn are described as "speaking" to Odin — a mythologisation of the real observation that ravens can produce sounds resembling speech. Edgar Allan Poe's choice of the raven as the creature that speaks "Nevermore" reflects the same real-world observation of raven vocal mimicry in captivity (see Dickens's Grip). The ancient reputation of ravens as oracular or prophetic birds almost certainly stems in part from their uncanny vocal abilities.

Related Pages

• Can ravens talk? — myth check
• Raven intelligence
• Raven social structure