One of the characteristic sounds the montane west, Steller’s Jay has a large variety of loud (and often harsh) calls, mimetic calls, and a quiet, warbling “song” ( Brown 1964b , Pustmueller 1977 , Hope 1980 ). In addition to their oft-heard harsh calls, a host of lesser-used vocalizations have been described. The vocal array below is arranged with the most common vocalizations first, and the rarer call types following.
The following information was extracted from studies by Brown ( Brown 1964b ) and Hope ( Hope 1980 ) of C. s. frontalis in Alameda and Contra Costa counties, CA. Information on acoustic characteristics of calls comes from Pustmueller 1977 , Hope 1980 , and recordings made in w. Montana (WD, EG).
Little information. During first 10 d, chick produces high-pitched squeaking call when nest is touched ( Hardy 1961b ). Louder begging calls develop during last part of nestling phase: Gurgle (see Figure 3A) and Bah (Figure 3B) resemble adult Wah (see Figure 3I), but louder, irregular in duration, and higher frequencies emphasized ( Hope 1980 ). Juvenile produces Gurgle when fed. Grate ( Figure 3C, 3D; or Juvenile Rattle of Brown 1964b ) is rapid series of irregular notes; similar to Rattle (see Figure 3O), but interval between individual notes less regular; used in different contexts, such as interacting with other juveniles and responding to adult Song (see Figure 3N). Juvenile bird may produce irregular, poorly structured Song-like vocalizations in autumn.
Abbreviations in following section: NL, note length (s); NR, note rate (notes/s); FR, frequency range (kHz); DF, dominant frequency (kHz); INF, inflection. Data given as mean ± 2 SE.
Guttural Notes. Composed of many intergrading types; repeated notes of short duration, wide frequency range.
Ut. Low-intensity guttural note, given with bill closed. Produced by both sexes; commonly produced by mates when close to each other, or by groups of birds. NL = 0.10 ± 0.01; FR = 0.5–4; DF = 1.8 ± 0.3; INF = none.
Aap (Amp). Given at range of intensities, from normal perching posture. At higher intensities, usually associated with Wing-Spreading (see Behavior: Agonistic Behavior); given by both sexes throughout year, but most common during early breeding cycle. Produced in many different social contexts, such as nest-building, courtship-feeding, boundary disputes, and close-range contact between mates or among a group of birds. NL = 0.13 ± 0.02; NR = 2.1 ± 0.3; FR = 1–6; DF = 3.2 ± 0.5; INF = down.
Wek. Loudly repeated wek ( Hope 1980 ) or shook ( Brown 1964b ); up to 5 repetitions. Produced in wide variety of social contexts, including perched alone, in groups, in flight, during chases, in response to sudden disturbances and agonistic interactions between conspecifics and other species, and as alarm call in response to raptors. Produced by both sexes all year; call of female slightly higher pitched, more metallic-sounding than that of male. Note rate varies according to intensity of interaction, from about 5 notes after gatherings or fights to 10 notes during alarm calling or escalated fights; intermediate during gatherings and chases ( Hope 1980 ). NL = 0.09 ± 0.01; NR = 6.8 ± 0.4; FR = 1–4.5; DF = 2.6 ± 0.3, INF = circumflex.
Audio Example: ML 42204.
Ow. Relatively rare call; rapid sequence of loud, nasal notes; higher pitched than Wek (see above). Most frequently heard during spring by birds in highly excited groups. Often accompanied by Wing-Spreading (see Behavior: Agonistic Behavior). NL = 0.15; NR = 4.1; FR = 0.8–6.5; DF = 3.0; INF = circumflex.
Wah. Harsh, nasal call with slurred beginning, typically ending with downward inflection. Both sexes produce call throughout year, most commonly in Mar and Apr. Given singly or repeated at rate of about 1/s. Produced in many contexts: alarm call, predator-mobbing call, submissive begging by juveniles, and aggressive sidling, just after alighting. NL = 0.32 ± 0.02; NR = 2.0 ± 0.3; FR = 0.5–7; DF = 3.2 ± 0.2; INF = none or down.
Audio Example: ML 168982.
Growl. Variant of Wah (see above), noticeably down slurred. Produced all year, but most common in Mar and Apr, typically in conjunction with Aggressive Sidling, Tail-Flicking, Wing-Flicking, and Tail-Spreading displays (see Behavior: Agonistic Behavior). NL = 0.51 ± 0.03; NR = 1.5 ± 0.1; FR = 1–6; DF = 2.7 ± 0.5; INF = none.
Creak. Produced only by male; resembles high, muted whistle, composed of fundamental tone with one or more overtones, usually ending with abrupt popping sound. Much individual variation. Calls of 3 males were described as “oot”, “toodle-oot”, and “woot” ( Brown 1964b ). Given all year, but most common in early breeding season and in warmer days of fall. Given in aggressive contexts by flying and perched birds, usually in supplanting or threatening contexts. Also produced by males during Sexual Sidling (see Behavior: Sexual Behavior), especially if female gives Rattle. Since Creak and Rattle are sex-specific, they are believed to have special role in courtship and pair formation. NL = 0.28 ± 0.2; NR = 2.1 ± 0.2; FR = 1.5–5; DF = 2.6 ± 0.3; INF = wavering.
Squawk. Loud, noisy, and rarely repeated “ awk ” or “ cac .” Produced when pursued by predator. NL = 0.4; FR = 1.5–6.
Tjar. Complex call; first part resonant, second part lower; descending in pitch; harsh and noisy. Infrequently heard; caller usually in conspicuous location and produces call repeatedly; function unknown ( Hope 1980 ).
Song. Produced mainly by male, but also occasionally by female. Consists of low-amplitude series of whistled, gurgled, snapping, popping, or harsh sounds; run together with frequent repetitions. Produced in several social contexts: during courtship, primarily by male during Sexual Sidling and Courtship-Circling (see Behavior: Sexual Behavior); solitary individuals perched in dense vegetation will sing with no apparent stimulus; individuals occasionally sing during other activities, such as foraging; adults observed apparently singing to juveniles ( Hope 1980 ). Singing bird often continues for several minutes with slight pauses; holds tail and body in line and nearly vertical. Extends head forward slightly, and slowly turns it from side to side.
Rattle. Produced only by female; mechanical-sounding series of clicks covering a wide frequency range; lasts 0.5–2 s or longer. Produced throughout year, most commonly during early breeding season; typically within or near border of caller's territory in response to presence of other jays. Given in both sexual and agonistic contexts. May serve to attract both mated and unmated jays to centers of courtship activity. NL < 0.01; NR = 41.0 ± 2.9; FR = 1–5.0; DF = 2.0 ± 0.2; INF = slightly upward.
Tee-ar. Whistled note with slow, downward slurring; produced slowly and singly, primarily by male. Resembles scream of Red-tailed Hawk (Buteo jamaicensis). Given while perched and in flight. Often given by hidden bird, and when no Red-tailed Hawk apparent. NL = 1.10 ± 0.16; FR = 1.8–3.5; DF = 2.6 ± 0.4; INF = down.
Mimicry. Good mimic; often heard imitating sounds of other animals in area, including those of fox squirrel (Sciurus niger; Brown 1964b ), Northern Flicker (Colaptes auratus; WD), Northern Goshawk (Accipiter gentilis; Kennedy and Stahlecker 1993 ), White-breasted Nuthatch (Sitta carolinensis; C. Ghalambor, personal communication), chicken, and rooster (Gallus gallus), dog (Canis familiaris), cat (Felis domestica), and mechanical sounds such as water sprinklers, telephone, and squeaky door (WD, EG).
Local Calls. In addition to the widespread vocalizations described above, there are endemic vocalizations specific to individual jay populations ( Brown 1964b , Pustmueller 1977 , Hope 1980 ). Function unknown. Local sounds might be unique to particular populations, but new functional categories most likely do not arise in different populations.
Vocalizations of Steller's and Blue jay hybrids include calls of both parental species, as well as vocalizations unique to hybrids ( Hardy and Wheat 1982 ).
Seasonal variation in frequency of different calls was studied near Berkeley, California ( Brown 1964b ). Frequency of Rattle, Creak, Ow, Growl, Wah, and Wek, low during Jan; all increase to a peak in Mar and early Apr, decrease to low frequency in Jan; secondary peak in vocalizations in Jul and Aug, especially for Rattle, Wek, Creak, and Wah .
Places Of Vocalizing
Birds vocalize in flight, while perched in trees, on ground, and while interacting with other jays.
Using electrical stimulation of brain (ESB), research has investigated the neural organization of agonistic behaviors such as crest displays (see Behavior: Agonistic Behavior) and vocalizations ( Brown 1973c ). Brown identified regions of anterior hypothalamus, nonauditory portion of torus semicircularis, and adjacent mesencephalicus lateralis ventralis associated with agonistic behaviors. Crest erection and Wah calls were evoked by ESB, and graded in accordance with intensity of ESB; no other vocalizations were reliably evoked with electrical stimulation of these areas.