Sounds

Vocalizations resemble those of other large gulls; no specific studies. Calls similar to those of Herring Gulls (detailed in Pierotti and Good 1994), but much lower pitched.

Development

First vocalizations, peeping sounds, produced when egg is pipped before hatching. Newly hatched chicks give Begging Call. As chicks grow, Begging Call changes from simple peep with head lifting slightly to more intense peeping with head thrust head forward and mouth open to high-pitched peep with head hunched against body, lifting head each time they emit peep . Call appears identical to Begging Call in adults (see below).

Chicks also given harsh Shrill Waver when being pursued or grabbed by predator, conspecific, or investigator. The vocalization produced by adults in similar contexts is similar to Alarm Call (see below; Tinbergen 1960).

First-year birds give Long Call without accompanying posture (Cramp and Simmons 1983). Three-year-old birds give Long-Call Note, Long Call, and Warning Call (Tinbergen 1960). Calls specifically associated with mating and chick-rearing (Mew, Choking, and Copulation calls) are observed only in breeding (4- to 5-yr-old) birds. Away from breeding colonies, generally silent; several birds together may be noisy, especially when feeding.

Auditory Ability

No data reported. Gulls possess more limited tuning properties and more restricted sound frequency spectrum than domestic fowl (Counter and Tsao 1986).

Vocal Array

No “song,” but species has complex repertoire of calls. No specific studies. Two of these calls (Begging Call and Shrill Waver) used by prefledged chicks; 3 others (Mew, Choking, and Copulation calls) used exclusively by adults during breeding. Calls are influenced by body posture. Behavioral acts are associated with calls (see Behavior, below). Description of calls follows Moynihan 1955 and 1958, and Tinbergen 1959 and 1960, except where noted.

Long Call. Also called Trumpeting (Tinbergen 1960). Most elaborate and variable call in repertoire. Consists of several repeated notes produced while bird lowers and then elevates head to Oblique Posture (less extreme than in Herring Gull; see Behavior: agonistic behavior, below). First note(s) longer and lower; subsequent notes louder and higher pitched. Final notes flatter and lower pitched. In mate interactions, given by both members of pair when 1 returns after absence. Directed at mates by males more than by females during breeding; frequency of call by both sexes increases after chicks hatch (Butler and Janes-Butler 1983). Elicited by chicks continuously soliciting feeding and/or mandibulating bills of recumbent adults; given by males more than by females when chicks left and/or returned to territory, especially if neighboring adults were nearby (Butler and Janes-Butler 1983). In agonistic contexts, given by both sexes—males more than females—during conspecific overflights of territory, during neighbor interactions, when other adults give Long Call or Long-Call Note (see below), or directed at nonneighbor before higher-level response; frequency of call by both sexes increases after chicks hatch (Butler and Janes-Butler 1983).

Long-Call Note. Also called Keow or Yelp. Deep, low-intensity, single-note version of Long Call. Heard most often during breeding, when individuals are crowded together. Functions in individual identification; given when predator approaches and by birds observing other birds fighting. In mate interactions, given by both sexes, males more than females, before their own or mate’s aerial departure from territory during breeding (Butler and Janes-Butler 1983). Given by adults before they feed chicks; given by both sexes, males more than females, when chicks are out of sight in dense vegetation or are too close to territorial boundary or neighboring adult (Butler and Janes-Butler 1983). In agonistic contexts, given infrequently by both sexes during conspecific overflights of territory, during neighbor interactions, when other adults give Long Call or Long-Call Note, or directed at nonneighbor before higher-level response (Butler and Janes-Butler 1983).

Warning Call. Also called Yeow or Plaintive Yeow. Slightly descending call; differs among individuals primarily in duration. Heard most frequently when visitor disturbs breeding colony. Given by both sexes during high-level agonistic interactions near territorial boundary. Given when adults and chicks of 2 territories are close to mutual boundaries, when adult’s chick is in adjacent territory, when a calling bird intrudes into adjacent territory, or on windy days when large numbers of adults soar over calling gull’s territory; frequency of call by both sexes increases after chicks hatch (Butler and Janes-Butler 1983).

Mew Call. Drawn-out single note invariably linked with distinctive forward bent posture (neck stretched forward and arched). In courtship, given primarily by male after returning from absence when about to regurgitate food for mate-feeding; may call mate to be fed. Parents carrying food also use Mew Call to attract offspring; can give call with beak full of food. Given by adults when chicks out of sight in dense vegetation or when chicks wander too close to territorial boundary or neighboring adult (Butler and Janes-Butler 1983); given more frequently in high-density territories (Butler and Trivelpiece 1981). In nest relief, given by bird approaching nest, sometimes with nesting material in beak. In these cases appears to function as affiliative call, to get attention of mate or chick; given by males more than by females before chicks hatch; frequency of call given by both sexes decreases after chicks hatch (Butler and Janes-Butler 1983). In aggression, given by birds that appear highly agitated; can be last vocalization produced before birds attack or are attacked. In absence of territorial pair, given by intruding adult(s) to hiding chick or adjacent territory holders (Butler and Trivelpiece 1981).

Begging Call. Simple call, accompanied by Head-tossing, in which bird assumes hunched posture and flicks head up sharply while emitting call (see Behavior: agonistic behavior, below). Given by female in response to Mew Call by returned male; also given by both male and female before mounting. Call virtually identical to Begging Call of chicks, except has softer, less demanding quality.

Copulation Call. Loud and regular in rhythm, staccato and guttural in quality. Call produced by male after mounting, initiated during phase when tail is lowered and cloacal contact begins, continued until completion of copulation.

Choking Call. Usually performed in tandem by mated pair. Named after accompanying visual display, in which bird squats, or crouches, with breast lowered to ground and tail elevated (see Behavior: agonistic behavior, below). Utters call as head and neck pump with hyoid bone lowered, producing hollow, guttural huoh-huoh-huoh sound. Occurs in 3 contexts: (1) agonistic encounters, where territorial birds engage neighbors across shared boundary; (2) early stages of courtship, especially during nest-site choice; and (3) during nest exchanges. In agonistic contexts, given by both sexes during conspecific overflights of territory, during neighbor interactions, when other adults give Long Call or Long-Call Note (see above), or directed at nonneighbor before higher-level response (Butler and Janes-Butler 1983). In mate interactions, given by males more than by females before chicks hatch; frequency of call given by males decreases after chicks hatch (Butler and Janes-Butler 1983).

Alarm Call. Also called Gakker, Eh-Eh, or Kek-Kek Call. Given in response to predator (observer), especially on breeding colony; given more frequently than by Herring Gulls at approach of humans (Burger and Gochfeld 1981). Given primarily when predator is first seen but does not pose immediate threat. If predator comes closer, birds shift to Long-Call Note or take to air, uttering Warning Calls. Often alternates with Charge Call, so may also indicate conflict between flight and attack. Given infrequently by both sexes during high-level agonistic interactions near territorial boundary. Given when adults and chicks are close to mutual boundaries, when a chick is in adjacent territory, when a calling bird intrudes into adjacent territory, or on windy days when large numbers of adults soar over calling gull’s territory; frequency of call by both sexes increases after chicks hatch (Butler and Janes-Butler 1983).

Charge Call. Given when diving at intruder or predator, or during aerial pursuit of conspecific or predator. Tinbergen (1960) regards this as modified Long-Call Note; however, more similar structurally to Mew Call (Hand 1979) and may indicate high state of arousal.

Shrill Waver. As described for chicks (see above). Given when bird is grabbed or attacked unexpectedly, either by predator or by conspecific. Structurally related to Begging Call; deeper and more guttural than that of Herring Gull. Females grabbed by mate or male they are courting may engage in Head-Tossing (see Behavior: agonistic behavior, below), give Shrill Waver (see above), or combine the 2.

None described.