Sounds

Figure 3. Turwheit calls of the Snowy Plover

Vocalizations

Development

Chicks make a repeated peep from up to 2 d before hatching until about the time they first fly. Free-ranging chicks use this call during close pursuit or capture by a predator or person and when isolated from parent (GWP). D. George (pers. comm.) reports finding 2 crouched chicks making a soft trilling call, distinct from repeated peeping call.

Vocal Array

Adults use at least 3 primary calls during breeding season.

Purrt. Repeated several times. Given by either sex while flying singly or together from nesting territories, during courtship while scraping or tossing (see Breeding: nest) in presence of mates, during or immediately after conflicts with other plovers that have invaded their nesting territories or closely approached their broods, while a person handles their eggs or chicks, while attending their broods in the absence of any obvious intrusion by another plover or other intruder, and (in one instance) by a male fluttering over vegetated habitat toward a slough in an apparent attempt to encourage his chicks to follow (JSW and JCW).

Turwheit or Towheet. Figure 3. Usually repeated a few to many times by males, when unmated and standing or scraping in territories in absence of females (advertisement), from territories while standing or scraping in presence of a female prior to nesting (courtship), from territories in absence or presence of mates while clutches are still incomplete, and from territories during confrontations with intruding plovers while standing in Upright Posture (see Behavior: agonistic behavior), chasing invaders, or standing between bouts of fighting (threat and aggression). This call is repeated by either sex as a predator destroys their eggs (distress), while brooding or standing near their chicks in absence of any other obvious plover or intruder, during confrontations with other plovers when attending chicks (threat and aggression), and from ground or in flight when a person closely approaches their flightless young (alarm). Call is quieter, hoarser, and more abbreviated in females than in males (JSW and JCW). Probably analogous to peo-eet call attributed to a Snowy Plover in Kansas after it had run from its nest at the approach of an intruder (Boyd 1972).

Churr. Usually not repeated and most often made by males, sometimes during courtship activities such as scraping or debris tossing, but most often during agonistic encounters with other plovers during defense of nesting territories or broods. During these aggressive encounters, calling male stands in Upright Posture, chases, or fights with intruding plovers. Females utter this call during confrontations with other species (e.g., Black-bellied Plover [Pluvialis squatarola]) or conspecifics near their nests or chicks. In aggressive situations, this call is frequently combined with 2 other notes to produce a whit whit churr or a purt purt churr (JSW and JCW).

Ti. During nonbreeding season, a repeated, low, tinkling ti note, uttered by plovers disturbed at their roosts, often signals flight of some or all birds.

Phenology

In coastal California, calls associated with breeding are used from late Jan until Sep; ti of nonbreeding period is used from Aug to Apr.

Daily Pattern Of Vocalizing

Breeding-season calls given day or night, but nonbreeding-season calls only reported for daylight hours.

Places Of Vocalizing

Most calling is from ground, but all breeding-season calls also may be given in flight (JSW and JCW). In contrast to Kentish Plovers (C. a. alexandrinus), Snowy Plovers (C. a. nivosus) do not employ a flight song to advertise territories (Warriner et al. 1986).

Nonvocal Sounds

None known.