Behavior

Rose-throated Becards when alone can be quite inconspicuous and often are silent. They may spend minutes at a time on a sheltered perch as they watch the surrounding foliage and air column (Dickey and van Rossem 1938, L. I. Davis in Bent 1942). Flight behavior is mostly undescribed, and self-maintenance and agonistic behaviors are unreported in the literature that I have seen. As one might expect in a species that spends time hawking flying insects, becards are adept in the air. One male deftly caught a tuft of plant down floating downwards before it reached the ground (Skutch 1969). Skutch also observed females returning to the nest fly straight into the nest interior through the entrance without first clinging to nest material on the outside.
Rose-throated Becards have an erectile crest, which when raised give the head a bushy or ragged crown profile (see Image Gallery). Ruffling or raising of crown feathers is widespread in birds, even in those species that do not have modified crest feathers. This behavior in other species may express disturbance and a tendency to flee, or sexual impulses, that are temporarily thwarted (Morris 1956). Crest raising is also displayed by subordinates in some dominance relationships (e.g., Hinde 1953). Yet, little is known about this visual display in Rose-throated Becards.

Much remains to be learned about basic natural history in this species. Most behavioral information in the literature focuses on birds around their striking nests, emphasizing nest-building to parental care stages (see Reproduction).

Rose-throated Becard apparently is territorial, but agonistic behaviors are undescribed. Pairs isolate themselves from neighbors and express intolerance and territorial defense at the beginning of the breeding season (Forcey 2002). In Oaxaca, Mexico, two active nests in an arroyo were as close as 70 m apart, but most are more widely separated (Forcey 2002). In a study in Tamaulipas, Mexico, Gehlbach (1987) reported that "nesting territories" were dispersed about 150 m apart along a local river.

Very little is known about pairing, courtship, and other sexual behaviors in the species. Rose-throated Becards are socially monogamous, but pair bonds, at least in some environments with strong seasonality, especially with respect to temperature (e.g., at northern edges of range, highlands of western Guatemala where heavy frosts can occur in certain months), may not persist during the nonbreeding period (Skutch 1969; Appendix 1 ). Apparent bond-related behavior, which may be used in pairing and courtship, involves the display of a hidden patch of white feathers on the shoulders by males (Skutch in Bent 1942, Skutch 1969). These "epaulet" patches have not been mentioned in any plumage description, or portrayed in any illustration, that I have seen. Yet, Skutch’s (1969) behavioral description leaves little doubt that when erected, the patches are quite conspicuous. A breeding male often raises these feathers when he is approaching his mate at or near the nest after a separation from her. The behavior is accompanied by a swaying motion of the body on a perch. Details of this visual display, including frequency of use and other contexts in which it may be employed, remain to be investigated. Extrapair mating is unreported in the species, but the attentiveness of the male to the female (Skutch 1969, Brush 2005) during nest-building, when he often follows her on long trips away from the nest, may imply a potential importance of this behavior in its social system (Kokko and Morrell 2005).

Social behavior is mostly mate- and family-oriented, but little is known about it. Males often follow a mate (see Sexual Behavior) on foraging excursions or collection trips for nest material. The male also is prone to call to his mate when she may be inside the nest when he returns from an absence (Skutch 1969). She often calls back or leaves the nest and joins him at such times. Apparently membership in mixed species foraging flocks is limited to one or two birds (Skutch 1969, Hutto 1994), suggesting little social interaction during the nonbreeding season when such flocks are prevalent.

A notable characteristic of breeding Rose-throated Becards concerns their apparent tendency, at least in northern parts of the breeding range, to form nest associations in the same tree with a few other species, especially with tyrannids and orioles. W. L. Dawson (Bent 1942) first observed this behavior during the 1920s in relation to Thick-billed Kingbird (Tyrannus crassirostris), Social Flycatcher (Myiozetetes similis), and Streak-backed Oriole (Icterus pustulatus) in Mexico. Dickey and van Rossem (1938) mentioned the same behavior in El Salvador involving Altamira Oriole (Icterus gularis), Streak-backed Oriole, and Spot-breasted Oriole (Icterus pectoralis) as associates. Rowley (1984; Oaxaca) reported on one such nesting community that comprised nests of six species, including Tropical Kingbird (Tyrannus melancholicus) and Vermilion Flycatcher (Pyrocephalus rubinus). Gehlbach (1987; Tamaulipas, Mexico) and T. Brush (in litt.; Yucatan Peninsula) also noted same-tree nest associates. Gehlbach added Great Kiskadee (Pitangus sulphuratus) to the list, while Brush wrote that “…becards are common nesting associates of Altamira Orioles [I. gularis] and other birds….” Presumably, becards, and perhaps other vulnerable species, gain some communal nest protection from species that are notably aggressive to intruding predators, although not to human predators (Rowley 1984).

Rose-throated Becards regularly strip their old nests to build a new nest nearby, so it should be no surprise to learn that they pilfer material from the active nests of other species nearby as opportunities arise (Rowley 1984). This behavior often leads to interspecific intolerance towards becards near the nests of some tyrannids or orioles that are breeding in the same neighborhood (Brush 2000). In the same-tree, six-nest community mentioned above, “continual piracy of materials from each other’s nests” reigned, even though the species there overall appeared to live amicably together (Rowley 1984:210)—evidently because most pilfering took place when victims were away from their nests.

No information on the importance of predators in the lives of Rose-throated Becards. Most nests seem to be relatively inaccessible, so the effects of arboreal snakes and climbing mammals on nest risk remain to be evaluated. Anti-predator behavior (alarm calling, 'mobbing' behavior) by adult becards near the nest (Howell and Webb 1995) or associated with a juvenile (Davis 1945) has been reported but is undescribed.