Hispaniolan Crossbill is a nomadic species that moves between suitable foraging areas. Often quiet and secretive, they sometimes occur in noisy flocks feeding on pine seeds, which they extract from cones by prying apart scales with a crossed bill (Latta et al. 2006). During the nesting cycle, males feed the female regurgitated boluses, which the female repeatedly regurgitates and masticates before final consumption (Latta et al. 2002).
Few antagonistic behaviors are described. Latta et al. (2002) report one observation of a male crossbill swooping at a Merlin and giving harsh chut calls after the Merlin perched 10 m from the crossbill nest. The Merlin subsequently left the area. No antagonistic behaviors reported among crossbills.
Males defend nesting territory from other species around nest site during nest construction and egg-laying, but little evidence later in nesting cycle (Latta et al. 2002).
Courtship involves song, aerial chases, bill touching, and courtship feeding. Courtship feeding takes place during nest construction and is preceded by billing, nibbling, and the female quivering her wings and tail (Latta et al. 2002). Latta et al. (2002) observed a pair giving chit notes that may function in formation and maintenance of the pair bond.
Social and interspecific behavior
Often found in family groups following breeding (Latta unpubl. ms.). Mean flock size in the Sierra de Bahorucos is 5.4 individuals (SD = 2.3, range = 1-20, n = 40; Latta et al. 2002). Largest flock observed contained 18 individuals in Macaya Biosphere Reserve (C. Rimmer pers. comm.). Flocks are often observed moving between trees in search of seeds. Foraging is more intense in the mornings with drinking and bathing more common in the late afternoon (Latta et al. 2002). A female observed sitting on eggs gave 2-4 chit calls in response to a flock of crossbills flying overhead; no response was observed by individuals in the flock (Latta et al. 2002).
During incubation, parents tolerate foraging birds 0.3-15 m away in the nest tree. Tolerance is known for Hispaniolan Pewee (Contopus hispaniolensis), Yellow-throated Warbler (Dendroica dominica), Pine Warbler (Dendroica pinus), Palm Warbler (Dendroica palmarum), Black-and-white Warbler (Mniotilta varia), and Black-crowned Palm-Tanager (Phaenicophilus palmarum). During brooding, non-predatory birds (Hispaniolan Pewee and Prairie Warbler) are tolerated within 8 m of nest (Latta et al. 2002).
No known observations of nest predators. Possible predators include Indian mongoose (Herpestes auropunctatus), Hispaniolan boa (Epicrates striatus), Merlin (Falco columbarius), Barn Owl (Tyto alba), Ashy-faced Owl (Tyto glaucops), Stygian Owl (Asio stygius), and Hispaniolan Palm Crow (Corvus palmarum; Latta et al. 2002). Crossbill bones were found in Ashy-faced Owl pellets in a sinkhole in Morne de la Selle (Wetmore and Swales 1931).