Red-crested Cardinal is generally found in pairs or in small groups of roughly 2.85 ± 0.3 individuals (Segura et al. 2014). During the nonbreeding season travles in flocks of up to 25 individuals (Belton 1985). Its primary mode of foraging is ground glean, and it occurs in pairs or small groups along with other local species (Ridgely and Tudor 2009).
During the breeding season, Red-crested Cardinal pairs are very territorial of the nest site, with the males chasing off other members of the species or potential predators from the nest. Territory size is unknown (Segura and Arturi 2009, Segura et al. in press). Outside of breeding season Red-crested Cardinal easily coexists with others of its species and other local avifauna (Kratter et al. 1993).
The breeding season for Red-crested Cardinal extends from early October to mid-February (Segura and Arturi 2009). The species is monogamous throughout the season, and both sexes sing to keep in vocal contact with each other (Pendleton 1996, cited in Lindholm 2003). Observed courting behaviors include both sexes strutting, fanning their tails, and arching their backs, while the female will clack her beak to express interest in a male. Mating occurs as a swift series of attacks by the male while the female is on the ground and inattentive (Pendleton 1996, cited in Lindholm 2003).
Social and interspecific behavior
Red-crested Cardinal is often seen foraging on the ground out in the open in pairs or small groups, and can be in larger flocks during the non-breeding season (Belton 1985, Ridgely and Tudor 1989). It also associates with mixed flocks, including such species as Red-crested Finch (Coryphospingus cucullatus), Many-colored Chaco Finch (Saltatricula multicolor), Ultramarine Grosbeak (Cyanocompsa brissonii), and Stripe-capped Sparrow (Rhynchospiza strigiceps) from June to September in the chaco (Kratter et al. 1993). Where P. coronata’s range overlaps with Yellow-billed Cardinal (P. capitata) the two species appear to compete, and there has also been a report of the two species hybridizing and producing fertile offspring (Sick 1993).
There are little data on predation against adult Red-crested Cardinals. Most predation is on the cardinal’s nest and eggs during the breeding season, where as many as 88% of nests (61 nests out of 69) suffer nest predation during the season (Segura and Berkunsky 2012). Most potential predators are speculated to access the nest from above, and potential aerial predators found in the same areas as Red-crested Cardinal during their breeding season include Guira Cuckoo (Guira guira), Chimango Caracara (Milvago chimango), and Narrow-billed Woodcreeper (Lepidocolaptes angustirostris), while terrestrial predators might include White-eared Opossum (Didelphis albiventris), Lesser Grison (Galictis cuja), snakes (Philodryas spp.), and small rodents (Segura et al. 2012). In a lab experiment, Segura and Reboreda (2012b) introduced a stuffed mount of a Guira Cuckoo to nesting Red-crested Cardinals, and found that, during the incubation and nestling stage of breeding, the parents responded by increasing the frequency of distress calls and the males made direct attacks against the model.