Azure-crowned Hummingbird

The azure-crowned hummingbird is 10 to 11.5 cm (3.9 to 4.5 in) long. Males weigh an average of about 5.8 g (0.20 oz) and females average about 5.4 g (0.19 oz). The bills of both sexes of both subspecies have a black maxilla and a dull pink mandible with a black outer third. Within a subspecies the sexes are almost alike. Adult males of the nominate subspecies have a bright metallic blue crown and females a duller blue to greenish blue crown. Both sexes have metallic bronze nape and back. They have greenish bronze to bronze green rump, uppertail coverts, and tail. Voice: One vocalization of the azure-crowned hummingbird is "a low, fairly hard, buzzy dzzzrt" that is given in flight and perched; when perched it might be "repeated steadily". It also makes a "fairly mellow, strong chipping at times run into a trill or rattle." The vocalizations of isolated subspecies S. c. chlorostephana might be different but have not been separately described.