The blue-necked jacamar is long and weighs. The male's upper parts are shiny green and the underparts chestnut. The face is steely blue to green on an east to west gradient. The female is duller and its underparts are tawnybuff.
The blue-necked jacamar's diet is a large variety of insects. It perches on exposed branches and sallies from there to catch its flying prey.
Breeding
Two blue-necked jacamar nest burrows were found in arboreal termite nests in Brazil, one in June and the other in October; each held two eggs. Birds in breeding condition were found in September.
Vocalization
The voice of the blue-necked jacamar is essentially the same as that of the yellow-billed. A song is here and a call here.
Status
The IUCN has assessed the blue-necked jacamar as being of Least Concern. It occurs in several protected areas and is generally common over its range. However, "Owing to its greater reliance on intact forest understorey, this species, as G. albirostris, is likely to be more susceptible to deforestation than are most other jacamars."