They are principally birds of low-altitude woodlands and forests, and particularly of forest edge and canopy.
Jacamars are insectivores, taking a variety of insect prey (many specialize on butterflies and moths) by hawking in the air. Birds sit in favoured perches and sally towards the prey when it is close enough. Only the great jacamar varies from the rest of the family, taking prey by gleaning and occasionally taking small lizards and spiders.
The jacamars are small to medium-sized perching birds, they are elegant, glossy birds with long bills and tails. In appearance and behaviour they resemble the Old World bee-eaters, as most aerial insectivores tend to have short, wide bills rather than long, thin ones. The legs are short and weak, and the feet are zygodactylic (two forward-pointing toes, two backward-pointing). Their plumage is often bright and highly iridescent, although it is quite dull in a few species.
There are minor differences in plumage based on sex, males often having a white patch on the breast. Of the 18 species that exist, Costa Rica has 2 of them.