Why hummingbirds hover

Hummingbirds are noted for their hovering flight, and it has been shown that a bird that hovers can move more quickly between flowers than one that perches. Because the relative importance of energetic costs vs. speed increases with body size, it has been assumed that if birds forage in ways that maximize their net energy gain, small birds, such as hummingbirds, should hover and large birds should perch. This study shows that hovering is not necessarily the preferred mode of feeding in hummingbirds, and that floral architecture, rather than energetics, dictates whether a bird hovers or perches.