Competition between hummingbirds and insects for nectar

Abstract

Preliminary data are provided suggesting that hummingbirds compete with bees and hawkmoths for flower nectar while on southward migration through the Sierra Nevada of California during the summer. Evidence is given that removal of hummingbirds enhances foraging in bees and hawkmoths on plants shared with the birds. The birds were aggressive against moths but not usually against bees. Competition between these taxa leads to temporal and spatial partitioning of the resource that is apparently behaviorally mediated. It is speculated that for hummingbirds competition with insects is less predictable and more difficult to contend with than is competition with other hummingbirds. © 1979 by the American Society of Zoologists.