Hummingbird-plant interactions in Chile: An ecological review of the available evidence

Abstract

Hummingbird species have closely evolved with the plants they feed on, which is confirmed by their often tight ecological relationships in natural settings. Hummingbird-plant interactions are of interest for research areas such as ecology, evolution, and even agriculture, as they usually inform on the conservation status of interacting species assemblages, and its disappearance may precede the population extinction of the species involved in the interaction. In Chile, there are nine hummingbird species, which interact with a large and diverse number of angiosperm species in forest, desert, and mountain range environments. The motivation to perform this review is to systematize the available information regarding the flowering plants visited by hummingbird species in Chile, to present some basic plant-hummingbird pollination network metrics, and on this basis to identify the components of the plant-hummingbird relationships in need of further research. A plant-hummingbird metanetwork revealed a low connectance value, low niche overlap, and strong modularity among species. However, the fact that most species present a strong allopatric distribution across Chile, suggests that network structure results mostly from the history of colonization rather than from ecological organization. Nowadays, the main threats to Chilean hummingbirds are anthropogenic disturbance and climate change, which disrupt hummingbird-plant interactions, leading to unpredictable ecological consequences at the community level. Long periods of drought may reduce the resource base for hummingbirds, with dramatic consequences for the maintenance of bird and plant populations.