Hummingbird

Ecological communities that experience stable climate conditions have been speculated to preserve more specialized interspecific associations and have higher proportions of smaller ranged species (SRS). Thus, areas with disproportionally large numbers of SRS are expected to coincide geographically with a high degree of community-level ecological specialization, but this suggestion remains poorly supported with empirical evidence. Here, we analysed data for hummingbird resource specialization, range size, contemporary climate, and Late Quaternary climate stability for 46 hummingbird–plant mutualistic networks distributed across the Americas, representing 130 hummingbird species ( ca 40% of all hummingbird species). We demonstrate a positive relationship between the proportion of SRS of hummingbirds and community-level specialization, i.e. the division of the floral niche among coexisting hummingbird species. This relationship remained strong even when accounting for climate, furtherm...

Although a few hummingbirds are common inside cities, few is known about their feeding habits, which allow their coexistence in these modified environments. During the period of one year, it was observed which hummingbirds occurs in urbane gardens in the city of Getúlio Vargas, their behaviors and which plants they feed on. Eight species of hummingbirds were found, of which Eupetomena macroura and Amazilia versicolor are new occurences in the north region of Rio Grande do Sul. Of the 51 agonistic interactions, the species Leucochloris albicollis and Chlorostilbon lucidus were the most agressives ones, and also the ones that visited the biggest number of species of plants. It is still possible to suggest an altitudinal migration of C. lucidus in the state of Rio Grande do Sul during the cold months. It was reported 22 botanical families used by those birds, being Bignoniaceae, Fabaceae and Malvaceae the most visited. The main blooming season was in the months betwen September and December. Out of the 31 plants visited, 19 are considered exotic (61,3%) and 12 are native (38,7%); eight are ornitophilous (25,8%) and 23 are entomophilous (74,2%), what indicates an adaptation of these birds to the resources inside the cities. Handroanthus chrysotrichus had the smallest blooming time, however, was one of the species that attracted the biggest number of hummingbirds: five species; Callistemon viminalis was in bloom during the whole year, and equally attracted five species of hummingbirds. As reported in other studies, all the plants visited have colors variating between white tones, yellow and red, being the ones with tube corollas the most visited (51,6%). It can be concluded that, if mantained, the gardens can act as feeding support to the hummingbirds in a modified environment.