A Geographic Mosaic of Plant–Pollinator Interactions in the Eastern Caribbean Islands. (7th August 2012)

• Record Type: Journal Article
• Authors: Gowda, Vinita; Kress, W. John
• Is Part Of: Biotropica. Volume 45:Number 2(2013:Mar.)
• Page Start: 224
• Page End: 235
• Publication Date: 2012-08-07
• Subjects: Biotic communities -- Tropics -- Periodicals; Applied ecology -- Tropics -- Periodicals; Biology -- Tropics -- Periodicals; 577.80913
• DOI: 10.1111/j.1744-7429.2012.00915.x
• Languages: English
• ISSNs: 0006-3606

Abstract

<abstract abstract-type="main" id="btp915-abs-0001"> <title>Abstract</title> <p>The interplay between generalized and specialized plant–animal interactions is a core concept in understanding the evolution of mutualisms. Within the Eastern Caribbean, <italic>Heliconia bihai</italic> is a dominant forest species in the southern island of St. Vincent where <italic>H. caribaea</italic> is virtually absent. <italic>Heliconia caribaea</italic> is most common on the northern island of St. Kitts where <italic>H. bihai</italic> is restricted to the tops of the highest peaks. Both species are abundant on the central island of Dominica. We compared flowering patterns, nectar characteristics, and visitation frequency of hummingbirds in the two heliconias on the three islands to determine the extent of geographic variations in this plant–pollinator mutualism. The peak flowering season of the two heliconias was observed to be in April–May on all three islands with little within‐ and between‐island variations. Nectar production significantly varied between species and between islands. Visitation patterns by the principal hummingbird pollinators also varied between the islands: (1) on Dominica, only females of a single species of hummingbird pollinated the flowers of <italic>H. bihai</italic> (sexual specialization), whereas both sexes of the same hummingbird pollinated the flowers of <italic>H. caribaea</italic> (species specialization); (2) on St. Vincent, both sexes of the same hummingbird pollinated the flowers of <italic>H. bihai</italic> (species specialization); and (3) on St. Kitts, only females pollinated the flowers of <italic>H. bihai</italic> (sexual specialization), whereas several species of hummingbird visited the flowers of <italic>H. caribaea</italic> (species generalization). We propose that the <italic>Heliconia</italic>–hummingbird interactions in the Eastern Caribbean represent a geographically variable coevolutionary mosaic of plant–pollinator interactions.</p> </abstract>