[Ecology • 2017] Nectar Properties and the Role of Sunbirds as Pollinators of the Golden-flowered Tea (Camellia petelotii)

 a sunbird (Aethopyga siparaja) pollinating a flower of Camellia petelotii; note contact of the pollen-bearing beak with stigmas

@Botanical_    DOI: 10.3732/ajb.1600428 

ABSTRACT

PREMISE OF THE STUDY: Properties of floral nectar have been used to predict if a plant species is pollinated by birds. To see whether winter-flowering plants evolve nectar properties corresponding to bird pollinators, nectar properties of several Camellia species (including the golden-flowered tea), as well as the role of floral visitors as effective pollinators, were examined.

METHODS: Potential pollinators of Camellia petelotii were identified at different times of day and under various weather conditions. A bird exclusion experiment was used to compare the pollination effectiveness of birds and insects. Nectar sugar components (fructose, glucose, and sucrose) from C. petelotii growing wild and another seven Camellia species and 22 additional cultivars (all in cultivation) were examined by high-performance liquid chromatography (HPLC).

KEY RESULTS: The sunbird Aethopyga siparaja and honeybees were the most frequent floral visitors to C. petelotii. Honeybee visits were significantly reduced in cloudy/rainy weather. The fruit and seed set of flowers with birds excluded were reduced by 64%, indicating that bird pollination is significant. For the wild populations of C. petelotii, a bagged flower could secrete 157 μL nectar; this nectar has a low sugar concentration (19%) and is sucrose-dominant (87%). The eight Camellia species and 22 cultivars had an average sugar concentration of around 30% and a sucrose concentration of 80%, demonstrating sucrose-dominant nectar in Camellia species.

CONCLUSIONS: The nectar sugar composition of Camellia species was characterized by sucrose dominance. In addition, the large reduction in seed set when birds are excluded in the golden-flowered tea also supports the suggestion that these winter-flowering plants may have evolved with birds as significant pollinators.

Key words:  bird pollination, Camellia petelotii, effective pollinators, insect pollination, nectar properties, sucrose content, Theaceae, winter flowering

Shi-Guo Sun, Zhi-Huan Huang, Zhi-Bao Chen and Shuang-Quan Huang. 2017. Nectar Properties and the Role of Sunbirds as Pollinators of the Golden-flowered Tea (Camellia petelotii).  American Journal of Botany.   DOI: 10.3732/ajb.1600428

Nectar properties & the role of #sunbirds as pollinators of the golden-flowered tea http://www.amjbot.org/content/early/2017/03/15/ajb.1600428.abstract … #botany #pollination #AmJBot @Botanical_   

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[Ornithology • 2016] Cinnyris whytei • A New Member of the Greater Double-collared Sunbird Complex (Passeriformes: Nectariniidae) from the Eastern Arc Mountains of Africa

Cinnyris whytei skye 

Bowie, Fjeldså, Kiure & Kristensen, 2016

  DOI: 10.11646/zootaxa.4175.1.3  

Abstract

We document the discovery of the first population of greater double-collared sunbird (Cinnyris afer complex) from the Eastern Arc Mountains of Tanzania. We assessed phylogenetic relationships and taxonomic rank based on mtDNA sequence data, nine microsatellite loci and morphology. This new taxon, locally distributed in the Rubeho and Udzungwa Highlands, has close affinities (< 1% uncorrected sequence divergence) with Cinnyris whytei (split here from C. ludovicensis) of the Nyika Plateau in Malawi, but differs in having longer tarsi and in subtle plumage details. Although the birds from Nyika and Udzungwa-Rubeho are reciprocally monophyletic for mitochondrial DNA, coalescent analyses of the microsatellite data and the total molecular dataset could not reject the possibility of continued gene flow between the two populations. Thus, although we favour the phylogenetic species concept, we adopt a cautious approach and formally describe the Rubeho and Udzungwa greater double-collared sunbird population as a subspecies of Cinnyris whytei. This new sunbird taxon has been recorded only above 1700 m in scrub on the forest/grassland ecotone in a very restricted area in the Rubeho and Udzungwa Highlands of Tanzania. The effects of human settlement and agriculture threaten this taxon.

Keywords: Aves, Rubeho, Udzungwa, Tanzania, biodiversity hotspot, microsatellite loci

Cinnyris whytei, species nov.

Cinnyris whytei skye, subspecies nov.

Bowie, Rauri C. k., Jon Fjeldså, Jacob Kiure and Jan B. Kristensen. 2016. A New Member of the Greater Double-collared Sunbird Complex (Passeriformes: Nectariniidae) from the Eastern Arc Mountains of Africa. Zootaxa. 4175(1); 23–42.  DOI: 10.11646/zootaxa.4175.1.3

ResearchGate.net/publication/309024924_A_new_member_of_the_greater_double-collared_sunbird_complex_Passeriformes_Nectariniidae_from_the_Eastern_Arc_Mountains_of_Africa