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Open Ornithology Journal
Number of Followers: 2

This is an Open Access Journal

Open Access journal
ISSN (Online) 1874-4532
Published by Bentham Open

[69 journals]

Bird Diversity in Nensebo Moist Afromontane Forest Fragment, South Eastern
Ethiopia.
- Abstract: Background:Birds are one component of biodiversity. Ethiopia is rich in biodiversity resources. The avian diversity record is far from complete. There is no scientifically documented information on bird species composition and abundance at Nensebo forest. The objective of the study was to assess species composition, relative abundance and distribution of birds at Nensebo forest in southern Ethiopia.Methods:We employed a stratified random sampling technique with our study area stratified into two dominant habitat types: moist Afromontane forest and modified habitat. Within strata, we established 20 transect lines of 1km length and 0.25km width to sample 27.75% of the study area. We used line transect count methods aided by binoculars to estimate avian species diversity and distribution. We employed quantitative biodiversity indices, such as Shannon wiener diversity indexes to compare species diversity among habitat types and two way ANOVA to analyze the effect of season and habitat on bird species richness and abundance.Results:A total of 105 bird species consisting of 1 endemic, 8 near endemic, 1 globally threatened and 9 Palearctic migrants were recorded in Nensebo forest. Species richness and abundance varied between habitat types in Nensebo forest with mean species richness greater in modified habitat (mean= 4.70 ±1.65) as compared to moist Afromontane forest habitat (mean= 3.95 ±4.12, F=94.66
Glucose Concentrations in Closely Related Titmice () Species Linked to
Regional Habitat Differences Across an Avian Hybrid Zone
- Abstract: Aims:We used physiological data, in conjunction with habitat information, to elucidate the interactions between two hybridizing songbirds within a hybrid zone.Background:Hybrid zones are ideal regions to examine a variety of ecological, behavior, and evolutionary processes. In addition to genetics, behavior, and morphology, physiological differences may impact hybrid fitness, genetic introgression, and even the stability of a hybrid zone.Objective:To assess physiological differences in hybridizing species, we investigated selected venous blood analytes in two species of songbirds hybridizing along the Balcones Escarpment in central Texas.Methods:Using a portable blood analyzer, we assayed blood samples from Black-crested Titmouse () and Tufted Titmouse () individuals along a longitudinal transect that included the contact zone. Ecologically, this transect varies from higher elevation semi-arid regions on the Balcones Escarpment (and west across the Edwards Plateau) to lower elevation mesic forests east of the escarpment.Results:As expected, several blood analytes differed with age, sex, and sedative administration; however, we observed relatively increased blood glucose concentrations in Black-crested Titmice, which occupy the semi-arid habitats of west Texas. Furthermore, glucose concentrations were further elevated following rainfall events. Blood glucose concentrations often increase during stressful conditions and or related to changes in diet.Conclusion:We suspect that Black-crested Titmice have relatively increased blood glucose concentrations as a product of living in a semi-arid environment that causes chronic stress from unpredictable food and water resources. The link between rainfall and glucose may be a result of the increased and greater diversity of food availability after rainfall. Although further research is needed, we suspect that habitat differences and associated lack of physiological adaptations may be a limiting factor in westward range expansion in the more aggressive Tufted Titmice.
Description of New American Carduelis/Spinus Bird Species in La Paz
(Bolivia): .
- Abstract: Introduction:South American siskins () are the outcome of regional evolutionary radiation from an extant (or other extinct) species: , a North America siskin, which thrives in Mexico subtropical areas and is parental of one of the three described North American siskin radiations.Methods:Speciation and/or subspeciation of this South American siskin radiation have probably occurred during Pleistocene Epoch. In the present paper, a new species/subspecies akin to is described by genetic and phenotypic parameters: this new species/subspecies was previously considered a subspecies of which thrives further North and is separated about 1,762 km, 1,094 miles, from this described subspecies, .Results:Our genetic study using mt cyt b, phenotypic and behavior observations show that this putative subspecies is either a different species or a subspecies; we have proposed a provisional name for this finch, instead Conclusion:Species definition is movable and controversial, and it is uncertain in South American siskins, which all show a close genetic and phenotypical relationship, which may be still immersed in speciation processes since Pleistocene Epoch.