An Avian Biological Gradient Across Tropical Dry Lowland Local Habitats at Playa Venao, Los Santos Province, Panama
There are a myriad of forest types within Panama, varying by elevation, precipitation and other abiotic factors, which hosts a wide variety of native and migratory species in uniquely-structured avian communities. Panama has been well assessed for presence and distribution of its 987 collective avian species (Angehr, 2014). However most studies in Panama have been broad in scope, overlooking the highly specified habitats that are uniquely structured to host a certain range of avifauna communities. The distinctions in community structure of avifauna along a coastal to inland gradient were assessed among three specialized habitats: the Central Pacific coast, partially deforested tropical dry lowland forest edge and the forest on a roadside. All avifauna were identified using systematic radial point counts in six locations within 100m from each other, totaling 120 observation events over a ten day period. It was investigated whether there were significant differences in diversity (Shannon-Wiener Index, Dh), richness (rh) and community composition (Beta diversity, βa) among the three habitats. Diversity was slightly higher among the Pacific coast (Dc= 2.35, p=0.96) and scattered tropical dry lowland forest (Df=2.38, p=0.94) than the roadside location (Dr=2.04, p=0.81). Abundance was comparatively lowest at the Pacific Coast (at=519, p=0.03), higher at the roadside habitat (at=572, p=0.95), and highest at the tropical dry lowland forest edge (at=628, p=0.02). The species exclusivity ratio was notably highest at the Pacific coast (xc=0.29) when compared to the roadside and forest locations (xr=0.18, xf=0.10). Beta diversity by average abundance indicated that there were three distinct communities within the region of study (βa= N = 3.0). Chi square statistical probabilities determined that species richness and diversity were not statistically variable, therefore the null hypothesis was not rejected. These results convey the relevance of localized habitat areas as separate and distinct, in which an immense array of endemic, residential and migratory species occupy a variety of highly specified niches. Recognition of the presence of specialized habitats demonstrates importance of such coastlines and tropical dry lowland forests as a golden zone for high diversity and endemism.
Forest Sciences | Natural Resources and Conservation
Thomas, Abigail, "An Avian Biological Gradient Across Tropical Dry Lowland Local Habitats at Playa Venao, Los Santos Province, Panama" (2015). Independent Study Project (ISP) Collection. 2278.
Panama: Tropical Ecology, Marine Ecosystems, and Biodiversity Conservation