Spatial Variation in Distribution of Avian Guilds in Response to Plant Species Composition, Habitat Structure and Land use in the Harena Forest of the Bale Mountains National Park, South Eastern Ethiopia
An avian bird community in a forest was classified in to guilds apriori with the objective of determining whether species in the community are clustered naturally in response to bottom processes that have significant direct and indirect effects on birds at various levels of ecological organization. The Harena forest had five habitat categories resulted from spatial variations in collective abundance construct of woody plant species. The constraining effect of this division of the forest in habitat quality was the bird community there was found to have 9 guilds classified according to their adaptive traits which resulted in their matching niche occupancy in the forest with segregations as determined apriori. The number of habitat types occupied by the 9 guilds reflected or was equivalent to the number of habitat types determined from the collective abundance construct of woody plant species. The total numerical response of the community as demonstrated by the significant differentiation of the collective abundance construct of the community in accordance to guild membership indicates the bird community as a whole interacts with habitat quality determinates which indicated the bird community collectively affects habitat attributes of this forest ecosystem as much as it is affected by them. Furthermore niche overlap and the consequent interspecific completion were significantly higher within each guild than amongst guilds. The conclusion that is drawn from the use of data from a real field scenario is the structuring of a bird community in to guilds is a real natural phenomenon and the results proved birds in groups interact with bottom biotic components with effects on their modes of existence which is a prerequisite process determining the manner of coexistence amongst birds too.
