Avian Utilization of the Fruits of Carissa Edulis Vahl and Jasminum Dichotomum Vahl in A Central Nigerian Reserve

Abstract

This study determined the avian fruit utilizers of the plants Carissa edulis and Jasminium dichotomum both related in the colour and size of their fruits. Furthermore, the study also compared the two plant species in terms of the diversity of avian fruit utilizers, their frequency and duration of visits and activities performed during visits to the plant species. Data was collected in the Amurum Forest Reserve, north central Nigeria, between June and July 2011 through focal observations. A total of 107 individual birds comprising 22 species were recorded during the study. C. edulis had the highest diversity and abundance of bird species as compared to J. dichotomum. Seven bird species were exclusively found on C. edulis while 5 bird species were exclusive to J. dichotomum. The Common bulbul (Pycnonotus barbatus) and Speckled mousebird (Colius stratus) were the most common bird species observed on the two plants. Mean time spent foraging differed significantly across bird species foraging on C. edulis but not on J. dichotomum with the Western grey plantain-eater (Crinifer piscator) spending the highest time foraging on the former. Activities performed by bird species on the two study plants include foraging and perching which did not differ significantly between plants. These observations highlights the ecological importance of the two plants within the reserve particularly in enhancing the survival of other animal groups within the reserve.

Keywords: Carissa edulis, Jasminum dichotomum, Bird species, Fruit, Frugivores.