Date of Award
Master of Science (MS)
Charles A. Ely
Bird utilization of fruit or nectar from trees of six species was observed in three study areas in Chiapas, Mexico. Data recorded included the use made of each species of tree by birds (composition of feeding assemblages and extent of utilization) and the nature of the assemblages themselves (time, duration, method of feeding and interactions within the group). Flowering and fruiting of trees was seasonal, with most flowering occurring at the beginning of the dry season and with fruiting extending into the next wet season. Numbers of resident birds and migrating North American transients increased at the end of the dry season, when fruiting was abundant. Birds tended to enter a tree as individuals or groups of the same species. Most birds fed at the same level and in the same manner as when feeding in non-fruiting trees. Layering of birds within a tree was rarely observed. Feeding activity usually began in the early morning with a peak at 10:00 hr, followed by a midday low that increased again at 16:00 and ended before dark. Cloudy or misty days often showed increased feeding activity throughout the day. Aggressive behavior was rare among birds feeding from fruit and nectar resources because food was generally in large supply.
Copyright 1977 Craig D. Winter
Winter, Craig D., "Food Utilization in Selected Tropical Trees by Frugivorous and Nectarivorous Birds" (1977). Master's Theses. 1694.