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In Australia, Canary Island Date Palms Phoenix canariensis are ubiquitous, widely planted as ornamental trees in private gardens and along streets and seaside promenades. Seeding freely, a single female palm can produce up to 30,000 fleshy drupes annually. Pied Currawongs Strepera graculina, which can swallow several drupes whole in a single feeding event, present as a major vector in the plant’s dispersal. Based on observations of feeding behaviour as well as an examination of resulting regurgitated pellets, this paper discusses critical factors that influence the performance of Pied Currawongs as a vector of palms. Pied Currawongs exhibit drupe selection preferences, which seem related to a drupe’s ripeness and nutritional value, and a feeding behaviour that consists of short bouts of consumption, followed by longer periods of digestion at nearby perches. As increased ripening of the fruit correlates with an increased maturation of the seed, resulting in a higher germination rate, and as repeated use of nearby perches increases the density of regurgitated seeds, such behaviour has implications on the effectiveness of Pied Currawongs as dispersers of Canary Island Date Palms. |
