Fecundidade, dispersão e predação de sementes de Archontophoenix cunninghamiana H. Wendl. & Drude, uma palmeira invasora da Mata Atlântica

Abstract

-(Fecundity, dispersal and predation of seeds of Archontophoenix cunninghamiana H. Wendl. & Drude, an invasive palm in the Atlantic forest). Understanding the basic biology of invasive species can help us to choose the best management strategies to deal with the invasion. I report the phenology, seed production and dispersal of Archontophoenix cunninghamiana, an Australian palm that is invading Atlantic forest fragments. Field work was done in a 10 ha forest fragment (Mata da Cuaso 23º34' S, 46º43' W). Archontophoenix produced bunches of fruits all year round, with a peak of mature fruits from October to February. Trees reach maturity around 18.5 cm DBH, each producing 4,119 ± 1,922 seeds year -1. Birds disperse the seeds, and nearly 15% of them escape post-dispersal seed predation during the time interval needed for germination. The spatial pattern of post-dispersal predation and the absence of pre-dispersal seed predation suggest a lack of specialized seed predators of Archontophoenix, as predicted by the enemy release hypothesis. Data obtained from this and other studies pointed out to a massive increase in seed production of A. cunninghamiana in a few years within the fragment. I suggest that this invasive palm can be taking advantage of the absence of Euterpe edulis Mart., a native palm which has similar biology, and was locally extinct due to human disturbances. Recommendations to control the invasion include the continuous removal of all Archontophoenix larger than 15 cm DBH, and the establishment of a buffer zone free of Archontophoenix around the fragment to decrease propagule pressure.

The exotic palm Roystonea oleracea (Jacq.) O. F. Cook (Arecaceae) on an island within the Atlantic Forest Biome: naturalization and influence on seedling recruitment

“…In addition, some palms are also favored at disturbed sites, where they can flourish (Aguiar & Tabarelli 2010;Andreazzi et al 2012). In view of these factors, problems with invasive palm species are to be expected (Svenning 2002) and have been reported by several authors (Dislich et al 2002;Svenning 2002;Christianini 2006;Meyer et al 2008).…”

The effects of an exotic palm on a native palm during the first demographic stages: contributions to ecological management

“…Within the forests it has invaded, Archontophoenix cunninghamiana fructifies during the same period . Both species are prolific, their fruits are of the same size, and the fruits of both are dispersed by generalist frugivorous birds (Galetti et al 1999;Christianini 2006;. Therefore, it is probable that the niches of A. cunninghamiana and E. edulis overlap to some extent (Dislich 2002).…”

The parakeet Brotogeris tirica feeds on and disperses the fruits of the palm Syagrus romanzoffiana in Southeastern Brazil

“…None of the latter authors mention the possibility that Brotogeris parakeets might disperse palm fruits, especially the larger ones. However, Christianini (2006) states that B. chiriri feeds on the pulp of the exotic palm Archontophoenix cunnighamiana and drops the "seed" under the mother-tree.…”