TWO-EDGED SWORD- THE ROLE OF ALIEN INVASIVE Muntingia calabura L. FOR URBAN BIRDS IN JAKARTA Agung Sedayu (a*), M. Isnin Noer (a)
a) Prodi Biologi FMIPA Universitas Negeri Jakarta, Gd Hasjim Asjarie lt 6, Rawamangun Muka, Jakarta Timur, Indonesia
*) asedayu[at]unj.ac.id
Abstract
Muntingia calabura had been introduced from the Americas to many tropical countries, including Indonesia, where it became invasive. In Jakarta this plant invades every possible lot, managed or less managed areas. However, M. calabura provides services for urban biodiversity, including diurnal birds. The relationship between introduced M. calabura and native urban birds may have been an intriguing, as the birds received hypothetically many advantages, including feeds and shelter. On the other hands the birds, especially the frugivorous, enhance the invasiveness of the M.calabura as seed disperser. It is interesting to understand the role of M. calabura to urban bird community across the gradient of urban habitat matrices. We surveyed 68 fruiting trees of M.calabura across Jabodetabek to understand the factor influencing the rate of bird visit in a fruiting M. calabura tree. The relationship of birds visits (species number, number individuals per species) were analyzed against the average value of NDVI as a measure of habitat matrix, vegetative character (canopy size) and generative characters (number of unripe fruits and ripe fruits) using Spearmans correlation. We found that urban birds are indifferent toward urban matrices, meaning they will come to M. calabura trees despite it stands on densely populated residential areas or on loose office areas, based on NDVI. Birds are attracted to generative characters of the trees (number of ripe fruits and ratio of ripe-unripe fruits) compared to vegetative characters (canopy size). This implies that urban bird species are habituated to human made environment and attracted to food source compared to tree as habitat or protection. The relation between M. calabura and urban birds will sustain the establishment of the alien invasive species in urban habitat.
