Table 1. Presence and dispersers of bird-dispersed tree species and their seeds on Guam and Saipan.
Family | Species | Bird species seen consuming fruit1 | Guam | Saipan | ||||
Site 1 | Site 2 | Site 3 | Site 1 | Site 2 | Site 3 | |||
Euphorbiaceae | Melanolepis multiglandulosa | BRWE, WTGD, GOWE, MFD, MIST | Traps | Both | * | Both | ||
Verbenaceae | Premna obtusifolia | WTGD, BRWE, GOWE, MFD, MACR, MIST | Both | Both, Fruit | Both, Fruit | Both | Traps | Both |
Rubiaceae | Psychotria mariana | GOWE2 | Traps | Traps | Both | Traps | Traps |
Disperser identity is based on bird observations reported in Craig [95] and Jenkins [96]. No tree species were present in intact karst forest survey transects but not in seed trap contents. A tree species that was present in both intact karst forest survey and in seed trap contents is indicated below by ‘Both’. ‘Traps’ indicates a tree species was present in seed trap contents, but was not present in intact karst forest surveys. ‘Fruit’ indicates that the species was seen fruiting during the forest surveys; if a species was found in seed traps (‘Both’ or ‘Traps’), we also assume that it fruited during the study.
MFD = Mariana Fruit-dove, WTGD = White-throated Ground-dove, BRWE = Bridled White-eye, GOWE = Golden White-eye, MACR = Mariana Crow, MIST = Micronesian Starling. We lack information on fruit in the diet of the Guam Rail.
Other bird species likely disperse Psychotria mariana, but systematic observations of fruiting trees have not been conducted.