Abstract

In the early 20th Century, Guibourtia copallifera Benn. was extensively exploited as a source of gum copal.  Its geographic distribution in Sierra Leone is now restricted to a few square kilometers in a single badly degraded forest reserve. We conducted a series of seed rain experiments to quantify its seed dispersal potential. Transects of seed traps were laid out and a total of 1,164,880 seeds were collected over the two months when G. copallifera sheds its? seeds. Seeds from a further 85 species were collected. The majority of species were wind dispersed followed by terrestrial animals, bats and birds. Leguminosae-Caesalpiniaceae had the highest number of species, followed by Euphorbiaceae, Apocynaceae, Rubiaceae and Sterculiaceae. There is no statistically significant difference between the transects (p>0.05, df=79, F=0.023) or the types of traps (p>0.05, df=118, t=0.089). Median dispersal distances of G. copallifera seeds was 41.22 m from the forest edge. The reserve still possesses a high natural regeneration potential for G. copallifera but increasing human disturbance is opening the canopy allowing pioneering species to dominate and reducing the ability of G. copallifera seedlings to establish.

Key words: Guibourtia copallifera, seed rain, seed dispersal, forest reserve, Sierra Leone.