The coastal forest of Mafia island has a number of indigenous and exotic flora and fauna species retained in the area. This study was carried to survey existing flora and fauna in the Mlola and Juani coastal forests in Mafia Island. A total of 30 sample plots were established, 25 in Mlola forest and the remaining 5 plots in Juani forest reserve. Seven transects were established in total, 4 in Mlola and 3 in Juani forest. In each plot plant species were indentified and recorded, whereas in each transect birds and insect species were identified and recorded. A total of 75 plant species and 92 animal species (39 birds and 53 insects) species were identified, The plant species identified belonged to 34 different families, of which the family Sapindaceae was more common with 8 species, then followed by Euphobiaceae (7 species), Ebenaceae (5 species), Fabaceae (5 species), Rubiaceae (5 species), Anacardiaceae (4 species), Annonaceae (4 species), Celastraceae (3 species), Tiliaceae (2 species), Moraceae (2 species), Bombacaceae (2 species), Rutaceae (2 species) Burseraceae (2 species) and the remaining families had one specie each. The 39 birds species belonged to 26 different families in which the families Columbidae, Cuculidae, and Nectariniidae were more common having 4 different species each followed by Turdidae, Pycnonotidae, Platysteiridae, Malaconotidae, Coraciidae, and Capitonidae with 2 different species each, the remaining 17 families had one species in each. The 53 insects species belonged to 21 different families in which the families Pieridae, Formicidae, Papilionidae, Nymphalidae, Blaberidae, Lycaenidae, Acrididae, Anthopioridae, Tabanidae, Thespidae, were more common having 9, 7, 6, 6, 3, 3 and 2 different species in the last families respectively, the remaining 10 families had one type of specie each. Diversity indices for flora and fauna (birds and insects) species involved Simpson's indices and the values were 0.0763, 0.0995 and 0.0245 respectively. Shannon Wiener diversity index for flora and fauna (birds and insects) species in Mafia Island FR was 3.0525, 3.4201, and 3.8259 respectively. Furthermore, fauna species (birds and insects) were categorized under IUCN red list whereby none of fauna species was instituted as endangered or near extinction but to a certain extent Vulnerable. The study recommends avoiding or mitigating all the activities that may reduce diversity of flora and fauna species in Mafia Island coastal forests.
We sincerely acknowledge financial assistance from Rufford Small grants Foundation (RSG) whose funding enabled accomplishment of this task. We are also indebted to research members i.e., Mr. Godgift Swai, Mr. Deo Shirima from Sokoine University of Agriculture (SUA) and Mr. Makero Joseph from Forestry Training Institute (FTI). We also thank Mr. Yahaya Abeid for carrying out botanical identification and Mr Victor Kaaya for birds and insects identification. Many thanks are also given to Mr. Hamidu Seki, Mr. Johnson Emanuel and Miss Olrik Baldwina for participating in data collection. We are also indebted to Forest office in Mafia Island Mr Gideon Zakayo for effective coordination of our work in Mafia Island, local botanist and village assistant in Mafia Island as well. We also give much appreciation to the management of the Tanzania coastal forests for permitting operation of this study in Mafia.