Abstract:
This study presents the diversity of terrestrial small mammals and prevalence of
haemopathogens in Mafia Islands and the small islands (Chole, Jibondo, Juani and
Shungimbili) which are associated with Mafia. Terrestrial small mammals comprise a group
of mammals including volant and non-volant which are cosmopolitan and successful due to
their wide range of feeding, adaptive reproduction strategies and habitat occupation. A study
on the diversity of small mammals and their haemopathogens prevalence was conducted in
Mafia Island and small islands associated with it from August to October 2021. A total of 120
rodents were captured by direct method using Sherman traps and indirectly using camera
traps. Each directly trapped individual was immobilized with ethanol and parameters such as
weight and sex were recorded. The samples that were taken include an earpiece which was
preserved in Eppendorf tube containing 90% ethanol for further confirmatory species
identification using molecular techniques. For the purpose of molecularly identifying the
hemopathogens, 0.5 ml of blood was collected from the retro-orbital sinus using a capillary
tube and kept as a dried blood spot on filter paper (Whatman paper). According to the
findings, all of the collected rodents were classified as Rattus rattus and belonged to the RrC
lineage I. One Crocidura hildegardae shrew was also trapped.Our camera traps recorded
black and rufous sengi Rhynchocyon petersi, blue monkey Cercopithecus mitis, blue duiker
Cephalophus monticola, the introduced Small Indian Genet Viverricula indica, and the red
bush squirrel Paraxerus palliatus. Of the 120 Rattus rattus, 13.33% tested positive for
Bartonella DNA. Prevalence between the six studied sites was significantly different (df = 5
and p-value <0.001). None of the rickettsia, leptospira, brucella, anaplasma, coxiella and
trypanosoma was detected. Despite the limited time of data collection, our results show that
there is low diversity of small mammals on the Mafia islands, with R. rattus dominating in all
small islands. Also, the results show the presence of Uncultured Bartonella spp among other
haemopathogen being obtained in R. rattus. The study recommends further studies in the
rest of forest patches in Mafia and to also explore the diversity of flying mammals which was
not included in this study but also to explore more on the prevalence of haemopathogens
within the island.
Key Words: Diversity, Small mammals, Rattus rattus, Haemopathogens, Bartonella, Mafia
