Information on nesting behaviour, productivity in natural tree cavities and man-made hives and natural enemies of resident stinging honeybee sub-species was gathered for a period of 1 year in Udzungwa Mountains National Park, Tanzania. Three sub-species of the honeybee Apis mellifera occur in this area. Six types of hive were sited in appropriate locations and colony dynamics studied. The bees also nested in tree cavities facing east and west, and also in most types of hive, with the exception of burnt brick ground level 'Chikka' hives. There were few natural enemies of bees in the area. The density of honeybee colonies per hectare, occupancy of various types of hive and quantity of honey and beeswax harvested from various types of hive all favoured beekeeping in this area. Development of apiculture in the area and its role in conservation of the Udzungwa ecosystem are discussed.

Resident stingless honey-bees in the Udzungwa area were investigated for a period of 1 year. Specimens of stingless honey-bees were captured on flowers and on natural nest entrances. Six local stingless honey-bee species, namely Dactylurina schmidti, Plebeina hildebrandti, Axestotrigona erythra, Meliponula ogouensis, M. lendliana and M. ferruginea, were found in the area, all of which are known to the local people. Honey productivity per colony in experimental hives varied according to species: M. ogouensis average 3.2 L, M. lendliana average 2.7 L, D. schmidti average 1.6 L and P. hildebrandti average 0.6 L. These findings indicate good potential for beekeeping in the lower altitude area at the foot of the Udzungwa Mountains, where the stingless honey-bee species diversity is greatest. The article discusses some options for intensification of management of the bee resources while maintaining natural biodiversity in the area.

Prawns are commercially one of the most important marine resources. However, in their early developmental stages, they face challenges related to physico-chemical and environmental changes. This study aimed at investigating the effects of temperature and salinity on egg incubation time, hatching success, larval and postlarval survival of the giant tiger prawn, Penaeus monodon (Fabricius 1798) obtained from the coastal waters of Tanzania. The adult females P. monodon collected off Rufiji delta were left to acclimatize and spawn at 28.5 ± 0.5 °C and 32 ppt in the hatchery. Spawned eggs were incubated at experimental temperatures of 27 °C, 31 °C and 35 °C with three subgroups of salinities of 30 ppt, 35 ppt and 40 ppt. The incubation time was longest (15.2 hours) at 27 °C and 30 ppt, and shortest (10.7 hours) at 35 °C and 40 ppt. Hatching success was highest (85.2%) at 31 °C temperature and 30 ppt salinity, and lowest (69.45%) at 35 °C and 40 ppt. Larval and postlarval survival was suitable at 27–31 °C and 30–35 ppt. These findings suggest that optimum rearing temperature and salinity for P. monodon range 27–31 °C and 30–35 ppt, respectively. Changes in temperature and salinity above the optimum range may jeopardize the hatching and subsequent survival of P. monodon especially at their early developmental stages which are more sensitive to environmental changes. Keywords:    Penaeus monodon, Temperature, Salinity, Incubation time, Hatching success, Survival rate.

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