Cost of fish production can be reduced by replacement of high-priced fishmeal (FM) with insects sourced ingredients. Four months feed experiment was conducted at a fish farm in Baringo County, Kenya to investigate effects of substituting fishmeal (FM) with black soldier fly larvae meal (BSFLM) on survival and growth performance of C. gariepinus under aquaponic system. Three test diets 35% crude protein content (CP) in which FM was substituted by BSFLM at 25%, 50% and 75% were formulated and experimented with commercial diet of 35% CP. Four weeks old C. gariepinus were stocked in 12 tanks at a density of 50 fish/tank and subjected to the diets. Fish were sampled every three weeks; water parameters were sampled weekly and mortality recorded on occurrence. Diet with 50% BSFLM obtained better FCR for formulated diets with no significance (P<0.05) for FCR and survival. Weight gain of control diet (97.07 g) was significant (P<0.05) compared to formulated diets 64.09g, 69.78g and 67.77g for 75%, 50% and 25% of BSFL replacement respectively. Growth performance and survival demonstrated that BSFLM has potential to substitute FM up to 75%. The fish productivity can be improved and feed cost reduced by incorporating fully defatted BSFLM with CP higher than 25.3% used for the diets.

Aquaponics systems integrate aquaculture and hydroponics to create a sustainable method for food production by recycling nutrients. However, nutrient waste management in aquaponics systems remains a challenge, particularly in achieving optimal growth for both fish and plants while minimizing environmental impacts. This study compared the effectiveness of raft and selected medium culture systems in removing waste from a small‐scale aquaponics production system that included leafy vegetable crops ( Brassica oleracea ) and Nile tilapia ( Oreochromis niloticus ). The aquaponics systems comprised of four hydroponics systems: three media based (charcoal, perlite, and pumice) and one raft system in a completely randomized design. The crops were cultivated in the hydroponic units, while O. niloticus fingerlings were reared in the fish tanks for 22 weeks. To compare the various hydroponics systems, growth metrics for the fish (weight and length) and plants growth parameters such as leaf index and biomass, as well as nutrient analysis were monitored and documented. Physicochemical parameters of the culture water were also monitored. Fish grown in the perlite medium had significantly higher mean final length and weight compared to other aquaponics setups in the study ( p < 0.05). Plants grown on pumice had significantly more total biomass than other media ( p < 0.05) and had the highest crude protein (CP) content, while those planted on perlite had the highest crude lipid content ( p < 0.05). The charcoal medium was the most effective, lowering total ammonia nitrogen (TAN) levels by up to 67.1%. Pumice showed the highest total suspended solids (TSSs) retention capacity ( p < 0.05), resulting in a 25.9% drop in TSS levels. The raft system was the least effective at reducing aquaculture nutrient waste. This study demonstrated that the choice of hydroponics media is important in optimizing aquaponics systems for both plant and fish growth.

Between May 2014 and March 2016, 22 groups of Mount Kenya guerezas (Colobus guereza kikuyuensis Lönnberg, 1912) were reintroduced in Karura Forest, Kenya. To assess the success of the reintroduction, we conducted monthly censuses over 8 years (2016–2023). We determined group size and composition of the reintroduced population. During the censuses, we recorded instances of births, deaths (disappearance), dispersal from natal groups, and the habitat types where groups established home ranges. A total of 14 of the reintroduced groups settled along the riverine zones. Over the years, we recorded an annual increase in the number of births and group size, indicating successful adaptation of the reintroduced primates. Coming from a degraded source habitat, the primary cause of death was related to arboreality adaptation (23 %), and only one case of infanticide during a group takeover was recorded. Group fusion was not observed; however, seven groups with more than two adult males began splitting in 2019. By December 2023, 109 births had been recorded, and groups increased to 31 due to natal dispersal. Our results demonstrate that C. guereza kikuyuensis reintroduction to Karura Forest was a success.