Transitioning towards sustainable aquaculture: adoption, production, and productivity outcomes of climate-smart feed ingredients among smallholder fish farmers in rural Kenya
Sustainable feeds
DOI:
https://doi.org/10.65869/sar.v5.i1.140Keywords:
Azolla pinnata, Black Soldier fly, Eisenia fetida, feed adoption, Lemna minor, smallholder aquacultureAbstract
The quest for economically viable and ecologically responsible aquafeed ingredients has emerged as one of the most pressing priorities in smallholder aquaculture development across sub-Saharan Africa. The present study investigates the field-scale adoption, production dynamics, and productivity implications of four climate-smart feed ingredients — mosquito fern (Azolla pinnata), black soldier fly larvae (BSFL; Hermetia illucens), duckweed (Lemna minor), and earthworm (Eisenia fetida) — within Kenya's Aquaculture Business Development Programme (ABDP) framework. Data were collected from 297 smallholder farmers across 14 ABDP-implementing counties spanning the Western, Nyanza, Eastern, and Central regions of Kenya, using a structured interview protocol and a descriptive cross-sectional design. The respondent profile was dominated by middle-aged farmers (36–60 years; 78%) and males (73%). A. pinnata emerged as the predominant feed ingredient in terms of both adoption breadth and production volume, with an aggregate output of 292,535 kg valued at USD 343,816. The most consequential productivity gains, however, were attributable to BSFL, whose combined application with farm-made feed elevated fish output per production cycle by 50.00 ± 6.10% — a statistically significant improvement relative to all other treatment combinations (P < 0.05). Collectively, these findings substantiate the agronomic and economic case for integrating climate-smart ingredients into smallholder aquaculture systems in Kenya, while underscoring persistent barriers that continue to constrain the diffusion of duckweed and earthworm-based feeding practices
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