Rainbow Trout
Oncorhynchus mykiss
Rainbow trout is a cold-water salmonid native to Pacific drainages of North America, introduced to Kenya's highlands in the early 20th century and now the basis of Kenya's small commercial trout industry.
Species
Fish
Family
Salmonidae
Climate requirements
Needs clean, cold, fast-flowing water between roughly 10-18C, restricting farming to high-altitude forest-stream areas such as the Aberdares, Mount Kenya, and Mau slopes (Nyandarua, Nyeri, Meru counties).
Husbandry guide
Grown in concrete or earthen raceways and flow-through ponds fed by diverted streams rather than static ponds, since continuous high-oxygen flow is essential. Grow-out stocking is roughly 20-30 fish per cubic meter; overcrowding sharply hurts feed conversion. Feed high-protein (40%+) floating pellets, with feed conversion ratios around 1.2-1.5:1 achievable under good raceway management. Fish are graded regularly and reach about 30-40cm (roughly 0.3-1.5kg) marketable size in 9-24 months depending on system intensity. Prolonged droughts reducing stream flow are an increasing operational risk for existing farms.
Economic importance
Trout is a premium, low-volume product fetching a price well above tilapia or catfish, serving hotels, restaurants, and tourism markets near Nyandarua and Mount Kenya; high water and capital requirements keep it a niche rather than mainstream smallholder enterprise.