Fishing in Rwanda

Lessons

Senior 4 · Geography

Fishing in Rwanda

4 lessons

Lesson 3 of 4

Fish Farming: Factors, Problems and Prospects

25 min

From 500 tonnes to a target of 80,000

Fish farming in Rwanda is old (small ponds have existed for over seventy years) but small. In 2021 it produced about 4,900 t, 17% of the country's fish; MINAGRI's National Aquaculture Strategy aims for about 80,620 t by 2035, three-quarters of all fish produced (MINAGRI, 2023). Figure 3 puts the past and the target side by side.

Figure 3. Farmed fish production and the 2035 target. Drawn by Ganzaa from MINAGRI and RAB (2023).

The 2035 bar is sixteen times the 2021 bar. As you read, collect the factors that could make that possible and the problems that could stop it.

Definition

Fish farming (aquaculture): rearing fish under human control from young fish to market size. Fingerling: a young fish, a few centimetres long, used to stock ponds and cages. Hatchery: a farm that breeds fish and produces fingerlings.

Cage culture: fish kept in floating net enclosures in a lake or reservoir, fed with prepared feed. Pond culture: fish kept in earthen ponds, usually dug at the edge of valley floors, fed partly by fertilising the water. Intensive farming uses many fish per cubic metre and bought feed; extensive farming uses few fish and natural food.

Two systems

	Cage culture	Pond culture
Where	Lakes Kivu, Muhazi, Ruhondo and Sake; some reservoirs. In 2019 there were 26 large cage investors: 12 on Kivu, 10 on Muhazi, 3 on Ruhondo and 1 on Sake (MINAGRI, 2019)	Edges of valley floors, mostly in the Eastern Province near rice irrigation dams, then the Southern Province, where water is warmer (MINAGRI, 2023)
Scale	Medium and large companies; intensive, with bought fingerlings and feed	Single owners, groups and cooperatives; extensive to semi-intensive
Numbers	211 cages on Kivu and 131 on Muhazi in January 2020 (MINAGRI, 2020)	1,087 fish ponds in January 2020 (MINAGRI, 2020)
Share of output	55% in 2021	45% in 2021; about 11,000 t (13–14%) of the 2035 target
Species	Nile tilapia	Nile tilapia; African catfish growing in popularity; carp

Sources: MINAGRI (2019, 2020); MINAGRI and RAB (2023).

Factors favouring fish farming

Water. Lakes, more than 15 hydropower and irrigation dams, valley tanks and deep river pools offer sites for cages and ponds (MINAGRI, 2023).
A climate "generally favourable" for aquaculture, with two rainy seasons to fill ponds; warm water in the east and south and in Lake Kivu (23–26 °C).
Demand. Rwanda imports about 19,000 t of fish a year and aims to raise consumption towards 10 kg per person (MINAGRI, 2023).
Government support. Licensing has been made easier; investors get help with lake concessions, water-use permits and feed import permits (MINAGRI, 2019). In 2024–25, 1,737 fish farmers were trained in good aquaculture practice (MINAGRI, 2025).
Hatcheries. Six hatcheries produced 71.7 million fingerlings in 2024–25 (Figure 4).
Research. RAB has tested black soldier fly larvae as a cheaper substitute for imported fish meal in tilapia feed (MINAGRI, 2025).

Figure 4. Fingerling production by hatchery, 2024–25. Drawn by Ganzaa from MINAGRI (2025). The top three hatcheries produced 82.4% of the total.

Worked example 1: how fast must fish farming grow?

The average annual growth rate $r$ between two values is found from $P_{\text{end}} = P_{\text{start}}(1 + r)^n$ :

r = \left( \frac{P_{\text{end}}}{P_{\text{start}}} \right)^{\frac{1}{n}} - 1

2012 to 2021 ( $n = 9$ ): $r = \left( \frac{4\,900}{500} \right)^{\frac{1}{9}} - 1 = 9.8^{0.111} - 1 = 0.289$ , about 28.9% a year.

2021 to 2035 ( $n = 14$ ): $r = \left( \frac{80\,620}{4\,900} \right)^{\frac{1}{14}} - 1 = 16.45^{0.0714} - 1 = 0.221$ , about 22.1% a year.

Interpretation. The target needs growth only a little slower than the past decade's, but sustained for 14 years from a much bigger base: an extra 75,700 t, compared with 4,400 t added from 2012 to 2021. Growth on that scale needs large cage farms, hatcheries and feed mills, which is why the strategy expects companies producing over 2,000 t a year to be the mainstay (MINAGRI, 2023).

Worked example 2: are fingerlings still the bottleneck?

Data and assumptions. Fingerlings produced in 2024–25: 71,661,465 (MINAGRI, 2025). Assume, for illustration, that 80% survive to harvest at 0.4 kg each.

71\,661\,465 \times 0.80 \times 0.4\ \text{kg} = 22\,931\,669\ \text{kg} \approx 22\,900\ \text{t}

Interpretation. On these assumptions the hatcheries could already stock farms for well over four times the 2021 farmed output. Fingerling supply has improved, so the limits now lie more in feed, survival, growth in cool water and costs. (Real survival and harvest weights vary; change the assumptions and the answer changes.)

Problems of fish farming

Problem	Evidence	Possible solution
Cool water at high altitude	Most of Rwanda lies at 1,300–2,000 m; temperatures are "sub-optimal" for Nile tilapia (MINAGRI, 2023)	Farm in warmer lakes and the low east and south; cold-tolerant strains; carp and, in uplands, possibly trout
Feed and fingerlings	Shortage of quality feed at competitive prices; fingerling output concentrated in a few hatcheries	Local feed mills; insect-based feed; more satellite hatcheries
High costs and cheap imports	Tilapia retailed at about US$4.37 per kg against US$1.60 for imported frozen tilapia from China, $\frac{4.37}{1.60} \approx 2.7$ times dearer (MINAGRI, 2023)	Cut costs through good management; sell fresh, local quality
Limited skills	"Limited skills and capability" named as a major hurdle (MINAGRI, 2023)	Training (1,737 farmers in 2024–25), extension services
Silted water, environmental risk	Silted rivers make some sites unsuitable; Lake Kivu carries a risk of gas release; introduced species threaten biodiversity (MINAGRI, 2023)	Zoning and spatial planning, environmental impact assessment, catchment protection
Seasonal dips	Harvests fell from 14,999,895 kg in Q3 to 9,977,292 kg in Q4 of 2024–25 (MINAGRI, 2025)	Stagger stocking; cold storage

Prospects

The strategy foresees about 80,620 t of farmed fish by 2035, mostly from large cage farms, with ponds still important for youth and women because their inputs are cheaper; diversification into catfish and carp; cold-chain investment; and a rise in fish consumption towards 10 kg per person a year (MINAGRI, 2023).

Warning

Not all fish production is farmed. MINAGRI's 52,439 t for 2024–25 includes fish from lakes and rivers as well as cages and ponds. When you quote a figure, say whether it is total production or aquaculture only, and give the year.

Rwanda Agri, 2020 (in Kinyarwanda): "Uko ubworozi bw'amafi muri kareremba bukorwa", how fish are farmed in cages on Lake Kivu. Watch how the floating cages are built and managed, and list the inputs the farmers need.

✦

Practice

Distinguish cage culture from pond culture in Rwanda.
Name four lakes with large cage farms and explain why lakes suit cages better than shallow ponds for large companies.
Using Figure 4, what percentage of fingerlings came from the two Rwamagana hatcheries?
Calculate the average annual growth of farmed fish output from 1,600 t in 2016 to 4,900 t in 2021.
Give four factors favouring fish farming in Rwanda, with evidence.
Explain why imported frozen tilapia is a problem for Rwandan fish farmers.
"Large companies, not small ponds, are the future of Rwandan fish farming." Discuss.

Show answersHide answers

Cage culture: floating net enclosures in lakes (Kivu, Muhazi), intensive, company-run, fed with bought feed (55% of output in 2021). Pond culture: earthen ponds at valley edges, mainly in the east and south, extensive to semi-intensive, family or cooperative (45%).
Kivu, Muhazi, Ruhondo, Sake. Lakes give large volumes of well-oxygenated water that is exchanged naturally through the nets, so many fish can be held without digging land.
$\frac{11\,887\,750 + 9\,629\,895}{71\,661\,465} \times 100 = 30.0\%$ .
$\left( \frac{4\,900}{1\,600} \right)^{\frac{1}{5}} - 1 = 0.251$ , about 25.1% a year.
Water (lakes, dams, valley tanks); warm water in the east, south and Kivu; demand (19,000 t imported); government support (easier licences, 1,737 farmers trained); hatcheries (71.7 million fingerlings); research on cheaper feed.
It sold at about US$1.60 per kg against about US$4.37 for local tilapia, so buyers may choose imports, cutting local farmers' sales unless they reduce costs.
For: the strategy expects large cage farms (over 2,000 t a year) to supply most of the 80,620 t target; they can afford feed, hatcheries and cold chains. Against: ponds need cheap inputs, employ youth and women and spread income in rural areas; the strategy still expects about 11,000 t from ponds. Both are needed: companies for volume, ponds for livelihoods.

Quick check

Match each term to its meaning.

Tap one on the left, then its partner on the right.

Key points

Farmed fish: about 500 t (2012), 1,600 t (2016), 4,900 t (2021); target about 80,620 t by 2035, needing about 22% growth a year.
Cage culture on Kivu, Muhazi, Ruhondo and Sake (55% in 2021); ponds mainly in the east and south (45%). Tilapia dominates; catfish and carp are growing.
Favouring: water, warm sites, demand and imports, easier licensing, training, 71.7 million fingerlings (2024–25), feed research.
Problems: cool water at altitude, feed costs, cheap imports (US$1.60 against US$4.37 per kg), skills, silt and environmental risk. Prospects: big cage farms, diversification, cold chain.

Sources and credits

Sources: National Aquaculture Strategy for Rwanda, MINAGRI and RAB, 2023 (production 2012–2021, target, systems, factors, problems, prices, prospects); Annual Report 2024–2025, MINAGRI, 2025 (fingerlings by hatchery, quarterly harvests, training, black soldier fly trial); Enhanced farming practices boost fish production in Rwanda, MINAGRI, 2019 (cage investors, licensing support); Stakeholders discuss ways to streamline fish production in Rwanda, MINAGRI, January 2020 (numbers of cages and ponds).

Figures 3 and 4, the tables and the worked examples were drawn and written by Ganzaa.

Photo: Lake Muhazi part of Rwamagana, UWIMPUHWE Va, CC BY 4.0, via Wikimedia Commons.

Video: "Uko ubworozi bw'amafi muri Kareremba bukorwa | Fish farming in cages on Lake Kivu", Rwanda Agri, embedded from YouTube. The rest of the lesson and the exercises were written by Ganzaa.

1From 500 tonnes to a target of 80,000

2Two systems

3Factors favouring fish farming

4Problems of fish farming

5Prospects

From 500 tonnes to a target of 80,000

Two systems

Factors favouring fish farming

Problems of fish farming

Prospects