Labour intensive grading and transferring larvae between ponds can lead to loss of larvae. For this reason Yalelo's has started testing new live fish transfer and grading technologies. Photo: Opmeer Reports
Zambian company Yalelo Limited is an excellent example of an aquaculture startup that has beaten the odds to become a success.
Established in the world’s biggest man-made lake and reservoir, Lake Kariba, less than four years ago, the 30-million fry facility today boasts sales of 3,000 tons of market-size tilapia.
This feat has been achieved in an environment characterized by limited roads and power, bad to no technical support for equipment and machinery, a talent pool that lacks aquaculture training and a market undermined by low-priced Chinese tilapia byproducts.
Key factors for Yalelo’s strong performance are its management team that maintains passion and perseverance despite many challenges, business organization and human resources approach that prioritizes respect and brings the best out of employees. Other factors include the decision, taken early on, to be self-sufficient in most of its technology, simplify operations and, of course, having nature on their side.
A fish pump, grader and counter have recently been introduced to improve handling and remove the need for human contact with the fry.
Simplicity works best
Establishing its own hatchery early on has been a critical factor in Yalelo’s phenomenal growth. Watson Pasipamire, the hatchery’s manager, is the person responsible for supplying 30 million 3-5g tilapia fry annually. In 2016, that volume will take the company to around 7,000 tons of ready product.
Although producing tilapia fry is simpler than fry of marine species, managing such a large hatchery poses challenges.
Yalelo’s hatchery and nursery covers a five-hectare area and consists of 60 geomembrane-lined earthen ponds divided into broodstock, spawning, larval and nursery sections. The facility’s simplicity clearly reflects the industrial design principle coined in the early 60’s, reportedly by Lockheed engineer Kelly Johnson, “Keep it simple, stupid” (better known by the acronym KISS).
One row of 24 ponds, each around 200 square metres, allows the company enough flexibility to set up spawning groups that will deliver larvae to stock in the 36 larger (0.1ha) ponds. Water is pumped from Lake Kariba, 500m away from the hatchery, and returned to the lake after going through artificial wetlands designed to clean and purify wastewater.
There are a few challenges to the level of control in the ponds such as the high algal growth in tanks that results from the intense sunlight. Also, the water level in Lake Kariba changes constantly because of seasonal rains and the use of water by hydroelectric power stations. This leads to variations in the water pumped to the hatchery.
Solutions to these problems are not complicated although the need to keep it simple may restrict some of the technologies we would consider obvious.
A 60-day cycle
The company opted to use tilapia strains common in Lake Kariba and sourced them from nearby hatcheries. This year it started a genetic selection program to improve the commercialization of some strains. Reducing variability in production and increasing growth and conversion performance are the program’s goals.
At Yalelo’s latitude tilapia spawn almost continuously, and groups of males and females (around 300 at a time) are placed in a spawning tank for two weeks until spawning occurs and eggs can be collected from the mouths of females.
After the eggs hatch the larvae are placed in hapa net cages in the larger nursery ponds until they reach 1.5 grams, at which point they are released into the large ponds for a final 30-day pre-growing to reach the size for transfer to the lake.
Tilapia males grow faster than females as they spend less energy on maturation, and in this species mono-sex populations have better performance than mixed-sex populations (males and females tend to fight a lot). For this reason Yalelo, as most tilapia producers, opts to work with all-male populations.
These populations are achieved by providing larvae and fry during the first three to four weeks feeds with methyl-testosterone until most or all fish become males. Once fish “opt” to become males then this sex is relatively permanent (it’s never easy to achieve 100 per cent males) and ensures good performances in the on-growing stages.
Yalelo’s growout sites require around 300,000 fish to stock each of the cages. Achieving these relatively large batches of fry and ensuring that each batch delivered is genetically uniform and similar in size requires even larger batch sizes from each spawning pond to support two or three rounds of grading.
Producing these large batches also requires substantial handling of the fry, including collecting yolk-sac fry in the breeding ponds, transferring between ponds, gradings, countings, and transporting to the cages. Each of these steps is a cause of stress to the fish and creates an opportunity for pathogens to attack and kill weakened fish.
To minimize the physical stress on fish, Yalelo recently acquired a fish pump, automatic grader and a fish counter. The company also acquired an amphibious transport vessel that reduces the number of steps in the transfer of fry from the nursery to the cages.
The impact from these new technologies is already visible in the reduced stress and mortality of fry after stocking, and I am sure this will prove critical for the company to continue its growth trajectory.
Yalelo has shown that the challenges of starting a fish farming project in a Sub-Saharan African country can be turned into advantages and that a good strategy, well adapted to the company’s environment, a good team and perseverance can deliver growth that is unusual in Western fish farming businesses.
The realization of the importance of a good, well-performing hatchery and that fry quality – genetics, nutrition and health – is a key determinant of growout success is, in my view, one of the most important components of Yalelo’s business plan and will prove itself as the growth engine for this project.
— Diogo Thomaz
Diogo Thomaz, PhD, MBA, is a Technical and Business Consultant for the Aquaculture Industry, based in Athens, Greece. After 15 years as R&D project manager and other industry positions he now leads Aquanetix (www.aquanetix.co.uk), a data management and reporting service for the global aquaculture industry. He also heads RealSales Ltd (www.realsales.eu) a sales consultancy company that helps businesses expand their opportunities in export markets. He can be contacted by email on email@example.com