Nsenene population dying out soon, scientists warn

A man buys nsenene from a vendor in Nakasero Market in Kampala on December 9, 2021. PHOTOS/ISAAC KASAMANI 

What you need to know:

  • To overcome risks of extinction, Prof Philip Nyeko of the Department of Forestry, Biodiversity and Tourism at Makerere University, says his team will test the viability of commercial breeding of nsenene for reliable and predictable yields.

Paul Mubiru’s joyful and brisk vending of nsenene aboard a Uganda Airlines flight on November 26, thrust him and colleague Hajib Kiggundu into harsh glare of public limelight. 
But the untold story of the video clip that has since gone viral was the rush on board by travellers for the rare tablespoon tropical delicacy from sub-Saharan Africa, biologically referred to as Ruspolia differens.

Both Mubiru and Kiggundu, who are importers from the United Arab Emirates, had sensed the huge demand for the nsenene delicacy, especially among Ugandan travellers. 
They seized the chance to make quick bucks, given this season’s low catch. 
In parts of central and western Uganda, the rains inspire swarms of nsenene twice a year. 
But over the years, nsenene have become a seasonal money-spinner as businessmen have invested in trapping the swarms with powerful electric lights or beams and empty oil drums.

Ironically, the increasing demand for the sumptuous snack is being threatened by the dwindling catches in recent years. 
The dropping catches are no longer a secret. Both businessmen and scientists agree that the nsenene population is dwindling and may die out altogether soon.
The drooling consumers, who usually enjoy the delicacy throughout November, are now expressing disappointment via memes on social media. A photo of three human skeletons captioned: ‘Me and my friends at the City Square waiting for nsenene,’ tells it all. 

Meanwhile, the businessmen; the harvesters and hawkers, are even more worried. 
“Honestly, there’s been a steady decline in the nsenene catches for about three years now,” says Abdul Katende, the leader of the nsenene traders based in Katwe, a Kampala City suburb. 
He says the grasshoppers they used to harvest in December used to come from Mubende and Bundibugyo, before those areas started trapping them. Nowadays, they mostly come from as far north as Paidha. 

Then the ones they trapped in September came from Masindi where the rain was sufficient, but did not reach Hoima, meaning there was little to no harvest in Hoima. 
The weather used to be different in the 1990s when Katende joined this business.
He says by then, the rainy seasons could be longer and cover larger parts of the country. 
Nowadays, Masaka, the cradle of nsenene business, reports meagre harvests due to poor rain, which Katende attributes to the decline in the forest cover. 
Mwisho Jiraane, whose affection for senene, as they call them in his native Tanzania, started in childhood, says: “Those insects used to pay most of our school fees.” 
He says: “Papa [dad] used to do it as a part-time hobby but when he died, our uncle partnered with mom and took the business to another level.” 

“They invested in flashlights, empty oil drums and new iron sheets to trap the swarming insects,” he says.
“In a good season, we could collect several sacks and sell to wholesalers, who would sell to retailers,” he adds.
There was also another opportunity for the young ones.
“Some customers could hire us to unpluck the legs and wings at a modest fee.”
But all that has changed over the years because grasshoppers are seasonal, and unpredictable.
In 2010, Jiraane started driving heavy-duty fuel tankers, plying long routes. The second company he joined in 2015 sent him on trips to Uganda via the Mutukula border. 
Eventually, he would find a wife and a home in Mutukula. And when his employers sold off the company, he lost his job.

But the father of two rolled back the years to fall back on his family old job of selling nsenene
With limited resources, Jiraane opted to be hired as nsenene harvester because of his experience.
He would set up trapping sites and monitor them at night and sell the grasshoppers as a retailer. 
“At first, it was challenging because we would work pretty hard, but it was equally rewarding,” he says. 
“Nowadays, due to decreasing harvests, we buy senene very expensively, which means we should also sell expensively and this discourages demand,” he says.

The science 
Prof Philip Nyeko, an associate professor in the Department of Forestry, Biodiversity and Tourism at Makerere University, says grasslands are the ideal habitat for grasshoppers. He says vegetation that does not dry out such as the elephant grass, provide grasshoppers with food.
The grasslands also provide good breeding spaces as the insects lay their eggs in those positions where the leaf meets the stem. 
Unfortunately, the bushlands are dwindling due to increasing urbanisation and agriculture.
But that’s not all. Prof Nyeko cites trapping as another big problem.

He says though no comprehensive study has been done to assess the impact of trapping on the grasshopper populations over time, the current decline in catches cannot be overlooked.
Prof Nyeko says when the young grasshoppers are born, they first live solitary and can be spotted in grasslands, drylands backyards, among other places. Later, they grow and start aggregating, moving in swarms mainly to mate and breed.
Unfortunately, that’s when their biggest predator—humans—take advantage to catch and eat them.

Cutting reproductive cycle
Prof Nyeko says humans eat the potential mothers and fathers, which endangers the rate of continuity. 
Yet we wait to munch the delicacy every season.
“Trapping has intensified in many parts of the country in recent years. In Uganda, there are two swarming seasons in late April to June and October to December, sometimes stretching to January,” he says.
Jiraane says businessmen in Masaka start laying the traps even before the swarming season starts. 
Nyeko says: “That means they are targeting the very first parent stock and the number we remove from the environment is increasing and the stock that remains to reproduce is reducing.”

“Problem, we don’t know the optimal quantity we should remove from the environment,” Prof Nyeko says.
Neither the nsenene dealers nor the scientists know when the nsenene population will die out. 
But both agree that the populations are decreasing at a worrying rate.
When asked what options are open, given the scenario, Jiraane simply answers: “Sijui,” meaning he does not know or is unsure. 
Neither does Katende, and most dealers in the business. But scientists believe they can do something. 

Saving nsenene 
For the last 10 years, Makerere University researchers have been trying to study and demystify the mysterious grasshopper lifestyle in a bid to enable farmers to rear them on large scale and save the insects from extinction. 
Scientists have already made strides in rearing insects such as bees, black soldier flies and worms, which inspires hope in the grasshopper venture. 
Prof Nyeko says they already know the grasshoppers’ staple meal is grains or grass.
“So we get the parent stock from the wild, let them lay eggs in the labs, and rear the young ones into adults, while feeding them on various food stuffs.” 
“We want to make these ones reproduce under local farming conditions,” he adds.

Scientists also know that they need shelter, with a favourable humidity and temperature ranging from 27°C to 29°C, meaning Ugandan farmers may not need to modify the requisite temperatures. 
Prof Nyeko adds that scientists also know that the green grasshoppers lay more eggs than the brown ones. 
But this depends on their diet, so does the size and nutritional composition of the grasshoppers raised under lab conditions. 

Farmbiz Africa reports that Makerere is partnering with Jomo Kenyatta University of Agriculture and Technology in Kenya, which have already established protein content of 37.1 percent and 35.3 percent; fat content of 48.2 percent and 46.2 percent, for the green and brown grasshoppers, respectively. 
Revealing results of the Entomic Research Project, in June, Prof John David Kabasa, the principal of the College of Veterinary Medicine, Animal Resources and Bio-security (COVAB), says they are embarking on establishing greenhouses as habitats for edible insects to breed and enhance efficiency of entomic meat and protein value chain in the African region.

Regulating a mystery 
Katende says the other challenge that makes business even harder is what he called “unrealistic regulation,” 
“Unlike in the past, nowadays, we incur heavy costs, moreover before we are sure of harvesting.” 
“They can charge you over Shs350,000 for electricity, pay the landlord, pay for the trading licence before even the season starts. If the harvest turns out to be low, it threatens business,” Katende says. 
“How do you regulate something whose source you don’t know?” he wonders.

Farming Nsenene

Prof John David Kabasa, the principal of the College of Veterinary Medicine, Animal Resources and Bio-security (COVAB), says there’s need to produce more from grasshoppers than merely frying them for a commercial benefit. 
Similarly, for commercial purposes, Prof Philip Nyeko, an associate professor in the Department of Forestry, Biodiversity and Tourism at Makerere University, says relying on nature makes it an unreliable venture because the yields are seasonal and the numbers are now dwindling. 
Kenyan researchers are also studying the potential medicinal and aphrodisiac properties associated with the nsenene after a high recommendation from the mass consumers in Uganda and Tanzania.

Abdul Katende, the leader of the nsenene traders based in Katwe, a Kampala City suburb, agrees with the scientists that the loss of forest cover and bushlands is endangering the grasshoppers but strongly refutes the claims that indiscriminate harvesting is equally a problem. 
“The ones we trap are the mature ones, ready to be eaten…so what should we do?” Katende asks.

He says he and his colleagues used to sell those grasshoppers to scientists for trials and has little to no hope that these mysterious crickets can be domesticated at commercial level. 
“I want you to try it as well. They will die one by one,” he says, with obvious pessimism. 
“We’ve tried it several times but failed. First and foremost, we don’t know what they eat.” 
But banishing such pessimism, and solving intricate puzzles through rigorous research is what distinguishes scientists from ordinary folk. 

Next year, around May, Prof Nyeko and his colleagues will unveil the project with farmers in Mityana to test the viability of commercial breeding of these mysterious insects, for reliable and predictable yields.
“If a farmer can produce 1,000kg of nsenene in one cycle, that makes business sense,” Prof Nyeko says. 
“But for the start, even 50kg can be promising,” he adds.  
But how much could one need to invest in this venture? 
That’s a bit too early, Prof Nyeko says, adding that the project will provide some basic production kits but the farmers will also have to invest something. 

The fluctuations

At Nakasero Market in central Kampala, a 50kg sack of  live nsenene that costs between Shs600,000 and Shs800,000 last week due to low supply, was costing between Shs200,000 and Shs300,000 on Thursday (December 9). Similarly, a plastic cup of live nsenene that cost between Shs10,000 and Shs20,000 last week was going for between Shs5,000 and Shs7,000. A tablespoonful ranges between Shs1,000 and Shs2,000, depending on turnover and customer. It should be noted that some businessmen say they prefer a lower supply because the competition is lower, hence the prices are higher. 

Dealers prepare to trap nsenene in Masaka District recently. PHOTO/COURTESY


Understanding seasons and life cycle
According to research published in the International Journal of Integrative Biology in 2010, the Ruspolia differens have two overlapping generations (G1 and G2) a year. 
Each generation can last a year. G1 is born April-March and G2 in November-October. 
Eggs which initiate G1 are laid in April-May by the G2 swarming adults. 

The eggs become nymphs and then adults from this time to October, giving rise to the solitary adults, which eventually gives rise to the G1 swarming phase (adults) between mid-November to late-December. 
Most members in the swarms suffer predation particularly by humans, birds, small mammals, among others. 

The few survivors revert to solitary lives in January to mid-February, where most die of senescence or biological aging, marking the end of this generation. 
Meanwhile, the G1 non-swarming adults coexist with enormous bands of nymphs, hatched from the eggs laid by the previous swarming phase (November-December). 
From then, the eggs become nymphs, and between mid-February and mid-April, nymphs become G2 adults, which live solitary lives before aggregating into swarms between mid-April to late May. 

Ruspolia differens swarm in the rainy seasons when food, water, shelter and breeding grounds are abundant. They have a unique character of resorting to solitary lives to avoid competing for scarce resources in dry seasons such as in June to mid-September. Conversely, locusts and Mormon crickets swarm in response to resource scarcity. 


You're all set to enjoy unlimited Prime content.