By Daniel Dickinson
BBC reporter in Dar es Salaam, Tanzania
Hundreds of Tanzanian farmers are jumping on the bandwagon
Haji Mshangama charges across the hilly landscape of the East Usamabara mountains brandishing his blue butterfly net.
Suddenly he snaps the net down and has caught what he is after: a pregnant female Salamis Parhassus butterfly.
This is the beginning of a process lasting up to two weeks which will culminate in the export of the live pupa or chrysalis to a butterfly exhibit somewhere in the US or Europe.
Mr Mshangama is a happy and increasingly rich man, at least by local standards.
Working with seven other farmers, he began farming butterflies just ten months ago. In June his group sold pupae worth $500, a staggering amount of money, in an area where many farmers are earning just one or two dollars a day.
Tempted away from tea
"My friends did think I was a bit crazy when I started farming butterflies," Mr Mshangama says.
"But when they saw how much money I was making they realised it was a good thing to do and they no longer say that.
"Now they all want to farm butterflies."
And so they are: there are now around 250 farmers based in four villages in the East Usamabara mountains who are raising butterflies.
This year they expect to earn around $20,000, and probably more next year.
They have turned their back on some local traditions - cutting timber, poaching, giving up work on the tea estates which dot the hillsides - and transforming themselves from subsistence farmers into small scale cash crop entrepreneurs.
Eggs to riches
Despite the unfamiliar technicalities of butterfly farming, they are getting the hang of things.
The pupae complete their life's journey by bus
East Usamabara farmers are already excelling at producing a wide range of pupae which are as colourful and varied as the butterfly that will finally hatch from them.
The farmers begin by catching a pregnant female butterfly and putting it in a large fly-cage. Once the butterfly lays her eggs on her favourite type of plant, which the farmer has grown from seeds collected in the mountain forest, they are collected and placed in a small canister.
The eggs hatch into caterpillars which are placed in their own cage, where they eat copiously before creating their protective covering which is the pupa.
Spreading their wings
The pupae of many different varieties, some of which can be found only in the East Usamabara mountains, are collected from the individual farmers, put on a bus to the Tanzanian commercial capital, Dar es Salaam.
From here they are sent by courier to live butterfly farms and exhibits overseas.
Only there do they hatch into butterflies.
Asha Ibrahim is one of many farmers who has taken up the challenge of farming butterflies. "It is easy work, a lot easier than other types of farming," she says.
"The important thing is to make sure you do the right thing at the right time."
The butterfly idea was brought to the farmers by Theron Morgan-Brown, a young American biologist.
He spotted the potential of the area, its wide range of butterfly types and the demand for rare African butterflies coming from the increasing number of exhibits around the world.
Tanzania's butterflies flutter in Europe and the US
"In Africa the only commercial exporters of butterflies are in Kenya, South Africa and now Tanzania," he says.
"So these farmers are well placed to do good business."
Theoretically, butterflies can be farmed wherever they are found, although areas rich in bio-diversity are more likely to provide the range of different species wanted by exhibits.
Areas of West Africa, as well as central and southern Africa, could provide yet more species not seen "live" outside Africa before.
As with any commodity, however, the danger is that over-eager production will force down prices, and the business may become less viable.