“So many people who were earning a lot of money from the tourism industry have lost their revenue, so the only option they are left with is poaching bushmeat, to eat but also to sell,” he said.

Those feeling the pinch include the Rhino Fund Uganda, which runs a breeding programme seeking to re-establish a wild rhino population that was wiped out by 1983.

Ninety per cent of the project’s revenue comes from tourism. So when the government introduced a total lockdown on March 25, the impact on the fund and local community was immediate, said Angie Genade, the executive director of the RFU.

“All the buying power in our little village here stopped. Within the first week we had small game poachers inside the fence,” going after warthog and gazelle, she said. "It is a really bad ripple effect."

“Will it lead to rhino poaching? It depends how long this thing goes on and how badly off they are.”

But she fears that if the revenue collapse forces her to cut back on security, the chances of poaching syndicates interested in killing rhinos for their horn will hit “100 percent.”

The RFU’s 30 southern white rhinos are protected by a man-power intensive surveillance operation that sees rangers literally following the animals around the sanctuary and radioing in hourly sit-reps 24 hour hours a day, 365 days a year.

The project has already laid off a third of its staff, and Ms Genade says she can only pay and feed the remaining 98 people, who are confined to the sanctuary under Uganda’s strict lockdown rules, only until the end of April.

She has launched an appeal to members of the public for donations to keep the operation afloat.

The impact varies from country to country. In South Africa wildlife agencies have been classed as essential services during the country's shutdown, and funding ring fenced.

In Zimbabwe, which is already grappling with a dire economic crisis, they receive no direct state funding and are almost entirely reliant on tourism revenue.

With global travel unlikely to recover in the near future, the down turn will present a long-term challenge to one of the fundamental planks of contemporary conservation.

"In the past we have had for example periods of political violence with a year or two without tourism. The game changer here is this is affecting every other sector, not just tourism. You are basically saying full economies are caving in," said Winnie Kiiru, a senior technical advisor to the Elephant Protection initiative, an alliance formed by 20 African governments to combat the 2000s poaching crisis.

"So we need a paradigm shift in how we think about funding conservation and motivation for African people to preserve wildlife. Is it just so some guy can pay his money to come to Africa and take a photograph? I as a conservationist now think that what I need is to rally a kind of cultural sentiment, where a Kenyan wants to see wildlife because it is a part of us, part of our heritage, part of who we are."

Whatever the solution, it needs to be found soon.

"Of course people say we should diversify income streams. Well, yes. But that is not so easy to institute across the continent because the funding stream has been tourist for so long," said Mr Davenport.

"The trophy hunting side has been in decline for a while. So what is plan B for these large areas only supported by trophy hunting? That now needs to come much more quickly."