Researcher Sadie Ryan was about 50 meters away from the crowd of wild chimps, who screeched and scampered through the dense African forest.

‘We didn’t even know they were there, and suddenly they just started shouting,’ said Ryan, an assistant professor of ecology at the State University of New York College of Environmental Science and Forestry.

Such experiences contributed to Ryan’s enduring interest in primates. Her passion led her to become the lead author of a scientific article revealing how contagious diseases became a major threat to the survival of African great apes.

‘I’ve been keen on primates and infectious disease ecology for a long time,’ Ryan said. ‘The infectious disease realm is just part of a bigger story of conservation biology.’

Since 2008, Ryan worked with researchers at the University of California-Santa Barbara as well as an ecologist at the University of Cambridge to compile information for the article titled, ‘Consequences of Non-Intervention for Infectious Disease in African Great Apes,’ currently published in the online journal PLos ONE.

The increasing death rates of African great apes, from human sicknesses, are as threatening to African gorillas and chimpanzees as poaching and wildlife destruction, according to the article. Human illnesses as mild as the cold or flu could have a large effect on apes, Ryan said.

Such illnesses can be a result of increasing human tourism.

‘The problem is the more tourism you have, the more likely you are to get some of these disease spill-over events, where someone with the flu will get too close and cough near a gorilla,’ Ryan said.

Will Helenbrook, a graduate student at ESF studying conservation biology, is also interested in how people are playing a role in increasing the risk of great apes contracting human diseases.

Helenbrook said he uses primate and parasite DNA samples from scat in lab tests to determine how humans are affecting primate populations through environmental destruction, increases in human populations near wildlife preserves, and the meat and pet trades,

These factors could cause less variation in ape populations, or more instances of inbreeding, Helenbrook said.

‘One disease could devastate an entire population,’ he said.

The team also found that more dangerous sicknesses for humans, such as the potentially fatal Ebola virus, would harm a great ape population for more than 130 years. In fact, the population may never recover from such an outbreak, Ryan said.

Ryan said the data needed to conduct these demonstrations is difficult to find.

‘Finding sick animals in the wild is very hard. It takes a lot of intensive field work to know these animals so well,’ she said.

Limiting tourism is an arguable way to protect chimps and gorillas from increasingly deadly human diseases, Ryan said. But, she said, it could be very difficult to keep tourists who paid thousands of dollars to see African chimps or gorillas away.

Decreasing tourism is an arguable solution that may be impractical, as it could also reduce the money going toward conservation efforts and increase poaching, among other risks, according to the article.

Another controversial solution for the protection of the apes is vaccination, which has worked in the past for illnesses that already have effective human vaccinations, such as measles, Ryan said. But for more complicated respiratory sicknesses, taking this interfering step to African apes would be expensive and could have unknown results, she said.

‘We don’t even really have these vaccinations right for humans yet,’ she said.

Organizations focusing on strengthening populations by preventing hunting and protecting habitats are solutions that Helenbrook said he thinks would be successful by decreasing inbreeding and apes’ stress levels.

Ryan is contacting major conservation NGOs, including the Wildlife Conservation Society, among others. Another noninterventionist way to protect the African great apes is to initiate health programs for communities surrounding the apes’ habitats. These programs would include hygiene education and installing better water filters in communities, Ryan said.

Said Ryan: ‘We want to put this information out there and show, in very simple terms, that very big impacts happen, and we need to be aware of them.’

smhazlit@syr.edu

 

Published on February 12, 2012 at 12:00 pm

Contact Shannon: smhazlit@syr.edu