Pretoria - Even though tourism is important in boosting the South African economy, scientists from the University of Pretoria (UP) have found that the presence of overzealous tourists could cause stress to penguin chicks leaving them susceptible to disease.
The study titled: "Urofaecal glucocorticoid metabolite concentrations in African penguin chick populations experiencing different levels of human disturbance," was led by a team of scientists at the university and had revealed that the close interaction of tourists with African penguin chicks could cause stress among the bird species.
The scientists warned that they found that the stress to the species could result in immunosuppression leaving them susceptible to disease, while at the same time resulting in their reproductivity also being reduced.
The African penguin is regarded as an endangered species found in South Africa and Namibia, with them being a popular attraction in the Western Cape.
The study published in the Conservation Physiology journal recently was taken up by DrJuan Scheun, a research fellow at the Mammal Research Institute at the university, alongside Professor Andre Ganswindt, director of the institute; and scientists from Exeter University in the United Kingdom, the University of the Western Cape and the Nelson Mandela University.
Scheun said the team conducted a study of the stress-related hormone levels of chicks at three sites within two breeding colonies on Robben Island and in Stony Point, both of which had varying levels of exposure to tourism.
The colony at Stony Point located next to a residential area in Betty's Bay was first colonised by the African penguin in 1982 and became the largest breeding colony in South Africa.
The second colony on Robben Island was recognised in 1983 following a 180-year absence of the species at the study site.
Scheun said a total of 320 000 tourists traveled to the island annually to visit several historical landmarks.
“Faecal samples from penguin chicks were collected to analyse stress-related hormone levels to understand the adrenocortical functions of penguins, especially when their environment appeared to be threatened by humans and their activities.”
He said they found that factors such as food shortages contributed to the elevated stress levels, however, it was the unpredictable human presence that was also likely responsible for the increase in stress-related hormone levels in chicks.
"The presence of overzealous tourists at the penguin breeding colonies, in particular, could be causing stress among the chicks. Tourist groups sometimes get too close to the penguins and feed them; they also get close to take photographs,” Scheun and Professor Ganswindt said.
"African penguin chicks are unable to avoid the strain brought on by the presence of humans as the chicks can’t swim yet unlike their parents, nor can they move with speed across the terrestrial landscape to escape a stressor so in a sense they have to ride it out,” he said.
In order to protect the well-being of the chicks, the scientists called for a limitation on the number of tourists who visited the penguin colonies.
This they said could be done through the management of tourism sites which should attempt to minimise all forms of activity around the important breeding colonies that were not already exposed to regular tourism.
"There should be legislation in place to help with this as if you have a fragile African penguin population you might want to consider restricting the number of visitors for the benefit of these birds.
While the scientists said they were aware that tourism was important for wildlife conservation it was for this reason that they suggested that access to colonies at the very least is guided, so as to ensure visitors were not taken too close to the penguins.