Shark Men stats show rapid migrations
2012-04-16 22:28
Johannesburg - The Shark Men project presents a unique opportunity for researchers, the department of environment said on Monday, dismissing fears that it could pose a danger to bathers.
Spokesperson Zolile Nqayi said the project would enable researchers to find out where sharks moved at different stages of their lives and how they moved between and used different habitats on shorter time-scales.
The Shark Men project is a collaborative research initiative on large sharks in South African waters.
United States-based documentary maker Chris Fischer has been in the country for the past month capturing and filming sharks in their natural habitat for the National Geographic documentary Shark Men.
Nqayi said initial data was already showing rapid large-scale and coastal migrations.
These included several white sharks moving into the Southern Ocean and one moving between the Eastern Cape and KwaZulu-Natal and back, showing where it stopped along the way.
"Genetic and other microbiological results will take longer to analyse, but should allow statistically valid conclusions to be made about white sharks' populations and their biology," he said.
He dismissed fears that the study would attract sharks to populated beaches, saying statements to this effect were misleading and inappropriate.
"These alarmist statements [by] individuals are creating unnecessary public concern," he said.
High shark alert
Dirk Schmidt, a wildlife photographer and author of White Sharks, has called for the immediate issuing of a high shark alert. "I believe it to be prudent, and as a preventative measure, that a high shark alert is issued and maintained, during, and for several days after, the filming activity.
"Unusual white shark behaviour and an increased presence and possible shark-human interaction or even attacks cannot be excluded."
Nqayi said the sampling protocols developed for the project were the most comprehensive for any similar marine work in South Africa, if not globally for sharks.
"They were at all times designed to have the minimum impact on the sharks needed to accomplish the scientific objectives."
They had been improved by assessing each shark immediately after capture as part of the project and before tagging or other work was done to ensure minimum impact.
"One of the aspects of the research also involves measuring the stress of sampling on sharks, which will guide future sampling."
He said the department had recently completed a draft conservation plan for sharks.
"The plan emphasises that sharks are both poorly understood and that many species are threatened by human activities," he said.
"It also notes the need for research in order to understand the basic life histories of a number of species, including migration, reproduction and population status."
Multi-user marine environment
He said the Shark Men initiative was a unique opportunity for researchers to answer these questions.
Nqayi said that when the research work shifted to False Bay, concerns for human safety would become the main public issue.
"This is understandable as False Bay is a multi-user marine environment, and also has had a number of shark attacks recently."
He said additional precautionary measures had been put in place by not allowing any chumming - use of bloody bait - within the Table Mountain National Park Marine Protected Area.
This incorporated the coast from Cape Point to Muizenberg to a distance of at least five kilometres offshore.
Nqayi said the potential for sharks to move away from cage diving areas following sustained increased activity had been taken into consideration.
The amount of time a research vessel could spend in an area was being restricted to 48 hours followed by a break of similar length before sampling could resume in that area.
- SAPA
