JOHANNESBURG, May 8 (Xinhuanet) -- Overgrowth of elephant population in South Africa's Kruger National Park (KNP) has posed threats to the safety of bio-diversity and human beings in the area, an expert has warned.

    The park is now struggling to cope with more than 11,500 elephants since there will be not enough vegetation to feed the jumbos, the park's former conservation head Willem Gertenbach said,suggesting the population should be controlled through regular culling.

    "The park's bio-diversity will suffer irreparable damage if the numbers are not slashed soon," he was quoted as saying by Saturday's newspaper The Citizen.

    At least four persons have been trampled to death by elephants and more than three were injured in South Africa in the past six months. The death of ecologist Kay Hiscocks on Tuesday near the KNP shocked the country.

    "The jumbos might have been attacking people because of behavioral changes brought about by their frustration and stress at the overcrowding," said Gertenbach, who retired at the end of 2002.

    He said environmental guidelines allowed no more than 8,000 elephants in the national park, and regular culling was carried out to control numbers before the country's environmental affairs ministry placed a moratorium on culling in 1994.

    Other options such as contraception and translocation have beentried but proved unsuccessful, and the elephant population has been growing at 7 percent annually since 1994, Gertenbach said, adding that the only way was to "reduce them by a properly implemented culling process."

    Even the International Fund for Animal Welfare (IFAW), one of the parties who were against culling, agreed in 1998 that culling was the most reliable option. But IFAW later sacked their representative for supporting the KNP's elephant management program.

    The program was likely tabled again in two or three months, butthe environmental affairs ministry will have the final say since the moratorium is still in place.

    But Anthony Hall-Martin, who worked for the KNP for 25 years and has authored books on elephants, argued that human activities should be more responsible for elephant-related casualties.

    "You would think that the more contact the elephants have with people, the more tolerant they become, but they are large wild animals and they have got to be treated with respect," Hall-Martintold the South African Press Association. "The basic caution is that an elephant is a big dangerous animal and don't get too close.People ignore this when they become too familiar with the animals and think it is safe."

    "An elephant is an individual with its own temperament and someare more or less likely to attack. You never know when an elephanthas an injury, toothache or is more aggressive that usual," he said. Enditem