Rhinoceroses also are heavily poached for their horns, which some Asian cultures believe contain medicinal properties.
TRAFFIC, a global wildlife trade monitoring network, says there are between 47,000 and 93,000 elephants in Zimbabwe. The gap is due to the fact that full-fledged surveys of the animals have not been carried out since 2007, said Richard Thomas, the organization's spokesman.
Across Africa, there are close to 500,000 elephants, a fraction of the nearly 10 million that roamed there just 100 years ago.
The U.S. Fish and Wildlife Service this month signaled its worries about the future of Zimbabwe's herds in a decision blocking the importation of African elephant trophies taken in Zimbabwe during 2014. Noting the cyanide poisoning of 300 elephants last year in Zimbabwe's Hwange National Park, the agency said it has "significant concerns about the long-term survival of elephants in Zimbabwe."
The ban also applies to Tanzania.
The Obama administration in February published a national strategy for combating the multibillion-dollar poaching industry, relying on many of the same tactics used against terrorist organizations and drug cartels. The plan outlines a "whole of government approach" that includes working with other countries to increase the number of investigations and arrests, using high-tech gear to identify poaching hot spots, and targeting the bank accounts of wildlife traffickers and the corrupt bureaucrats who assist them.
"Our findings shine a bright light on Zimbabwe, Mozambique, Tanzania, Sudan, and Kenya, where poachers move across borders with near impunity, slaughter elephants with complete disregard, and use the ivory to fund violent operations across the continent," said Born Free USA's Roberts. "Global leaders cannot stand by while the human tragedy and poaching crisis continue.
Zimbabwe, the report said, could become a poaching hot spot with little warning.
Mugabe has led the country since independence from British rule in 1980. In his early years in power, he expanded public education and health services, making Zimbabwe a beacon on the continent. But Zimbabwe's economy went into meltdown in 2000 after Mugabe ordered the seizure of thousands of white-owned commercial farms, leading to the collapse of the agriculturally based economy, once the region's breadbasket.