Josephine Smit, who studies elephant behavior as a researcher with the Southern Tanzania Elephant Program, says that among the female elephants she tracks at Ruaha National Park, an area that was heavily poached in the s and s, 21 percent of females older than five are tuskless. As in Gorongosa, the numbers are highest among older females. About 35 percent of females older than 25 are tuskless, she says. And among elephants ages five to 25, 13 percent of females are tuskless.
Smit, a doctoral candidate at the University of Stirling, in Scotland, says the data have not yet been published, though she presented the findings at a scientific wildlife conference last December.
Poaching has also pushed tusk sizes down in some heavily hunted areas, such as southern Kenya. A study conducted by Duke University and the Kenya Wildlife Service compared the tusks of elephants captured there between and with those of elephants culled between and that is, before significant poaching took place in the late s and early s and found significant differences. Survivors of that period of intense poaching had much smaller tusks—they were about a fifth smaller in males and more than a third smaller in females.
The pattern repeated in their offspring. On average, male elephants born after had tusks 21 percent smaller than the males from the s, and 27 percent smaller than the females from that period. Despite the wave of human-influenced tusklessness in recent decades, elephants missing their tusks are surviving and appear healthy, according to Poole.
Scientists say that the significant proportion of elephants with this handicap may be altering how individuals and their broader communities behave, and they want to find out if, for example, these animals have larger home ranges than other elephants because they might need to cover more ground to find recoverable foods. Tusks are essentially overgrown teeth. The work elephants do with their tusks is vital for other animals too. Tusk action also helps create habitats.
Certain lizards, for example, prefer to make their homes in trees roughed up or knocked over by browsing elephants. If elephants are changing where they live, how quickly they move, or where they go, it could have larger implications for the ecosystems around them. Now, Long and a team of ecology and genetic researchers are starting to study how tuskless elephants are navigating their lives.
In June, the team started tracking six adult females in Gorongosa—half with tusks, half not—from three different breeding herds. Elephants are highly social and form tight family groups. Their goal is to uncover more information about how these animals move, eat, and what their genomes look like. Long hopes to detail how elephants without the benefit of tusks as tools may alter their behavior to get access to nutrients.
Another collaborator, Shane Campbell-Staton, an evolutionary biologist at the University of California Los Angeles, will study blood, searching for answers about how genetics influences the phenomenon of tusklessness.
Tusklessness does seem to occur disproportionately among females. African elephant tusks are curved forward and average around 5 to 8 feet 1. Male elephants grown significantly larger tusks than female elephants. African elephants have become an icon for Africa and are among the most intelligent animals in the world.
Being the largest land animal, elephant play an important part in balancing the natural ecosystem. However, due to their beautiful ivory tusks poaching continues to take place.
Therefore, more than ever we need to protect them magnificent animals. What are African elephant tusks? Are tusks found on both male and female African elephants? At what age do African elephants grow tusks? What do African elephants use their tusks for?
Can an elephant regrow their tusks? How big are African elephant tusks? It helps to be able to put the elephant you are trying to identify into a size category. Size categories correspond to rough age ranges.
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