A distrubing new trend involving the poaching of elephants has scientists greatly disturbed. A team of scientists who examined shipments of elephant tusks from Africa that were seized has determined that most of the ivory comes from elephants there were killed in just the last three years, which suggests that poaching is going strong in Africa and may even be strengthening.

The findings, which were published in the Porceedings of the National Academy of Sciences, indicates that poaching may be surging in the last decade, and it may be at least partially responsible for a tremendous decline in elephant populations.

A study last year examined 28 large seizures of ivory between 1996 and 2004 and matched it to 1,350 DNA ssamples in 29 diferent countires, allowing them to map the sources of the ivory and look at patterns of poaching. But some had suggested that these were just older shipment sof ivory. However, this new study indicates that’s not the case: they analyzed the carbon-14 in the pulp cavity of the ivory, using a sample from the base that would have only grown in the last two or three months before the elephant’s death to confirm that these are new ivory samples.

“Carbon-14 measurements on 231 elephant ivory specimens from 14 large ivory seizures (≥0.5 ton) made between 2002 and 2014 show that most ivory (ca. 90%) was derived from animals that had died less than 3 y before ivory was confiscated,” the abstract states. “This indicates that the assumption of recent elephant death for mortality estimates of African elephants is correct: Very little “old” ivory is included in large ivory shipments from Africa. We found only one specimen of the 231 analyzed to have a lag time longer than 6 y. Patterns of trade differ by regions: East African ivory, based on genetic assignments of geographic origin, has a much higher fraction of “rapid” transit than ivory originating in the Tridom region of Cameroon–Gabon–Congo. Carbon-14 is an important tool in understanding patterns of movement of illegal wildlife products.”