This represents a huge setback for the conservation movement, following a year in which only 20 rhinos were poached for their ivory tusks.
Of the 50 rhinos killed in 2015, 42 were critically endangered black rhinos, according to the Lowveld Rhino Trust.The group said it could only verify 50 illegal kills, and that the loss was probably greater.
Most of the poaching occurred in a region that contained the only populations of white and black rhinos considered to be genetically and demographically viable.
The news is especially troubling because it comes after a five-year period in which poaching had been largely brought under control, allowing for a small spike in rhino numbers.
The Lowveld Trust, however, did make note of some positive news in 2015.
It included the arrests of several poachers working for powerful syndicates, including the conviction of a longtime suspected poacher who was sentenced to 20-35 years in prison, after admitting to killing four rhinos.
Lowveld is hopeful that with increased community support, 2016 will be a year marked with more success than failure.
However, this is and will remain at a crisis stage in all African states that boast rhino populations.
According to Save the Rhino, there are about 20,000 white rhinos and 5,000 black rhinos in Africa.
At the beginning of the 20th century, there were about 500,000 rhinos across Africa and Asia.
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