International rhino horn trade has already taken its toll on the poor animal. Well, hunting has also led to the decrease of its horns, if a study has to be believed.
The researchers from the University of Cambridge came up with the findings while measuring the horns of 80 rhinos, photographed in profile view between 1886 and 2018. The photographs, held by the Rhino Resource Centre – an online repository – included all five species of rhino: white, black, Indian, Javan and Sumatran. “Horn length was found to have decreased significantly in all species over the last century,” the researchers noted.
This is for the first time that horn length has been measured over a long timeframe, as the horns are so valuable that strict security protocols typically prevent researchers accessing them for study.
RHINO HORNNS; SMALLER DUE TO HUNTING
The researchers believe that rhino horns have become smaller over time due to intensive hunting. Moreover, the hunters target and shoot down rhinos with the longest horns. As such, the researchers feel that this left an increased number of smaller horned rhinos, which reproduced more and passed on their smaller traits to future generations.
“We were really excited that we could find evidence from photographs that rhino horns have become shorter over time. They’re probably one of the hardest things to work on in natural history because of the security concerns,” said Oscar Wilson, formerly a researcher in the University of Cambridge’s Department of Zoology, first author of the report. Wilson is now based at the University of Helsinki, Finland.
He added: “Rhinos evolved their horns for a reason – different species use them in different ways such as helping to grasp food or to defend against predators – so we think that having smaller horns will be detrimental to their survival.”
RHINO; HUMAN PERCFEPTION
In the study of thousands of drawings and photographs made over the last 500 years, they also found a dramatic shift in human perceptions of rhinos around 1950, when the animals became the focus of conservation efforts rather than hunting.
“We found that we can use images from the last few centuries to visualise how human attitudes towards wildlife have changed, and how artists have influenced these views,” said Dr Ed Turner at the University’s Department of Zoology, senior author of the report.
Many hundreds of photographs showing rhinos shot dead by hunters, taken in the late 19th and early 20th century, are included in the collection. These include a photograph of American President Theodore Roosevelt, taken in 1911, standing triumphantly over a black rhino he had just killed.
The images suggest that there was very little effort to promote rhino conservation to the public before the 1950s. However, after this the focus suddenly changed from hunting the animals to trying to keep them alive. The researchers say this shift coincides with the collapse of European empires, when African countries became independent and European hunters no longer had easy access to Africa for hunting.
More recent images appear to reflect a growing awareness of the threats facing the natural world.
“For at least a few decades now there’s been much more of a focus on the conservation of rhinos – and this is reflected in the more recent images, which relate to their conservation in sanctuaries or their plight in the wild,” said Wilson.
The Rhino Resource Centre holds over 5000 illustrations and photographs of rhinos, drawn together from extensive archival research and submissions from rhino experts. Artwork covers over 500 years, and photographs cover the past 150 years.
