Serial killers of the sea
Great white sharks hunt down their prey in the same way as serial killers, scientists have found. Researchers used methods copied from criminology to show that great whites pick their targets in a highly focused fashion.
Prolific killers such as Peter Sutcliffe, the “Yorkshire Ripper”, behave in much the same way.
The scientists adapted geographic profiling, a mathematical technique used to track down serial criminals, to investigate the hunting habits of great whites.
They observed the location of 340 shark attacks and used the data to locate the sharks’ “anchor points”.
In criminal investigations, a series of linked crimes – usually murder, rape or arson – is used to determine the rough location of the perpetrator’s “anchor point”. Most often this is a home or place of work.
Serial killers or rapists tend to operate within a confined area around the anchor point, so knowing its location allows police to avoid being swamped with suspects and prioritise those who live or work in certain areas.
The shark scientists linked the “crimes” of great whites off the South African coast – attacks on seals – and found that the sharks had a well defined search base.
Their “anchor point” tended to be 100 metres seaward of where the seals accessed and left the island where they lived.
Smaller, younger, sharks exhibited more dispersed search patterns and were less successful hunters.
The research, led by Dr Neil Hammerschlag, from the University of Miami in the US, is reported in the Journal of Zoology, published by the Zoological Society of London.
Dr Steven Le Comber, an expert on geographic profiling at the School of Biological and Chemical Sciences at Queen Mary, University of London, said: “Geographic profiling is an interesting new way to study patterns of animal foraging, and especially predation.
“Shark hunting patterns are extremely difficult to study and the work here will have important implications for our understanding of the ways in which predators hunt their prey.”
Geographic profiling was developed by former Canadian “beat” policeman Kim Rossmo, now Professor of Criminal Justice at Texas State University.
It is extremely useful for whittling down lists of suspects and now routinely used by law enforcement agencies around the world.
In the Yorkshire Ripper case in the 1970s and 1980s police amassed a total of 268,000 potential suspect names and 4.5 million vehicle registration numbers.