Actual cheetah numbers may be lower than currently estimated

London, May 4 (IANS) Amid fears that the fastest land mammal is racing to extinction, researchers including one Indian, have suggested that the current estimates of the number of cheetahs in the wild are at best a "guesswork".

In the study, the researchers found that the population in the cheetah stronghold of Maasai Mara, Kenya, is lower than previously thought.

In the early 1900s it was believed that around 100,000 cheetahs roamed the Earth.

The most recent estimate by the International Union for Conservation of Nature (IUCN) puts the figure at 6,600 -- mainly in eastern and southern Africa.

However, a team of scientists says this number is simply a best guess, given the difficulty of counting cheetahs accurately.

The researchers have now developed a new method to accurately count cheetahs, which in time will help determine the magnitude of the threats they face and assess potential conservation interventions.

These measures provide crucial insights about big cat ecology that aids their conservation. For example, India has been considering the reintroduction of the African cheetah. Even in a prey-rich area like the Maasai Mara, the density of cheetahs is low, suggesting that the resource requirements for these cats are perhaps much larger than would be available currently in the Indian subcontinent,” explained study co-author Arjun Gopalaswamy from the Indian Statistical Institute in Bengaluru.

The study was published in the journal PLOS ONE.

The truth is that estimates of cheetah numbers are only best guesses, because cheetahs are a lot harder to count accurately than one might think. They naturally occur at low densities and move large distances, making them difficult to find,” said lead author Femke Broekhuis from the University of Oxford.

During a three-month period, researchers in five vehicles extensively covered the Maasai Mara National Reserve and surrounding wildlife conservancies in search of cheetahs.

The field team photographed each cheetah that was seen and identified each individual based on its unique coat pattern.

These data were then analysed using an advanced Bayesian Spatially Explicit Capture Recapture (SECR) statistical model.

This technique, incorporating information such as identity and location, is more powerful than previous methods used to estimate cheetah numbers.

The study revealed an average of 1.28 adult cheetahs per 100 square km in the Maasai Mara.

• much lower than previously thought - around half, in fact.

  The 'spatially explicit' method used can distinguish 'visiting' animals from those that reside permanently within the surveyed area, avoiding potential overestimation, the researchers said.