Washington, Oct 30 : The social hierarchy among elephants dictates their movement when food resources are scarce, a new study by scientists from the US, Kenya and the UK, has revealed.

The researchers found that elephants led by older, more dominant matriarchs tromped significantly fewer miles to seek food than those a few rungs lower on the social ladder.

During the dry season, when water and vegetation were harder to come by, dominant groups travelled an average of 4-5 kilometres per day, about half the distance of subordinate groups that would trek 8-11 kilometres per day, the findings revealed.

Additionally, the researchers found that dominant groups in the study were more likely to stick to the preferred central, protected areas of the park, where fewer humans and more water were to be found.

“This work shows, for the first time, the role social factors play in the dispersal of elephants in an ecosystem .The findings have significant policy implications for how elephant populations are managed,” said lead author George Wittemyer, post-doctoral researcher from the University of California at Berkeley.

“Elephants can feed on a wide range of vegetation, but if they can't move, they're more likely to focus on a particular species - such as a favourite tree - potentially removing it from a local area.

“Being 'ecosystem engineers,' they are capable of changing wooded plains to complete grasslands. Elephants have huge space and resource needs, and are particularly impacted by land use changes. Fencing in these populations means blocking them from their normal behaviour of dispersal and migration, and changing the dynamics of how they interact with their environment,” Wittemyer added.

The research appears in the October issue of the journal Behavioral Ecology and Sociobiology. The elephants in this study occupied an open park. (ANI)