EPOW - Ecology Picture of the Week

Mongolian Gerbil

Mongolian Gerbil (Meriones unguiculatus), Family Muridae
Yol Valley, Mongolia

Explanation:  Deep in the heart of the Gobi Desert of the central Asian steppe country resides this tiny, nervous rodent.  This is a wild Mongolian gerbil.  

We are in the arid Gobi Desert of southern Mongolia.  Here, gerbils share their rocky steppe habitats with other iconic small mammals, particularly pikas.  In fact, I saw a Daurian pika in the same spot as the gerbil, just a few minutes previous.  And I have to wonder if such close associations between species confers some sort of advantage -- perhaps taking advantage of each other's predator awareness and alarm calls?  Or if it confers a disadvantage, such as spread of parasites or disease?  This seems to be totally unstudied and unknown. 

  
However, one study (Wang and Zhong 2006) discovered that Mongolian gerbils and Daurian pikas respond differently to rainfall and subsequent green-up of vegetation that both consume as a main food source.  In the broad steppe biome, the gerbils tend to inhabit short grasslands and the pikas prefer taller vegetation, although clearly there is some overlap in their local distributions.

Mongolian gerbils breed mainly from February to September, with peak breeding in March to August.  However, population growth rates apparently are not related to population density, but rather to low temperature and low precipitation which keep grasslands short and open.  

Mongolian gerbils are found from northeast China, through Mongolia, and into Russia.  They tend to be active during the day but hide in burrows when the weather becomes too hot or inclement.  They are colonial, although the ones I saw were all solitary, feeding on the sparsely-distributed forbs and seeds.  

    
Information:
    Liu , W., X. Wan, and W. Zhong. 2007. Population dynamics of the Mongolian gerbils: Seasonal patterns and interactions among density, reproduction and climate. Journal of Arid Environments 68(3):383-397.
    Wang, G., and W. Zhong. 2006. Mongolian gerbils and Daurian pikas responded differently to changes in precipitation in the Inner Mongolian grasslands. Journal of Arid Environments 66(4):648-656.