Phrynocephalus vlangalii at Zoigê,Sichuan:Burrow Density and Depth and Their Implications

We measured the density of the burrows of Phrynocephalus vlangalii at the Zoigê Wetland at elevation about，NW Sichuan,by the quadrate method,and the depth by digging and using a blanch of alpine willows in September 2002.The density of P.vlangalii burrows declined with the plant coverage (r=-0.81,P<0.01),P.vlangalii shows preference to the desert with low plant coverage and could be used as one of indicator species for desertification of grassland.The depth of dwelling burrows was ≥74 cm,which is beyond the layer of frozen earth,living in these burrows is a behavioral mechanism of P.vlangalii to protect themselves from extreme low temperature,and the burrows with depth <74 cm may be used only for avoiding predation during foraging.