Digger Wasp
Sphex sp.
Image taken in the foothills of Four Peaks, Maricopa Co., Arizona. October 2008.
Sphecidae -- Thread-waisted Wasp Family
Naturalist hikers are wise to watch their feet when stepping so as not to take a tumble over a loose rock (hard to do when so much along the trail is vying for attention). In consequence the digging antics of wasps may come to notice because they are attracted to the bare soil of foot paths to excavate their nest-tunnels. If approached closely the digger wasp will cease digging and fly some distance away so as not to draw attention to her brood chamber within the tunnel.
There are many species of digger wasps found in the Sonoran Desert, and World-wide, the one pictured here may be Sphex lucae. The nest tunnels will be used to build brood chambers for their larval young. The wasps hunt crickets or other insects which are paralyzed with a sting (these wasps are not aggressive and rarely use their sting against people). The larvae of the wasps eat the insect prey alive and keep them alive by destroying the vital organs last!