The development of black-tailed prairie dog (Cynomys ludovicianus) burrow mounds was monitored for three years. Entrances were flagged at points where a prairie dog was observed digging into the ground (primary entrances, n = 22) and digging out of the ground (secondary entrances, n = 8). In all samples it was observed that primary entrances became dome mounds and secondary entrances crater mounds. It is suggested that, although induced airflow (presently, a popular model) may partly explain the presence of mounds, architectural types (dome vs. crater mounds) are the result of energy constraints associated with building materials that differ at the entrances.
Cincotta, Richard P.
"Note on mound architecture of the black-tailed praire dog,"
Great Basin Naturalist: Vol. 49
, Article 19.
Available at: http://scholarsarchive.byu.edu/gbn/vol49/iss4/19