NEOICHNOLOGY OF BURROWING OWLS: PALEOECOLOGICAL AND PLAEOHYDROLOGICAL IMPLICATIONS

Burrowing owls (Athene cunicularia) produce burrows for nesting and shelter, sometimes relying on underground structures created by other animals or even anthropogenic excavations. The species inhabits arid, semi-arid, and some coastal and insular regions of the Americas, and have protected status in some countries. In addition to typical siliciclastic substrate, they inhabit evaporite (e.g., White Sands desert, New Mexico) and carbonate (Florida, the Bahamas) settings. As they prefer well-drained areas, but rely on subterranean structures for thermoregulation and to avoid water loss, with typical burrow length of 2-3 m and depth of ~1 m, the gently inclined tunnels and nest chambers serve as bioindicators of surface erosion and minimum water table depth. This study examined the relationship between the owl burrows and fluctuations of the vadose zone. Using examples of georadar images from the White Sands desert (Entradichnus ichnofacies) and published data about co-located burrow and hydrological databases, it is possible to establish these zoogenic structures as constraints on regional aquifer patterns. Preliminary research suggests that A. cunicularia nests may be located <1-2 m above the long-term water table, with implications for reconstructing paleo-landscape and paleoecological conditions using fossil structures.