Excavations of giant armadillos alter environmental conditions and provide new resources for a range of animals in their southernmost range

DI BLANCO, Y. E.; DESBIEZ, A. L. J.; DI FRANCESCANTONIO, D.; DI BITETTI, M. S.

JOURNAL OF ZOOLOGY (1987)

WILEY-BLACKWELL PUBLISHING, INC

Lugar: Londres; Año: 2020 vol. 311 p. 227 - 238

0952-8369

Burrowing species are considered important ecosystem engineers that increase landscape heterogeneity, create subterranean shelters, and provide foraging opportunities. We measured and described different aspects of giant armadillo (Priodontes maximus) excavations (size), and differences generated in relation to the surrounding environment (vegetation, humidity, temperature) in three sites of the Argentine Chaco Region. We used camera-traps in two protected areas to monitor the use of burrows by other species, and tested two alternative hypotheses: (1) in extreme physical environments, giant armadillo burrows provide thermal protection, or (2) new foraging opportunities for other species. Greater litter cover and depth were found in giant armadillo burrows, and more bare ground in spoil piles, collaborating with habitat heterogeneity. Burrows presented higher humidity and more moderate temperatures, with lower temperatures during hot months and higher temperatures during cold months. Out of 48 vertebrate species recorded by camera-traps, 27 taxa (19 mammals, 14 birds, and one reptile) were recorded using burrows. White-lipped peccaries (Tayassu peccari) and collared peccaries (Pecari tajacu) used these burrows more frequently than other mammals, and medium-sized carnivores tended to investigate burrows, probably searching for prey. In no instances animals other than giant armadillos stayed inside burrows to rest. Medium sized species interacted more frequently and smaller species used giant armadillo burrows to a lesser degree than larger ones, suggesting that these excavations may provide benefits which may not be provided by other smaller burrowing species of the region. The probability of use of burrows decreases with time, suggesting that burrows provide foraging opportunities. Further reduction in the distribution of the giant armadillo is therefore likely to have effects on habitat heterogeneity and biodiversity, probably impacting the fitness of species that use their burrows as foraging sources.