Nine‐banded armadillo (Dasypus novemcinctus) activity patterns are influenced by human activity

Abstract

As the human footprint upon the landscape expands, wildlife seeking to avoid human contact are losing the option of altering their spatial distribution and instead are shifting their daily activity patterns to be active at different times than humans. In this study, we used game cameras to evaluate how human development and activity were related to the daily activity patterns of the nine-banded armadillo (Dasypus novemcinctus) along an urban to rural gradient in Arkansas, USA during the winter of 2020-2021. We found that armadillos had substantial behavioral plasticity in regard to the timing of their activity patterns; >95% of armadillo activity was nocturnal at six of the study sites, whereas between 30% and 60% of activity occurred during the day at three other sites. The likelihood of diurnal armadillo activity was best explained by the distance to downtown Fayetteville (the nearest population center) and estimated ambient sound level (both indices of human activity) with armadillos being most active during the day at quiet sites far from Fayetteville. Furthermore, armadillo activity occurred later during the night period (minutes after sunset) at sites near downtown and with higher anthropogenic sound. Anecdotal evidence suggests that the observed activity shift may be in response to not only human activity but also the presence of domestic dogs. Our results provide further evidence that human activity has subtle nonlethal impacts on even common, widespread wildlife species. Because armadillos have low body temperatures and basal metabolism, being active during cold winter nights likely has measurable fitness costs. Nature reserves near human population centers may not serve as safe harbors for wildlife as we intend, and managers could benefit from considering these nonlethal responses in how they manage recreation and visitation in these natural areas.

Wildlife associates of nine‐banded armadillo (Dasypus novemcinctus) burrows in Arkansas

“…We used Timelapse 2.0 (Greenberg et al, 2019) to review all photographs and assign species ID to each wildlife trigger. We combined all photographs taken within a 5‐min period as a single detection to reduce the likelihood of double‐counting individuals (DeGregorio et al, 2021). For each wildlife detection, we identified the species present, the number of individuals visible, and we recorded which part of the burrow an animal interacted with including passing by (no interaction with burrow), apron (animal interacting with the mounded sand, bare ground, or leaf litter piled in front of the burrow), entrance (animals sniffing, foraging, or inspecting the opening to the burrow), or interior (animals that moved beyond the entrance of a burrow to enter, exit, or investigate the tunnel of the burrow).…”

Ensamble de mamíferos medianos y grandes del Parque Natural Provincial “Islas y Canales Verdes del Río Uruguay”, Entre Ríos, Argentina: diversidad, uso del espacio, patrones temporales, y desafíos para su conservación

“…Bos taurus presento un patrón de actividad diurna como es esperable en esta especie (Piccione, Giannetto, Casella, Caola, 2010). Dasypus novemcinctus en este estudio fue nocturna; esta especie puede variar sus patrones temporales en función de la presencia humana, mostrando en este caso uno principalmente nocturno (DeGregorio et al, 2021). Por este motivo sería interesante evaluar si D. novemcinctus cambia a un patrón más diurno al disminuir la presión de cacería.…”

Patrones de actividad de mamíferos alrededor de la línea transportadora de gas natural de Camisea en la Reserva Comunal Machiguenga, Cusco, Perú

“…), se evidenció que en la RCM presentaron un patrón de actividad nocturno, similar a lo reportado tanto para D. novemcinctus como D. pastasae en otros bosques amazónicos de la región neotropical (Norris et al 2010, Blake et al 2012, Aya-Cuero et al 2021. Aunque se sabe que algunos armadillos presentan una plasticidad considerable en su actividad alrededor del día (DeGregorio et al 2021), en regiones neotropicales, el patrón de actividad diaria parece estar relacionado inversamente con los picos de temperatura (Bernardes et al 2015). Dado que los armadillos son considerados homeotermos imperfectos (McNab 1985), se ha sugerido a la variación en la temperatura como factor clave en la regulación de su actividad diaria, incluso más que la luz disponible (Bernardes et al 2015).…”