Extrinsic factors that affect the timing of armadillo activity

ZORRILLA, S.*; WINDEL, N.; Univ. of the Ozarks; Univ. of the Ozarks: Extrinsic factors that affect the timing of armadillo activity

The timing of above ground activity and the extrinsic factors that may influence this activity in nine-banded armadillos (Dasypus novemcinctus) were studied in two Arkansas populations during June and July 2001 and June 2002. We counted armadillos along transects and measured weather variables near the spot and time that each armadillo was seen. We also correlated sightings with lunar data and time since sunset. Armadillo activity was distinctly nocturnal. Statistically the same number of armadillos was observed after 0000 hr. as before. Barometric pressure was the only weather variable that correlated significantly with activity at night, but it accounted for little variation in the data. The fraction of moon illuminated with time since sunset provided a statistically significant multiple regression, but explained little variation in numbers of armadillos observed at night. Our summer observations of Arkansas armadillo populations distinctly differ from summer observations reported by others for a Florida population. The most likely explanations for the differences include differences in population densities, differences in annual weather patterns associated with differences in latitude and differences in weather data sampling methods.

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