Wing morphology and flight performance in Rousettus leschenaulti

Abstract

We studied development of wings of Leschenault's rousette, Rousettus leschenaulti. Wingspan and wing area grows linearly until 45 days of age. Young bats begin to flutter at 45 days, manage sustained flight at 60 days, and achieve independent foraging flight at 75 days. Aspect ratio varies until 15 days, and adult proportions are attained at 2 months. Wing loading decreases linearly until 50 days and thereafter increases slowly, possibly because of completion of growth of wing area. Wingspan growth fits a logistic model, whereas wing area growth fits a Gompertz model. Minimum predicted flight power (P_mp) and maximum range power (P_mr) begin to increase linearly after remaining relatively constant for 30 days. At 150 days both are nearly equal to 65% of the power requirements of postpartum females. The predicted minimum power speed (V_mp), maximum range speed (V_mr), and minimum theoretical radius of a banked turn (rmin) decrease for 40 days, thereafter increase linearly, and at 150 days all are close to 90% of the respective values of the postpartum females.