A New Examination of Echolocation Calls of Some Neotropical Bats (Emballonuridae and Mormoopidae)

In northwestern Belize, two emballonurids Rhynchonycteris naso and Saccopteryx bilineata) and three mormoopids Pteronotus parnellii, P. davyi, and P. personatus) were examined acoustically with the Anabat II bat detector and associated analysis system. R. naso used calls consisting of a short constant frequency CF) at 47 kHz and concave downward frequency modulated FM) sweep to about 40 kHz with two strong harmonics. Echolocation sequences of S. bilineata revealed a paired cadence of calls. Both signals in a pair slowly increased in frequency, forming a quasi-CF QCF) component and terminated with a short, downward FM sweep. The initial call of a pair ranged from 44.5 to 46.6 kHz and the second ranged from 46.6 to 48.7 kHz. P. parnellii used a long CF call at 63.5 kHz, with a terminal downward FM sweep to about 54.5 kHz. P. davyi produced calls with an initial short CF at 68.1 kHz, a downward FM sweep, and a terminal short CF at 58.0 kHz. P. personatus emitted calls similar in shape to P. davyi, with the initial CF at 83.0 kHz and the terminal CF at about 68.0 kHz. Previous descriptions of echolocation calls for these species compare favorably with those obtained in this study, but the Anabat equipment generally revealed more variation and detail than previously described. The echolocation calls described in this study provide precise vocal signatures for the accurate identification of free-flying individuals of the species studied.