Journal of Comparative Physiology A

, Volume 199, Issue 8, pp 723–733

Severe constraints for sound communication in a frog from the South American temperate forest

  • Mario Penna
  • Alicia Plaza
  • Felipe N. Moreno-Gómez
Original Paper

DOI: 10.1007/s00359-013-0831-9

Cite this article as:
Penna, M., Plaza, A. & Moreno-Gómez, F.N. J Comp Physiol A (2013) 199: 723. doi:10.1007/s00359-013-0831-9

Abstract

The efficiency of acoustic communication depends on the power generated by the sound source, the quality of the environment across which signals propagate, the environmental noise and the sensitivity of the intended receivers. Eupsophus calcaratus, an anuran from the temperate austral forest, communicates by means of an advertisement call of weak intensity in a sound-attenuating environment. To estimate the range over which these frogs communicate effectively, we conducted measurements of sound level and degradation patterns of propagating advertisement calls in the field, and measurements of auditory thresholds to pure tones and to natural calls in laboratory conditions. The results show that E. calcaratus produces weak advertisement calls of about 72 dB sound pressure level (SPL) at 0.25 m from the caller. The signals are affected by attenuation and degradation patterns as they propagate in their native environment, reaching average values of 61 and 51 dB SPL at 1 and 2 m from the sound source, respectively. Midbrain multi-unit recordings show a relatively low auditory sensitivity, with thresholds of about 58 dB SPL for conspecific calls, which are likely to restrict communication to distances shorter than 2 m, a remarkably short range as compared to other anurans.

Keywords

Advertisement callsAuditory thresholdsFrogsSound propagationTorus semicircularis

Abbreviations

SPL

Sound pressure level

RMS

Root mean square

BTL

Best threshold of the low-frequency region

BTH

Best threshold of the high-frequency region

CFH

Center frequency of the high-frequency region

Copyright information

© Springer-Verlag Berlin Heidelberg 2013

Authors and Affiliations

  • Mario Penna
    • 1
  • Alicia Plaza
    • 1
  • Felipe N. Moreno-Gómez
    • 2
  1. 1.Programa de Fisiología y Biofísica, Instituto de Ciencias Biomédicas, Facultad de MedicinaUniversidad de ChileSantiagoChile
  2. 2.Instituto de Ciencias Ambientales y Evolutivas, Facultad de CienciasUniversidad Austral de ChileValdiviaChile