Passive sound localization of prey by the pallid bat (Antrozous p. pallidus)

SummaryThe pallid bat (Antrozous p. pallidus) uses passive sound localization to capture terrestrial prey. This study of captive pallid bats examined the roles of echolocation and passive sound localization in prey capture, and focused on their spectral requirements for accurate passive sound localization.Crickets were used as prey throughout these studies. All tests were conducted in dim, red light in an effort to preclude the use of vision. Hunting performance did not differ significantly in red light and total darkness, nor did it differ when visual contrast between the terrestrial prey and the substrate was varied, demonstrating that the bats did not use vision to locate prey.Our bats apparently used echolocation for general orientation, but not to locate prey. They did not increase their pulse emission rate prior to prey capture, suggesting that they were not actively scanning prey. Instead, they required prey-generated sounds for localization. The bats attended to the sound of walking crickets for localization, and also attacked small, inanimate objects dragged across the floor. Stationary and/or anesthetized crickets were ignored, as were crickets walking on substrates that greatly attenuated walking sounds. Cricket communication sounds were not used in prey localization; the bats never captured stationary, calling crickets.The accuracy of their passive sound localization was tested with an open-loop passive sound localization task that required them to land upon an anesthetized cricket tossed on the floor. The impact of a cricket produced a single 10–20 ms duration sound, yet with this information, the bats were able to land within 7.6 cm of the cricket from a maximum distance of 4.9 m. This performance suggests a sound localization accuracy of approximately ±1° in the horizontal and vertical dimensions of auditory space. The lower frequency limit for accurate sound localization was between 3–8 kHz. A physiological survey of frequency representation in the pallid bat inferior colliculus suggests that this lower frequency limit is around 5 kHz.

[1]  G. Blasdel,et al.  Sound localization by the barn owl (Tyto alba) measured with the search coil technique , 1979, Journal of comparative physiology.

[2]  D. Griffin,et al.  Listening in the Dark , 1959 .

[3]  M. Ryan,et al.  Bat Predation and the Evolution of Frog Vocalizations in the Neotropics , 1981, Science.

[4]  G. Bell.  Behavioral and ecological aspects of gleaning by a desert insectivorous bat Antrozous pallidus (Chiroptera: Vespertilionidae) , 1982, Behavioral Ecology and Sociobiology.

[5]  L. J. Goldman,et al.  Prey recognition and selection by the constant frequency bat, Pteronotus p. parnellii , 1977, Behavioral Ecology and Sociobiology.

[6]  M. Ryan,et al.  Ear morphology of the frog‐eating bat (Trachops cirrhosus, family: Phyllostomidae): Apparent specializations for low‐freqency hearing , 1989, Journal of morphology.

[7]  Phenology of sound-producing arctiid moths and the activity of insectivorous bats , 1977, Nature.

[8]  The use of acoustical cues for prey detection by the Indian False Vampire Bat,Megaderma lyra , 1987, Journal of Comparative Physiology A.

[9]  R. Zollinger,et al.  Metastatic melanoma of the stomach. , 1960, American journal of surgery.

[10]  T. Vaughan.  Nocturnal Behavior of the African False Vampire Bat (Cardioderma cor) , 1976 .

[11]  Roger W. Barbour,et al.  Bats of America , 1979 .

[12]  M. Ryan,et al.  The ability of the frog-eating bat to discriminate among novel and potentially poisonous frog species using acoustic cues , 1983, Animal Behaviour.

[13]  Paul A. Racey,et al.  Feeding behaviour of captive brown long-eared bats, Plecotus auritus , 1991, Animal Behaviour.

[14]  J. Fiedler.  Prey catching with and without echolocation in the Indian false vampire (Megaderma lyra) , 1979, Behavioral Ecology and Sociobiology.

[15]  J. Fullard,et al.  The response of tympanate moths to the echolocation calls of a substrate gleaning bat, Myotis evotis , 1990, Journal of Comparative Physiology A.

[16]  T. O'Shea,et al.  Nocturnal and Seasonal Activities of the Pallid Bat, Antrozous Pallidus , 1977 .

[17]  R. Rübsamen,et al.  Comparative collicular tonotopy in two bat species adapted to movement detection,Hipposideros speoris andMegaderma lyra , 1988, Journal of Comparative Physiology A.

[18]  A. Moiseff,et al.  Sensitivity to ultrasound in an identified auditory interneuron in the cricket: a possible neural link to phonotactic behavior , 1983, Journal of comparative physiology.

[19]  R. Masterton.  Adaptation for sound localization in the ear and brainstem of mammals. , 1974, Federation proceedings.

[20]  M. Ryan,et al.  Acoustical resource partitioning by two species of phyllostomid bats (Trachops cirrhosus and Tonatia sylvicola) , 1985, Animal Behaviour.

[21]  A. Grinnell,et al.  The development of hearing in the pallid bat, antrozous pallidus , 1978, Journal of comparative physiology.

[22]  G. K. Morris,et al.  Bat Predation and Its Influence on Calling Behavior in Neotropical Katydids , 1987, Science.

[23]  Hans-Ulrich Schnitzler,et al.  Performance of Airborne Animal Sonar Systems: I. Microchiroptera , 1980 .

[24]  M. Ryan,et al.  The role of prey-generated sounds, vision, and echolocation in prey localization by the African batCardioderma cor (Megadermatidae) , 2004, Journal of Comparative Physiology A.

[25]  W. B. Davis,et al.  The Mammals of Texas , 1960 .

[26]  G. Neuweiler.  Foraging, echolocation and audition in bats , 1984, Naturwissenschaften.

[27]  R. T. Orr.  Natural history of the pallid bat, Antrozous pallidus , 1954 .

[28]  A. Guppy,et al.  Acoustical and neural aspects of hearing in the Australian gleaning bats,Macroderma gigas andNyctophilus gouldi , 1988, Journal of Comparative Physiology A.

[29]  M. Brock Fenton,et al.  Visual acuity, sensitivity and binocularity in a gleaning insectivorous bat, Macrotus californicus (Chiroptera: Phyllostomidae) , 1986, Animal Behaviour.

[30]  M. Brock Fenton,et al.  The foraging behaviour and ecology of animal-eating bats , 1990 .

[31]  James A. Simmons,et al.  Directional Hearing and Sound Localization in Echolocating Animals , 1987 .