Interindividual use of echolocation calls: Eavesdropping by bats

SummaryThe use of other individual's echolocation calls by little brown bats, Myotis lucifugus, was tested by observing the response of free-flying bats to presentations of recorded echolocation calls and artificial sounds. Bats responded by approaching conspecific calls while searching for food, night roosts, nursery colonies and mating/hibernation sites. Response was low or non-existant to other sounds. While searching for prey, M. lucifugus also responded to the echolocation calls of Eptesicus fuscus, a sympatric species with overlapping diet but distinctly different echolocation calls. Subadults were especially responsive to conspecific calls.All four situations in which the bats responded involve patchily distributed resources at which bats accumulate. Concentrations of echolocation calls thus likely serve as cues regarding the location of resources. Individuals approaching feeding groups, for example, could increase prey detection range by up to 50 times over individuals relying solely on their own echolocation.Although the costs associated with eavesdropping may be negligible for M. lucifugus, for other species, particularly territorial ones, being conspicuous may be a disadvantage and the possibility of being over-heard by other bats may have been one factor involved in the evolution of echolocation call design.

[1]  James A. Simmons,et al.  Apparatus for research on animal ultrasonic signals , 1979 .

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

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

[4]  L. Miller.  Physiological responses of green lacewings (Chrysopa, Neuroptera) to ultrasound , 1971 .

[5]  M. Brock Fenton,et al.  Adaptiveness and Ecology of Echolocation in Terrestrial (Aerial) Systems , 1980 .

[6]  GILLIAN D. SALES.  Acoustic orientation , 1974, Nature.

[7]  Terry A. Vaughan,et al.  Opportunistic Feeding by Two Species of Myotis , 1980 .

[8]  M. Fenton,et al.  Variation in the diet of Myotis lucifugus (Chiroptera: Vespertilionidae) , 1976 .

[9]  Charles R. Michael,et al.  The echolocation of flying insects by bats , 1960 .

[10]  M. Fenton,et al.  Opportunistic feeding by desert bats (Myotis spp.) , 1976 .

[11]  T. Kunz,et al.  Feeding Strategies of the Little Brown Bat, Myotis Lucifugus, in Southern New Hampshire , 1977 .

[12]  R. Busnel,et al.  Animal Sonar Systems , 1980, NATO Advanced Study Institutes Series.

[13]  W. E. Evans,et al.  Adaptiveness and Ecology of Echolocation in Toothed Whales , 1980 .

[14]  M. Brock Fenton,et al.  Social behavior of the little brown bat, Myotis lucifugus , 1979, Behavioral Ecology and Sociobiology.

[15]  M. Fenton,et al.  Echolocation and feeding behaviour in four species of Myotis (Chiroptera) , 1979 .

[16]  M. Fenton.  Summer activity of Myotis lucifugus (Chiroptera:Vespertilionidae) at hibernacula in Ontario and Quebec , 1969 .

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

[18]  M. Fenton,et al.  The influence of moth hearing on bat echolocation strategies , 1979, Journal of comparative physiology.

[19]  R. L. Peterson,et al.  Notes on Vampyrum spectrum, the false vampire bat, in Panama , 1969 .

[20]  M. Brock Fenton,et al.  Social behavior of the little brown bat, Myotis lucifugus , 1979, Behavioral Ecology and Sociobiology.

[21]  Nycteris grandis (Nycteridae): an African carnivorous bat , 1981 .

[22]  J. Simmons,et al.  Acoustic imaging in bat sonar: Echolocation signals and the evolution of echolocation , 1980, Journal of comparative physiology.

[23]  D. Griffin,et al.  The importance of atmospheric attenuation for the echolocation of bats (Chiroptera). , 1971, Animal behaviour.

[24]  E. R. Buchler.  The development of flight, foraging, and echolocation in the little brown bat (Myotis lucifugus) , 1980, Behavioral Ecology and Sociobiology.

[25]  J. Fullard,et al.  Detection of certain African, insectivorous bats by sympatric, tympanate moths , 1981, Journal of comparative physiology.

[26]  Gloria Sullivan Caldwell.  Attraction to tropical mixed-species heron flocks: Proximate mechanism and consequences , 2004, Behavioral Ecology and Sociobiology.

[27]  J. Bradbury.  Target discrimination by the echolocating bat Vampyrum spectrum. , 1970, The Journal of experimental zoology.

[28]  R. Barclay.  Night Roosting Behavior of the Little Brown Bat, Myotis lucifugus , 1982 .

[29]  G. Bell,et al.  Habitat use and response to patches of prey by desert insectivorous bats , 1980 .

[30]  T. Kunz,et al.  Night roosting and the nocturnal time budget of the little brown bat, Myotis lucifugus: Effects of reproductive status, prey density, and environmental conditions , 2004, Oecologia.

[31]  J. Krebs.  Colonial Nesting and Social Feeding as Strategies for Exploiting Food Resources in the Great Blue Heron (Ardea Herodias) , 1974 .

[32]  M. Fenton,et al.  Recognition of Species of Insectivorous Bats by Their Echolocation Calls , 1981 .