\nspringerlink.com<\/p>\n
Donald\u00a0R.\u00a0Griffin1 and David\u00a0Thompson1
\n(1)\u00a0
\nThe Rockefeller University, 10021\u00a0New York, New York, USA<\/p>\n
Received: 8\u00a0August\u00a01981\u00a0\u00a0Accepted: 7\u00a0December\u00a01981\u00a0\u00a0
\nSummary\u00a0\u00a0The ability of cave dwelling swiftlets (Collocalia spodiopygius) to detect small cylindrical obstacles by echolocation was tested in a 3×9 m flight chamber. Although there was great individual variability, 6.3 mm obstacles were avoided much more often in total darkness than 1.5 wires (P<0.001). Flash photographs showed that the latter were avoided only by chance (about 50% misses). Obstacles 3.0 mm in diameter were avoided only slightly more often than 1.5 mm wires.
\nEven in the light these swiftlets avoided the obstacles in only about 75% of the trials, probably because gentle touches with the primary feathers caused little discomfort.
\nThe 3.0 and 6.3 mm obstacles tended to be avoided more often on first encounters after they had been shifted horizontally by 10\u201330 cm, probably because the birds became more attentive.
\nReferences
\nFenton MB (1975) Acuity of echolocation in Collocalia hirundinacea (Aves, Apodidae), with comments on the distributions of echolocating swiftlets and Molossid bats. Biotropica 7:1\u20137
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\nGriffin DR (1958) Listening in the dark. Yale University Press, New Haven, CT (reprinted 1974, Dover Publications, New York)
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\nGriffin DR, Suthers RA (1970) Sensitivity of echolocation in cave swiftlets. Biol Bull 129:495\u2013501
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\nGriffin DR, McCue JJG, Grinnell AD (1963) The resistance of bats to jamming. J Exp Zool 152:229\u2013250
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\nHenson OW, Schnitzler H-U (1980) Performance of airborne biosonar systems: II. Vertebrates other than microchiroptera. In: Busnel R-G, Fish JF (eds) Animal sonar systems. Plenum, New York, pp 183\u2013195
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\nJen PH-S, McCarty JK (1978) Bats avoid small moving objects more successfully than stationary ones. Nature 275:743\u2013744
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\nKonishi M, Knudsen EI (1979) The oilbird: hearing and echolocation. Science 204:425\u2013427
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\nMedway L, Pye JD (1977) Echolocation and the systematics of swiftlets, chap 19. In: Stonehouse B, Perrins C (eds) Evolutionary ecology. University Park Press, Baltimore, pp 225\u2013238
\n\u00a0
\nNeuweiler G, Moehres FP (1967) The role of spatial memory in the orientation. In: Busnel R-G (ed) Animal sonar systems, biology and bionics. Laboratoire de Physiologie Acoustique, Jouy-en-Josas, France, pp 129\u2013140
\n\u00a0
\nSmyth DM (1980) Studies on Echolocation in the grey swiftlet, Aerodramus spodiopygius. PhD thesis, James Cook University of North Queensland, Townsville, Australia<\/p>\n","protected":false},"excerpt":{"rendered":"
springerlink.com Donald\u00a0R.\u00a0Griffin1 and David\u00a0Thompson1 (1)\u00a0 The Rockefeller University, 10021\u00a0New York, New York, USA Received: 8\u00a0August\u00a01981\u00a0\u00a0Accepted: 7\u00a0December\u00a01981\u00a0\u00a0 Summary\u00a0\u00a0The ability of cave dwelling swiftlets (Collocalia spodiopygius) to detect small cylindrical obstacles by echolocation was tested in a 3×9 m flight chamber. Although there was great individual variability, 6.3 mm obstacles were avoided much more often in total […]<\/p>\n","protected":false},"author":5,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":[],"categories":[413],"tags":[],"yoast_head":"\n