Cargando…

Oilbirds produce echolocation signals beyond their best hearing range and adjust signal design to natural light conditions

Oilbirds are active at night, foraging for fruits using keen olfaction and extremely light-sensitive eyes, and echolocate as they leave and return to their cavernous roosts. We recorded the echolocation behaviour of wild oilbirds using a multi-microphone array as they entered and exited their roosts...

Descripción completa

Detalles Bibliográficos
Autores principales: Brinkløv, Signe, Elemans, Coen P. H., Ratcliffe, John M.
Formato: Online Artículo Texto
Lenguaje:English
Publicado: The Royal Society Publishing 2017
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5451837/
https://www.ncbi.nlm.nih.gov/pubmed/28573036
http://dx.doi.org/10.1098/rsos.170255
_version_ 1783240257635876864
author Brinkløv, Signe
Elemans, Coen P. H.
Ratcliffe, John M.
author_facet Brinkløv, Signe
Elemans, Coen P. H.
Ratcliffe, John M.
author_sort Brinkløv, Signe
collection PubMed
description Oilbirds are active at night, foraging for fruits using keen olfaction and extremely light-sensitive eyes, and echolocate as they leave and return to their cavernous roosts. We recorded the echolocation behaviour of wild oilbirds using a multi-microphone array as they entered and exited their roosts under different natural light conditions. During echolocation, the birds produced click bursts (CBs) lasting less than 10 ms and consisting of a variable number (2–8) of clicks at 2–3 ms intervals. The CBs have a bandwidth of 7–23 kHz at −6 dB from signal peak frequency. We report on two unique characteristics of this avian echolocation system. First, oilbirds reduce both the energy and number of clicks in their CBs under conditions of clear, moonlit skies, compared with dark, moonless nights. Second, we document a frequency mismatch between the reported best frequency of oilbird hearing (approx. 2 kHz) and the bandwidth of their echolocation CBs. This unusual signal-to-sensory system mismatch probably reflects avian constraints on high-frequency hearing but may still allow oilbirds fine-scale, close-range detail resolution at the upper extreme (approx. 10 kHz) of their presumed hearing range. Alternatively, oilbirds, by an as-yet unknown mechanism, are able to hear frequencies higher than currently appreciated.
format Online
Article
Text
id pubmed-5451837
institution National Center for Biotechnology Information
language English
publishDate 2017
publisher The Royal Society Publishing
record_format MEDLINE/PubMed
spelling pubmed-54518372017-06-01 Oilbirds produce echolocation signals beyond their best hearing range and adjust signal design to natural light conditions Brinkløv, Signe Elemans, Coen P. H. Ratcliffe, John M. R Soc Open Sci Biology (Whole Organism) Oilbirds are active at night, foraging for fruits using keen olfaction and extremely light-sensitive eyes, and echolocate as they leave and return to their cavernous roosts. We recorded the echolocation behaviour of wild oilbirds using a multi-microphone array as they entered and exited their roosts under different natural light conditions. During echolocation, the birds produced click bursts (CBs) lasting less than 10 ms and consisting of a variable number (2–8) of clicks at 2–3 ms intervals. The CBs have a bandwidth of 7–23 kHz at −6 dB from signal peak frequency. We report on two unique characteristics of this avian echolocation system. First, oilbirds reduce both the energy and number of clicks in their CBs under conditions of clear, moonlit skies, compared with dark, moonless nights. Second, we document a frequency mismatch between the reported best frequency of oilbird hearing (approx. 2 kHz) and the bandwidth of their echolocation CBs. This unusual signal-to-sensory system mismatch probably reflects avian constraints on high-frequency hearing but may still allow oilbirds fine-scale, close-range detail resolution at the upper extreme (approx. 10 kHz) of their presumed hearing range. Alternatively, oilbirds, by an as-yet unknown mechanism, are able to hear frequencies higher than currently appreciated. The Royal Society Publishing 2017-05-24 /pmc/articles/PMC5451837/ /pubmed/28573036 http://dx.doi.org/10.1098/rsos.170255 Text en © 2017 The Authors. http://creativecommons.org/licenses/by/4.0/ Published by the Royal Society under the terms of the Creative Commons Attribution License http://creativecommons.org/licenses/by/4.0/, which permits unrestricted use, provided the original author and source are credited.
spellingShingle Biology (Whole Organism)
Brinkløv, Signe
Elemans, Coen P. H.
Ratcliffe, John M.
Oilbirds produce echolocation signals beyond their best hearing range and adjust signal design to natural light conditions
title Oilbirds produce echolocation signals beyond their best hearing range and adjust signal design to natural light conditions
title_full Oilbirds produce echolocation signals beyond their best hearing range and adjust signal design to natural light conditions
title_fullStr Oilbirds produce echolocation signals beyond their best hearing range and adjust signal design to natural light conditions
title_full_unstemmed Oilbirds produce echolocation signals beyond their best hearing range and adjust signal design to natural light conditions
title_short Oilbirds produce echolocation signals beyond their best hearing range and adjust signal design to natural light conditions
title_sort oilbirds produce echolocation signals beyond their best hearing range and adjust signal design to natural light conditions
topic Biology (Whole Organism)
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5451837/
https://www.ncbi.nlm.nih.gov/pubmed/28573036
http://dx.doi.org/10.1098/rsos.170255
work_keys_str_mv AT brinkløvsigne oilbirdsproduceecholocationsignalsbeyondtheirbesthearingrangeandadjustsignaldesigntonaturallightconditions
AT elemanscoenph oilbirdsproduceecholocationsignalsbeyondtheirbesthearingrangeandadjustsignaldesigntonaturallightconditions
AT ratcliffejohnm oilbirdsproduceecholocationsignalsbeyondtheirbesthearingrangeandadjustsignaldesigntonaturallightconditions