Editing Bearded seal (section)

== Vocalization ==
The vocalizations produced by the bearded seal are unique, possibly because their [[trachea]] is different from that of other Northern Pacific [[Earless seal|phocids]]. A majority of the rings in the trachea are incomplete with only a membrane attaching the two ends.<ref name=":2">{{Cite web|url=https://www.boem.gov/ESPIS/0/312.pdf|title=Natural History and Ecology of the Bearded Seal, Erignathus Barbatus|last=Burns|first=John J.|date=May 1979}}{{Dead link|date=June 2020 |bot=InternetArchiveBot |fix-attempted=yes }}</ref>

[[File:Svalbard_Sample_for_Wiki.ogg|thumb|Sample of underwater bearded seal vocalizations taken using a hydrophone]]The sounds of the bearded seal usually consist of a long [[Oscillation|oscillating]] trill lasting for a minute or more followed by a short, deep moan. This "song" is often repeated frequently.<ref name=":2" /> The number of call types within a population can vary geographically, with four types found in Svalbard and eleven in the Western Canadian Arctic. The most frequent sounds are trills, moans, and sweeps. A sweep can be compared to a short trill.<ref name=":0">{{Cite journal|last1=Risch|first1=Denise|last2=Clark|first2=Christopher W.|last3=Corkeron|first3=Peter J.|last4=Elepfandt|first4=Andreas|last5=Kovacs|first5=Kit M.|last6=Lydersen|first6=Christian|last7=Stirling|first7=Ian|last8=Van Parijs|first8=Sofie M.|date=May 2007|title=Vocalizations of male bearded seals, Erignathus barbatus: classification and geographical variation|journal=Animal Behaviour|volume=73|issue=5|pages=747–762|doi=10.1016/j.anbehav.2006.06.012|s2cid=53187110|issn=0003-3472}}</ref>

Bearded seals produce distinct trills from late March to late June, with a decline in [[rhythm]]icity in late May and June. This timeline coincides with their breeding and pupping season, which is from April to May. The repetitive and transmittable nature of bearded seal trills leads researchers to believe that they are utilized for communication, likely during [[Courtship display|courtship]] and breeding.<ref name=":1">{{Cite journal|last1=Cleator|first1=Holly J.|last2=Stirling|first2=Ian|last3=Smith|first3=T. G.|date=5 July 1989|title=Underwater vocalizations of the bearded seal (Erignathus barbatus)|journal=Canadian Journal of Zoology|volume=67|issue=8|pages=1900–1910|doi=10.1139/z89-272|bibcode=1989CaJZ...67.1900C |issn=0008-4301}}</ref> Males use these sounds to establish mating territories and communicate their fitness,<ref name=":0" /> but it is likely that females produce these sounds as well.<ref name=":1" />

Underwater, bearded seal trills can be heard from a distance of over {{convert|30|km|abbr=on}}, with some types of sounds traveling farther than others. This makes it possible for one animal to communicate with another animal that is far away, although acoustic degradation does occur as the sound passes through the environment. A seal must produce a trill with a [[Sound pressure|sound-pressure]] of at least 100&nbsp;[[Decibel|dB]] at 1 m in order for the sound to propagate 30&nbsp;km, meaning that bearded seals can likely produce sounds at this level.<ref name=":1" />[[Image:beardedseal2.jpg|thumb|Bearded seal on ice, [[Svalbard]]]]