Editing Common tern (section)

===Voice===
Common terns have a wide repertoire of calls, which have a lower pitch than the equivalent calls of Arctic terns. The most distinctive sound is the [[Alarm signal|alarm]] ''KEE-yah'', stressed on the first syllable, in contrast to the second-syllable stress of the Arctic tern. The alarm call doubles up as a warning to intruders, although serious threats evoke a ''kyar'', given as a tern takes flight, and quietens the usually noisy colony while its residents assess the danger.<ref name=hume68/> A down-slurred {{not a typo|''keeur''}} is given when an adult is approaching the nest while carrying a fish, and is possibly used for individual recognition (chicks emerge from hiding when they hear their parents giving this call). Another common call is a ''kip'' uttered during social contact. Other vocalizations include a ''kakakakaka'' when attacking intruders, and a staccato ''kek-kek-kek'' from fighting males.<ref name=hume68>Hume (1993) pp. 68–75.</ref>

Parents and chicks can locate one another by call, and [[sibling]]s also recognise each other's vocalisations from about the twelfth day from hatching, which helps to keep the brood together.<ref name= sibling>{{cite journal | last= Burger | first= Joanna | author2= Gochfeld, Michael | author3= Boarman, William I | year= 1988 | title= Experimental evidence for sibling recognition in Common Terns (''Sterna hirundo'') | journal= Auk | volume= 105 | issue= 1 | pages= 142–148 | jstor= 4087337 | url= http://sora.unm.edu/node/24524 | doi= 10.1093/auk/105.1.142 | access-date= 22 February 2013 | archive-date= 21 October 2020 | archive-url= https://web.archive.org/web/20201021191648/https://sora.unm.edu/node/24524 | url-status= live | url-access= subscription }}</ref><ref name = Stevenson/>