Alarm calls, by Michelle Dunn

Your Chickens - - Contents -

Chick­ens have the mis­for­tune to be liked by pretty much ev­ery preda­tor in Bri­tain. I don’t mean liked in a “do come round for tea and cake” sort of way, I mean liked as in ‘con­sid­ered good to eat’ kind of way. Look­ing at a do­mes­tic chicken, it is hard to be­lieve that they could sur­vive in the wild for five min­utes. And yet chick­ens have quite a so­phis­ti­cated sys­tem of de­fence.

Vig­i­lance is the first strat­egy. In a group of chick­ens there is al­ways one with its head up, look­ing for dan­ger. Each one looks up for a few sec­onds be­fore re­turn­ing to what it was do­ing, but at any one time there may be up to three chick­ens look­ing around for dan­ger.

When dan­ger is spot­ted, chick­ens have a com­pli­cated sys­tem of alarm calls. If there is a cock­erel, he is usu­ally re­spon­si­ble for mak­ing the calls. He has a sharp, high­pitched call if the dan­ger is from the air (a goshawk or pere­grine, for ex­am­ple) and an ag­i­tated cluck­ing if the preda­tor is on the ground (a fox or weasel, per­haps). There is also a call if the chick­ens are ac­tu­ally un­der at­tack — ba­si­cally a pan­icky ‘aargh’.

Chick­ens know from a very early age what to do in re­sponse to these calls. If the aerial alarm call sounds, they will freeze if they are in the open, or dash for cover if there is un­der­growth nearby. When the ground alarm call sounds, chick­ens stand up straight to try and see the preda­tor and will of­ten fly onto trees or roosts. If the at­tack call sounds then they dash for cover of any sort and of­ten fly into trees if any are avail­able.

Of course, loudly shout­ing an alarm is ef­fec­tively say­ing to the preda­tor, “Look at me, I’m over here,” which is not a good sur­vival strat­egy. So chick­ens as­sess the sit­u­a­tion be­fore they call. If a cock­erel has hens around him, he will sound the alarm. If he is sur­rounded by other cock­erels, he may well just freeze. Sim­i­larly, mother hens will call an alarm to their chicks, but young hens with­out chicks may make a mum­bling noise to alert the older hens to the dan­ger. The dom­i­nant birds in a flock then of­ten screech a warn­ing to­gether, which alerts the rest of the flock to dan­ger and con­fuses the preda­tor.

Chick­ens will fly as high as they can to avoid dan­ger on the ground

This young chick has flown into a tree fol­low­ing an at­tack by a fox cub IN­SET: Spar­rowhawks fly­ing over­head trig­ger the ‘aerial dan­ger’ alarm call

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