Great Grey Shrike

The Great Grey Shrike has gained the moniker the Butcher Bird for its rather macabre prac­tice of im­pal­ing its prey on thorn bushes…

Bird Watching (UK) - - Contents - WORDS IAN PAR­SONS

Find out why this bird has earned the nick­name ‘Butcher Bird’

Iwhile think I was about 10 years old when I first saw a Great Grey Shrike. my mem­ory may be a bit vague about my age, it isn’t about the bird. I can still see it in my mind’s eye as if it were yes­ter­day; sit­ting atop a small bat­tered pine tree sur­rounded by a sea of heather. The bird looked im­pres­sive enough, but when some­one said it was also known as the Butcher Bird, and that it im­paled its prey items on thorns, my child­hood imag­i­na­tion roared into life and the bird be­came for­ever fixed in my mem­ory. We don’t get many Great Grey Shrikes win­ter­ing with us in Bri­tain, but we al­ways get some, scat­tered across the coun­try from mid-septem­ber un­til the end of March (some­times stay­ing even later). These are birds not to be missed, so, if you have one near you, make sure you get to see it this month. Great Grey Shrikes are con­spic­u­ous birds, so if there is one win­ter­ing in your area, the like­li­hood is that peo­ple will know about it. Speak­ing and net­work­ing with other lo­cal bird­ers, be it in a hide or on the in­ter­net, is a great way to find out what birds are about. The Great Grey Shrike is the largest shrike found in Eu­rope. It breeds across the north­ern half of the con­ti­nent, with those in the most northerly climes, such as Scan­di­navia, mi­grat­ing in the win­ter. A hand­ful of these mi­grat­ing birds come to Bri­tain, choos­ing to win­ter in a va­ri­ety of habi­tats in­clud­ing heath­land, moor­land, young forestry plan­ta­tions and coastal ar­eas. Even in win­ter, the shrike is ter­ri­to­rial and will of­ten re­turn to the same win­ter­ing site year af­ter year. So, if a site has held a shrike in the past, it is def­i­nitely worth check­ing again. These are medium-sized passer­ines, with a dis­tinc­tive long tail and a rather plump (some say chunky!) body. The head, with

its black eye mask con­trast­ing with soft grey above and white below, is also very no­tice­able, even at a dis­tance. This head is topped off with a short, pow­er­ful­look­ing bill that ends in a fine hooked tip. The wings are black with white flashes in them and the long-rounded tail is also black with white sides. It is an eye-catch­ing bird! While win­ter­ing birds can be found in a va­ri­ety of habi­tats in a va­ri­ety of places, the one com­mon fac­tor to them all is that the sites are open with sev­eral perch points dot­ted about. Great Grey Shrikes like to sit up on these perches, some­times only a me­tre or so in height, from where they can scan around them, look­ing for po­ten­tial food. Fence posts, scrubby trees, tele­graph poles and even over­head wires can all serve as shrike perches, so make sure that you check these out when look­ing for your win­ter­ing shrike. The Great Grey Shrike is a predator, a look at the small but still fearsome bill is enough to tell you that! They eat a wide va­ri­ety of food, ev­ery­thing from bee­tles to small birds are taken, with per­haps their favourite food be­ing small mam­mals, such as voles and mice. Small prey can be de­voured on the spot, but larger prey can present a bit of a prob­lem, they need to be bro­ken up in to small easy-to-swal­low por­tions. Rap­tors, such as the Spar­rowhawk, have the same prob­lem and use their feet and talons to tightly grip they prey, while tear­ing at it with their bill.

Thorny sit­u­a­tion

Shrikes have the bill for this, but they don’t have the feet. In­stead they use the thorns on trees such as the Hawthorn and the spikes of barbed wire to hold their prey items fast. It may seem grue­some to us, but the shrike’s habit of im­pal­ing its prey on to a thorn or a wire is a great ex­am­ple of prob­lem-solv­ing in na­ture. With the item se­cure, the bird can eas­ily tear it into small por­tions. But not all prey items are eaten straight­away, some are stored on these thorns and wires, cre­at­ing larders for the bird to use when the weather turns bad and prey be­comes scarce. It is this habit of us­ing spikes, ei­ther nat­u­ral or man­made, to store and process its prey that has led to the Great Grey Shrike ac­quir­ing the nick­name of Butcher Bird (a name that is also used for other shrike species). But there is more to this butch­ery be­hav­iour than meets the eye. Stud­ies have shown that when feed­ing on in­ver­te­brates such as crick­ets and some bee­tles, the shrikes will al­ways leave these items im­paled in their larders for sev­eral days. Many crick­ets and some bee­tles


pro­duce a chem­i­cal that makes them dis­taste­ful to preda­tors, it is be­lieved that the shrikes have learnt to recog­nise these species and it is these that they leave im­paled for longer. Af­ter a few days, the chem­i­cal starts to wear off, al­low­ing the Shrike to feed on them. Fur­ther stud­ies on this be­hav­iour have also thrown up an in­trigu­ing pos­si­bil­ity that ap­pears to show that shrikes ‘un­der­stand’ the value of food nu­tri­tion. Al­low­ing the prey item to dry out im­proves its nu­tri­tional value, but this has long been thought to be an in­ci­den­tal ef­fect of the shrike’s be­hav­iour and not the cause of it. But it has re­cently been dis­cov­ered that the bird could be de­lib­er­ately dry­ing the food to im­prove its nu­tri­tional value. When try­ing to so­licit a mat­ing from a fe­male, a male shrike will of­ten of­fer the fe­male food as an en­tice­ment and stud­ies show that the male will se­lect a dried piece of food for this, rather than a freshly caught item. More stud­ies are needed, but this be­hav­iour seems to im­ply that the male (and the fe­male) recog­nise the ‘higher value’ of the dried item. The site I saw my first ever Great Grey Shrike on all those years ago is by no means a reg­u­lar haunt of the species, yet it left a very mem­o­rable im­pres­sion on my young mind. This month is a great time to go look­ing for your very own mem­ory!

Even Robins can be vic­tims of Great Grey Shrikes

Shrikes some­times hover over po­ten­tial prey vic­tims!

Yes, an­other Robin awaits con­sump­tion

A shrew im­paled by a Butcher Bird

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