The art of small raptor identification can cause confusion until you get familiar with their shapes and habits. We all know a hovering bird by the roadside will be a kestrel, but are less sure when we see something soaring around at height. Getting to grips with a few key features will help a lot towards nailing that ID. We’ll deal with the three most likely to be encountered, especially with summer just around the corner; kestrel, sparrowhawk and hobby. We have other small raptors within the UK such as merlin and occasionally exotic visitors from the Continent, but for the purposes of this guide I think we can safely concentrate on those three widespread and relatively common species. Here we go then, but first a general overview.
The most familiar and once most common bird of prey in the country. It is still a frequently encountered predator, especially along the verges of major roads and open fields where it hovers on quivering wings with motionless head in search of voles and mice, its main prey items. Kestrels are traditionally associated with open countryside which is not intensively farmed, but are nowadays equally at home in towns and cities. I’ve had them hunting birds on the feeders in my suburban garden demonstrating their opportunistic nature. They are basically a brick red colouration and have a typical falcon shape of slender body, slim, sharply pointed wings and strong facial patterning. Of course, this is all very well when they are hovering or when you have good light, but when they are up in the air or flying fast against a bright background it may not always be possible to see these diagnostic pointers. Kestrels nest in cavities in trees and buildings, open nest boxes, old crows’ nests and sometimes even on the ground. After a period of decline, they now seem to be bouncing back to something like their old population which together with their conspicuous hunting methods makes them the most likely of these three species to be seen.
Sparrowhawks suffered a period of great decline during the mid-20th century. This was primarily due to pesticides accumulating in the food chain and having the effect of thinning their egg shells resulting in poor breeding success. After certain chemicals were banned and attitudes enlightened, their recovery began in the 1980s. Happily they are now back to something like their former population levels and once again one of our commonest birds of prey. They are master hunters of small and medium sized birds; agile, fast and deadly. Gardens provide a happy hunting ground where they will prey on birds attracted to garden feeders and will tackle collared doves and woodpigeons with relish. Their hunting methods are to utilise features of their territory, which they will know intimately, to ambush birds that they will catch in mid-air. They seldom attack grounded birds, but will easily pluck a perching bird from the top of a hedge. Read more about some close encounters here. Sparrowhawks are generally grey in colour with broad, rounded wings. They will often be seen soaring or flying over their territory with a distinctive flight of a series of rapid wingbeats followed by a period of gliding. Any greyish bird of prey seen feasting on a bird in your garden will be a sparrowhawk. Female sparrowhawks are larger than males and can therefore deal with larger prey items. They breed in woodland.
Until perhaps the 1980s hobbies were birds only to be found in the southern counties of the UK. Since that time, possibly as a result of a warming climate, it has expanded its range to become a familiar summer visitor. Birds arrive during April and will then gather at favoured refuelling points to feast on emerging airborne insects such as dragonflies (a favoured prey item), or St Mark’s flies. Impressive counts of over 50 are now regularly recorded at RSPB Lakenheath Fen in Suffolk. They are supremely agile hunters with amazing eyesight. I’ve watched one close its wings and home in on a dragonfly from over 100 metres away. They will fly low and fast in pursuit of these insects but will also often hunt more leisurely at considerable height when they become quite inconspicuous. They are also predators of bats and small birds, even swifts, which have developed a specific alarm call to warn others of a hobby’s approach. When you learn this you will always know to look up and scan the skies for one of these beauties. I‘ve watched an adult hobby repeatedly catch a bat and release it on high in order to teach its offspring how to hunt. Seems cruel, but it was nonetheless fascinating. These falcons are built for speed with long, slim, sharply pointed wings. They are slate grey in colour with quite distinctive underside markings – assuming you can get a good view. Hobbies are birds of fen, marsh and wet heathland and become very secretive in the breeding season. They normally nest in an abandoned crows’ nest or similar.
Firstly let’s look at the basic soaring profiles:
Sparrowhawk. At times these can look as though the leading edge of the wing is almost straight with no marked inward curve towards the join with the body. The wings are broad, blunt and relatively short – ideal for twisting and turning in dense woodland.
Kestrel. Typical falcon shape. Wings long, thin and pointed. Note the sharp inward cut of the wings as they join the body.
Hobby. Even slimmer and more pointed wings, ideal for fast moving pursuit of aerial prey.
Now we can look at some more specific features:
Sparrowhawk. A) Broad, evenly barred tail. B) Broad straight wing join with underwing and underbelly evenly barred. C) Fingered primaries on broad, blunt wing tips.
Kestrel. A) Plain tail ending in a broad solid black band. B) Sharp inward wing join with underwing whitish along leading edge becoming more densely barred towards wingtips. Underbelly moderately streaked. C) Pointed wing tips with less obvious primary ‘fingers’
Hobby. A) Densely barred tail. B) Densely black-streaked underwing and underbelly. C) Sharply pointed wingtips, minimal primary ‘fingers’
Next some differences between sexes and young birds:
Sparrowhawk. 1st winter female pictured in Jan 2019 and hatching the previous year. A) Chevron breast and underbelly markings. B) Brown back with light edges to feathers. Note the yellow eye which often chages to orange sometime between the 2nd and 3rd year.
Sparrowhawk. Adult male. Blue-grey feathering, chestnut cheeks with rufous banding on breast. Eye is a deeper orange which probably denotes a bird 2-3 years old at least.
Sparrowhawk. A soaring pair. The thing to note here is the size difference between female (top) and male (bottom).
Kestrel. Female. Note A) Heavily barred upperwing over brick red general colour, and B) streaked brick red head.
Kestrel. Male. Note A) Grey head, and B) Much plainer, brick red upper side colouration.
Kestrel. A female showing well the very slim, upright profile and well marked upper side and head.
Kestrel. A male showing the grey head and generally much cleaner upper side colouration
Hobby. An adult displaying A) Bright orange-red ‘trousers’ covering the thigh area, B) Well defined moustachial stripe typical of falcons, and C) Heavily streaked underside.
Hobby. 2nd year bird showing buff coloured vent.
And lastly some hunting techniques:
Kestrel demonstrating hovering technique
Kestrel with kill – a short-tailed field vole I believe. Note again A) Relatively clean underwing getting more heavily barred towards wing tips, and B) Typical falcon moustachial stripe
Hobby catching insect mid air which it will then devour on the wing
Hobby again having caught a flying insect.
I hope that goes some way towards helping with small raptor identification. Any feedback would be most welcome. If you like the article please visit the rest of the website and/or like our Facebook page.