This guide is going to look at Kestrel and Merlin as confusion species, which is
most likely to be a problem during the non- breeding season.
Kestrel is a common and familiar falcon found all over the UK in a very wide range of
habitats, from urban areas and farmland right into high and wild ground and mountains.
Merlin is perhaps a less familiar species found principally in the North and West on moorland
and mountains in the breeding season but also likely to be encountered in the lowlands,
in coastal, or even in farmland habitats in winter right around the UK.
Kestrel is probably the most familiar of our raptors; the 'motorway hawk'.
It is a medium sized falcon with longish wings and long tail giving an overall elegant
appearance with light and bouyant flight.
Kestrels feed principally on invertebrates and small mammals and so its hunting technique consists of
'sit and wait', often on a high perch such as a telegraph pole, or by hovering.
In the UK, this hovering is a definitive identifying behaviour of Kestrel.
Once prey has been spotted, Kestrels will often roll sideways and down off the post before
dropping onto the meal.
Kestrels also drop from the hover, often in steps, turning to drop before twisting back
into the wind to hover again before repeating the process.
Again, this behaviour is distinctive.
Both male and female Kestrel show chestnut upperparts with well demarcated dark outer wings.
Both sexes also have a broad black tip to the tail which is barred in females
and silver/grey in males.
The grey head of the male is not particularly obvious except in a close view but all
Kestrels have a dark moustacial stripe.
Merlin is a much smaller falcon, the largest females barely match the smallest male Kestrels.
The tail is square and the wings broad-based accentuating the dumpy, solid impression.
When resting, the birds often perch on the ground, on low posts or rocks and often
look neckless or hunched.
Their main prey is small birds and so the hunting technique is totally different to Kestrel.
The birds fly in a purposeful fashion and never hover.
The best description of their flight is 'dashing'.
When flying normally, flight tends to be low level, using the ground as cover and when actively
hunting, Merlins often disquise themselves by adopting a different flight style.
By using shallow flicking wingbeats, Merlin can look surprisingly like the similarly sized Mistle Thrush.
Perhaps this allows the falcon to get closer to prey before its presence is detected.
Once the chase is on, Merlin are amazingly agile with a furious twisting flight path easily matching
the escape attempts of the prey.
In similar fashion to Kestrels, male Merlins also have a dark outer wing and
black band at the end of the tail (which is also grey) but no Merlin has chestnut back
and wings.
Male Merlin's are slate grey and the female's, dark brown.
Both sexes also have a dark moustacial stripe but the markings on the face give a distinctive
impression of two stripes, one behind the eye and one in front.
Male and female Merlin are similar in size to male and female Sparrowhawks.
The females are dark brown and well marked and the males grey above and rufous below
but in all cases, the falcon shape, pointed wings, habitat and jizz, should prevent confusion.
The other potential confusion species from behind is Peregrine when size isn't apparent.
Peregrine shares the slate grey back, wings and tail with the male Merlin but Peregrine
is a very stocky, bulky bird.
The grey on Peregrine shades gradually to a darker wingtip and they have a highly distinctive
lighter rump and tail base.
We will be returning to Peregrine and other falcons in a future guide.