Biodiversity in Action: a Roll Call of Raptors

SPARROWHAWK

Wherever songbirds and pigeons are thriving, there you’ll find sparrowhawks (Accipiter nisus). These small falcons are fast and stealthy ambush predators, most at home around hedgerows and forest-edges where they put natural cover to deadly use.

Sparrowhawks have strong sexual dimorphism and females can be twice the weight of males. Males have barred orange undersides and a 60cm wingspan and mostly predate songbirds. Females have barred grey undersides and an 80cm wingspan and can take woodpigeons.

In the late 20th century, the sparrowhawk was all but extinct in eastern counties due to persecution and pesticide use. Like other native raptors, they’ve bounced back well with improved farming practices and now number around 30,000 pairs.

KESTREL

The kestrel (Falco tinnunculus) is perhaps our most familiar small falcon. This adaptable master hunter will make the most of open ground whether it’s a moor, a field or a motorway verge. Its ability to ride a stiff breeze with its eyes locked on target is endlessly fascinating and its old country name, ‘windhover’, is well earned.

Like the sparrowhawk – to which it is similar in size – the kestrel has recovered well from 20th-century environmental degradation and now numbers around 31,000 pairs.

PEREGRINE FALCON

Far bigger than other British falcons, the powerful peregrine (Falco peregrinus) has a wingspan of up to 1.2m and is dizzyingly fast on the hunt; the highest recorded diving speed is 242mph! Human persecution nearly wiped out British peregrines in the 20th century and it remains a Schedule 1 species.

Peregrines favour moorland and sea cliffs but will hunt east coast wetlands and are known to favour high-rise urban settings with an abundance of pigeons, famously including Lincoln Cathedral. You’d be lucky to see a peregrine at South Ormsby although the chances may be higher than we initially thought. We’re told that peregrines may be roosting at South Thoresby Quarry – only 4km from our doorstep – and that there’s a breeding population in the tall spire of St James’ Church, Louth (there’s a live video feed HERE). Thanks to Alan Hill and Richard Hazel respectively for this intel.

HOBBY

Similar in size to the kestrel but resembling a large swift in profile, the hobby (Falco subbuteo) is a summer visitor to woods and heathland across central, southern and eastern England. Celebrated for its tenacity and agility, the hobby will chase songbirds and large insects across summer meadows and can transfer prey from talons to beak in flight. As with the peregrine, if you spot one of these Schedule 1 birds in our neck of the woods, do tell us.

TAWNY OWL

We’ve installed nesting boxes for both tawny and barn owls with the assistance of expert bird-ringer Jim Lennon, and he shared some insights.

“The tawny owl (Strix aluco)  is bigger and hardier with shorter wings. They’re designed to hunt in small spaces and drop on to prey. Tawnies average 500-600g in weight, compared to 300g for a barnie.

“Tawny owls like a ‘vicarage garden’, a dense, wooded area. They like to hunt songbirds and small mammals in shrubs and flower layers, and they’ll also take young rooks when they’re branching. They’ll get them at dusk and they’ll drop on them rather than chasing.

“Tawny owls have spats in early winter as the youngsters are obliged to find their own territories. You’ll hear the call and response – the male ‘kerwit’ and female ‘whoo’ sounds.  Like some teenagers, they have to be encouraged to leave home and then they don’t move far!”

BARN OWL

“Barn owls (Tyto alba) hunt over more open terrain and glide in. Barnies have offset ears for 3D ranging and a wing profile that reduces noise from flapping. Cut hay meadows in autumn present the most wildlife. They prefer small mammals and it’s rare for them to eat birds. Sometimes they exhibit niche skills. They’re known to brush the tops of reeds to flush prey and I came across one that took starlings from a reed-bed roost.

“Barn owls hate the wet as it reduces their ability to fly. In persistent rain, they’ll shelter in nesting boxes in preference to trees. If you want to encourage barnies, it can be useful to provide both nesting and roosting boxes. They’re built for temperate climates and the UK is right on the edge of their range.”

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