The NHBS Guide to Swifts, Swallows and Martins Identification

Swifts, swallows and martins are migratory birds, spending the winters in Africa before flying around 3,400 miles to spend summer in the UK. While they are here they spend their days soaring high and feasting on the abundance of flying insects. Their arrival, for many of us, marks the end of winter and announces the arrival of spring and summer.

Although swifts, swallows and martins share some characteristics, they are, upon closer inspection, markedly different. They are roughly similar in size and shape, which can make them difficult to discern between, especially when flying high in the sky. However, as you begin to look closely at their appearance, flight, nesting behaviour and other key characteristics, it is relatively easy to distinguish between them.

Below we share our top tips for identifying swifts, swallows and martins. In this article we have focused on the below species as they are all common and widespread in the UK:

Common swift (Apus apus)
Barn swallow (Hirundo rustica)
Common house martin (Delichon urbicum)
Sand martin (Riparia riparia)

How to identify swifts

Swifts are amazing birds – they are the longest continually-flying species, spending up to 10 months in the air without landing. They eat, drink, sleep, and mate while flying, only landing to breed. They are almost never seen perching.

Key identification features:

Crescent-shaped, long, curving wings
Forked tail which is much shorter and stouter than the tail of a swallow
Dark brown all over with a small pale patch on their throat, but often appear black against the sky
Screaming piercing call

When to spot them in the UK: April to September

How to identify swallows

Image by Vincent van Zalinge via Unsplash

Swallows are small colourful birds. They are known for their agility as they feed on insects while on the wing. They can often be found flying low to the ground over farmland and open pastures, particularly near water where there are lots of insects. In late summer they can be spotted perching together on telephone wires and power lines, readying themselves to migrate to Africa for the winter.

Key identification features:

Glossy blue upper parts, creamy-white under parts
Red throat and dark red forehead, but from a distance their whole head may appear dark
Long forked tail
They tend to nest in barns, lean-tos and other outbuildings, where they build cup-shaped nests of mud
Chattering call
Can be seen perching on telephone wires or wire fencing

When to spot them in the UK: March to October

How to identify house martins

House martins are commonly found in towns and villages, as well as in agricultural areas. They are one of the last of our summer migrants to depart in the autumn. They only eat while on the wing, catching insects as they fly. Their mud cup nests are usually spotted below the eaves of buildings.

Key identification features:

Small birds with glossy blue-black upper parts and pure white under parts
Distinctive white rump, short forked tail and white feathers covering its legs and toes
Shorter wings than swifts or swallows

When to spot them in the UK: April to October

How to identify sand martins

Sand martins are the smallest of all the European hirundines and one of the first spring migrants to appear. They are agile fliers, feeding mainly over water. They breed in colonies of up to 1000 pairs. Unique to sand martins, these birds burrow holes into sandy, dry vertical banks in sand pits, gravel pits, riverbanks, lakes, streams, railway cuttings, and even in drainpipes in walls and holes in brickwork.

Key identification features:

Dark brown upper parts, with pale tipped feathers. Upper wings, tails and flight feathers are dark brown
Under parts are white with a distinctive brown band across the breast separating the white throat from the white belly
Breast band on young sand martins is less visible and their necks and chins are a reddish brown
Short legs and feet which are dark brown or black
Short forked tail
Tend to swirl and flap rather than glide, and can be found mainly over water

When to spot them in the UK: March to October