Swallow, swifts and house martins are a common sight during summer, but they can be difficult to tell apart.
Here is a simple guide to telling the difference between these three common summer visitors and the rarer sand martin.
The swallow when stationary is very distinctive; with its shiny blue/black colouring, bright red chin and forehead and white underside, it looks like nothing else. However, on the wing, you can’t always see the colours. The key feature is the tail; swallows have very long streamers on their tails to give them great manoeuvrability near the ground or water and around obstacles such as grazing animals. They also have a much more relaxed flight than the others, flying in purposeful straight lines.
The house martin is blue/black with an off-white underside. They are stockier than the others and feed higher with frequent changes of direction creating a much more erratic flight pattern. Their nests are commonplace in our towns and cities, tucked up beneath the eaves before houses they would nest on cliffs and some house martins still do. After fledging the young are still fed by their parents either sat on wires or on the wing.
The sand martin is light brown with an off-white underside and a brown band across the breast. They appear less confident when flying and seem to dash. They are the smallest of these birds, and nest inside tunnels dug within sandbanks and cliffs. They nest in large colonies which offer a certain amount of protection from predators.
The three birds mentioned above are collectively known as the hirundine. They can all be seen perched on wires in late summer, preparing to journey to Africa where they winter. You may also see swallows and sand martins roosting in reed beds forming large flocks as they descend to roost at dusk. Their main predator is the Eurasian hobby.
The swift is larger than the hirundine; they have exceptionally long primary feathers and short inner wing which create the familiar crescent shape wingspan which is ideal for rapid and sustained flight. They are solidly black and hold their wings stiff in flight only flapping from the shoulder. At about a month old, the chicks do ‘press-ups’ in the nest, lifting themselves up by pushing down on their wings, probably to strengthen their wings. By the time they are ready to go, they can hold their bodies clear of the ground like this for several seconds. As soon as they fledge they head south, without waiting for their parents, they may then remain on the wing for two or three years without perching. Rather than roosting like other birds, non-breeding swifts sleep on the wing; they fly up high and enter a state of semi-consciousness; breeding pairs will sleep in the nest. In flight, its forked tail is closed for extra proficiency. Swifts cannot feed in wet weather in the UK, so they fly around storms in order to locate dry areas; they are the only UK bird to do this. Contrastingly in Africa, the same swifts will head for the rain, due to there being more insects in the air on rainy days.
Also, check out the British Trust for Ornithology youtube video:
If you’re interested in what else nature gets up to throughout the year, why not read our Bat Diary!?