Summer Visitors

There’s a time towards the beginning of autumn, when I look skywards and realise the summer visitors have gone. The realisation is always tinged with a little sadness. Longer hours of daylight recede, and the summer flowers begin to wane. Conversely, there’s a moment in spring when I see my first visitor of the summer. And this always feels like a celebration. A triumph of nature overcoming the odds to return to our island.

Swallows

A swallow took the prize for being my first sighting this year. Swallows migrate here from Africa, arriving around April and staying until September. The males arrive first, having travelled over 6,000 miles. They take a few days to establish their territory before the arrival of the females. Swallows mate for life and often return to the same nest season after season. This will tend to be in outbuildings such as barns, where they find shelter from the elements, and relative safety from predators.

Larger than the others in their family (house and sand martins) swallows are identifiable by their red throat, blueish feathers, and tail streamers.

Swallows – note the red throat, the very white underside, and the tail streamers

Swallows often perch on telegraph wires. This is particularly noticeable in later months, when they gather to prepare for their migration back to Africa.

Martins

House and sand martins are part of the same family as swallows. I spent hours at the side of the South Tyne a few years ago, watching sand martins, the smallest of the three. With brown upper feathers, and creamy underside feathers, they also have a brown bar across the top of the chest.

Sand martins don’t build a nest, instead burrowing into sandy or earth banks. The pictures show sand martins perched and flying, and others waiting in their burrows. The brown bar across the chest is visible.

House martins build similar cup shaped mud nests to those of swallows, but usually on the outside of buildings. They have a forked tail, without the streamers, are blueish black on the upper, and have a white underbelly. As seen on the photo which follows, they also have a white rump, just before the tail feathers start.

House martin – image by Dr. Georg Wietschorke from Pixabay

Swifts

Swifts migrate to and from Africa, and usually only spend around three months in the UK. Arriving in May, they are sometimes on their way again by the end of July. They rely on warmth to supply the flying insects they feed on, which limits the length of their stay. Swifts are brown with a white throat. They tend to look black when flying.

The only time swifts land is when they visit their nests, which are built in tall buildings, such as church towers. The rest of their time, including sleeping, is spent on the wing. It is thought that when swifts sleep, the two hemispheres of their brain take it in turns to rest. All while the bird is circling at heights of up to 30,000 feet!

Swifts cannot roost overnight, so they travel quickly when they migrate. One bird was tracked as taking just five days to travel over 3,000 miles from West Africa back to the UK.

Swift – image by TheOtherKev from Pixabay

Although swallows, martins, and swifts look similar, the swift is related more closely to the hummingbird. Swallows and martins are closer to kingfishers. The birds are examples of convergent evolution. This is when unrelated species develop similar physical traits to adapt to their shared environment. In the case of swallows and swifts, this separation in evolution took place about 85 million years ago. To put that into some sort of perspective, it’s the time period when Tyrannosaurus Rex lived.

Further Information

The Wildlife Trusts have a helpful guide on identifying swallows, house martins, sand martins, and swifts. There’s a useful article on the RSPB website which discusses identification, and how we can help the birds.

This is particularly important when considering that the number of swifts declined by over 50% from 1995 to 2015. A German study found a 76% decline in flying insects from 1989 to 2017. The overlap between the two can be no coincidence. Swifts rely on flying insects for food. Add this decline to the loss of nesting habitat, and life looks even more difficult for the swifts. In 2021, they were added to the Red List in the UK Conservation Report. This is the highest level of conservation priority, and identifies species which need urgent help to arrest a global decline in numbers. It’s up to all of us to take whatever action we can to preserve the environment, and ensure our summer visitors are not consigned to history.