As spring settles in, another group of long‑distance travellers begins to arrive on our coastline – terns. Alana, from our monitoring team, has put together this second instalment in her breeding‑season guide, this time focusing on the terns that return each year from Africa to breed.
The start of the breeding bird season truly commences with the arrival of the UK’s diverse selection of tern species.
Early arrivals: Sandwich terns
The first to arrive on the Solent’s shorelines is the Sandwich tern, the Solent’s largest breeding terns. They arrive early, from mid-March to early April, quickly establishing their nesting areas among the black‑headed gull colonies. Sandwich terns are generally less aggressive than other terns, and the gulls’ more assertive behaviour offers useful protection.
These handsome terns, adorned with a head tuft of black fluff, are dramatic to watch from afar – especially during their aerial courtship, when pairs lift into the sky before plunging down together in tight, coordinated dives. By late April they will be making their scrapes, laying eggs, and beginning to incubate them, with chicks hatching towards the end of May and fledging from late June onwards.
Sandwich terns
Little terns: small, agile and fiercely protective
Shortly after the Sandwich terns settle in, little terns arrive. They may be the smallest of our breeding terns, but they are among the most determined parents on the coastline when defending their young from predators like other gulls, crows, kestrels and even foxes.
Little terns reach the Solent from early to mid‑April, favouring sandy and shingle beaches for their nesting sites. Their courtship displays involve nimble dances starting with aerial displays while calling and carrying fish. If a male’s aerial display catches the attention of a female, she will follow him into the air to join in the aerial acrobatics. When they both land, you might also see the male shimmying up to the female with a fish dangling in its beak – with which he might smack her on the head as a final offering. It’s up to her whether she accepts or declines this romantic gesture.
A little tern
After mating, nesting can begin as early as the start of May, with chicks hatching in June. Because their nests sit directly on the shingle, they are vulnerable to being washed away by high spring tides, so second attempts are common if the first one fails early in the early season.
Little tern eggs and chicks are vulnerable to predation and human disturbance and are extremely well camouflaged, making them almost invisible against the shingle on which they nest. This makes it particularly important for us to keep a close look out for them in areas where they nest, to stick to marked paths, and to follow requests on signs, so that we give them the best chance of a successful breeding season.
Little tern parents are renowned for staying close to their colony when feeding their chicks. When threatened, adults will swarm together in coordinated dive‑bombing runs – make sure to give them a wide berth or you’ll quickly learn just how assertive a little tern can be.
Common terns: the colony defenders
By mid‑April, the common terns arrive, their sharp “kyar‑kyar‑kyar” calls carrying across the water. Medium‑sized and highly protective, they are known for defending their colonies with impressive determination – another enthusiastic dive-bombing tern species. Many people who act as wardens at little tern nesting sites quietly hope a few common terns will join each year – to fortify the defensive capabilities of the little tern colony and keep predators at bay.
Common terns begin laying their eggs in scrapes in May, with chicks hatching from mid‑June and fledging by mid‑July. The Solent’s Special Protection Areas provide vital habitat for them, offering safe nesting grounds and rich feeding areas throughout the summer.
A common tern hovers in the air
A season of activity
After this flurry of activity, tern colonies begin to quieten from August onwards – if everything has gone well, they won’t need to lay a second clutch in a further attempt to successfully rear young.
Like our breeding gulls, terns are devoted and highly protective parents, and who will seize any opportunity to show predators and human disturbance exactly who is the boss of the beaches on the Solent’s coastline.
