Getting to grips with gulls

Seagulls – don’t you just love ’em? Or maybe you just hate ’em? Or maybe, like HOT’s Nick Terdre, you have a love/hate relationship with them. Pulled both ways, he thought it was time to find out what seagulls are really like. 

My love/ hate relationship with seagulls goes back to the noughties, when I was living in Stavanger, a small port city on Norway’s west coast. Nearly every day I’d go out for a run in the afternoon, and suddenly I was aware that when gulls saw me coming, they’d start squawking loudly and flock overhead.

On one occasion, one took off from the building on the other side of the road and flew straight down at me, only pulling away when it was quite close. It made me think, suppose it decided on a crash course, and aimed its long beak for my eye – it would penetrate into my brain and I might well be dead.

For the bird it would probably be suicidal, and animals don’t normally take such extreme measures. But the whole situation was very intimidating, and I couldn’t understand why I was being singled out for this treatment – the gulls paid no attention to pedestrians walking along, or cyclists, or vehicles, so why me?

This aggressive behaviour didn’t happen all year round, it seemed to be concentrated in the summer months. I eventually worked out that it must be connected with the nesting period – the birds saw me as a potential threat or predator.

Of course I’m not alone to have found myself the target of gulls’ aggressivity. I remember reading in the paper about a woman attacked by a gull in the street for no apparent reason, who sustained facial injuries requiring hospital treatment. And earlier this year “menacing seagulls the size of large dogs” were denounced in Parliament for “causing havoc across Scotland.”

What makes seagulls tick?

So after moving to Hastings and encountering the same behaviour, if somewhat less aggressive, I decided to try and find out what makes seagulls tick.

A HOT colleague put me in touch with Richard Thompson at RSPCA Mallydams. He did his master’s thesis on gulls, so here was the fount of knowledge I was looking for. The first misconception which Richard corrected when I went to speak to him was the very word seagull – not all gulls live by and make use of the sea, he said, so seagull was not the correct term – I should just call them gulls.

The commonest form of gull in Hastings is the herring gull, but there are other species – for example the lesser black-backed gull and the great black-backed gull, both of which are present here in larger numbers during winter. Another winter visitor is the black-headed gull, smaller than the herring gull, which can be found breeding in Rye Harbour Nature Reserve.

Gulls are long-lived, Richard says – the maximum  age he’s known a gull to live to after being ringed at Mallydams is 18 years and nine months, but the longevity record for a herring gull is 32 years nine months. That longevity indicates that they are a successful species, which in turn means that they know where to find food. They’ve evolved to eat high-protein food, which means they don’t have to eat all the time, they can enjoy downtime. They are intelligent birds which have learned to adapt – for example, to living in urban environments.

Varied menu

So what do gulls eat? A lot more, it transpires, than the chips and ice cream the cheeky ones nab from unsuspecting tourists enjoying an al fresco meal in the Old Town. I didn’t think gulls caught fish but apparently they can shallow-dive and catch fish near the surface. They’ll follow boats such as fishing boats and ferries in the hope of grabing discards. They’ll also follow sea mammals such as whales and dolphins with the same idea.

But basically they are foragers, says Richard – they go searching for a wide variety of comestibles. On the beach they will look for marine invertebrates such as worms, starfish or crabs. If they find a shellfish on the beach they’re clever enough to fly up in the air and drop it on the pebbles to break the shell. Away from the beach they look for terrestrial invertebrates like earthworms, of which they consume a lot.

During the nesting season they’ll take the chicks of other gulls if they can. And by the same token, if they find the chicks of other species unprotected, they will be fair game too.

And as we all know too well, gulls find rich pickings in the food discarded by us humans. Black binbags don’t deter them, they just rip them open with their strong beaks. The advent of wheelie-bins and gull-proof bags for protecting the bin bags has been a boon, though it’s still common enough to find rubbish strewn over the pavement courtesy of gulls and careless or ignorant humans.

Flocks of the birds can also be found at landfill sites, picking through the rubbish for food. Their numbers are thought to have escalated after clean air legislation put an end to the burning of waste, Richard says.

Protected species

Gulls – all kinds – are a protected species. It’s a criminal offence to intentionally injure or kill them or damage or destroy active nests. The level of protection varies according to national estimates of their breeding success. In Hastings, however, there always seem to be plenty of them, no doubt due to the ample food supplies.

According to Richard, their numbers fluctuate quite dramatically during the year. In summer the UK population is roughly estimated at 130,000 pairs, or 260,000 individuals. But in winter that nearly trebles to 730,000 individuals as large numbers of migrants fly in, including great black-backs from Scandinavia.

When spring comes, and the migrants have returned to colder habitats, the domestic residents pair off. They will normally stick with the same partner, but if the pairing doesn’t work, and especially if mating isn’t successful, they will look for a new mate.

Gulls are colony birds, with many pairs nesting in the same area. The advantage of the colony is that, with birds always in attendance, it’s easier to defend than lone nests. And the nests are well away from ground-based predators such as foxes or cats – unless a chick falls out, which is not an unusual occurrence.

However, the greatest danger perhaps comes from other gulls – while they nurture their own offspring, they see one another’s chicks as fair game, so one member of a pair is always advised to stick around and protect the nest.

And then of course there are humans, of whom there is a minority who, irritated by the squawking or the mess they make, will take or make opportunities to attack gulls. Gulls injured by humans account for a significant proportion of the number which end up at Mallydams requiring treatment.

Three eggs is an average clutch, though the number varies. Both parents share the responsibility of finding food. This they store in their crop, regurgitate to the chicks when they reach the nest, and fly off again to fetch more. Herring gulls sport a red spot on either side of their beak which the chicks peck at to show they want food. Moorhens have a similar spot, but it’s maybe strange that it evolved as other species of birds get by very well without it. Outside the nesting season the spot disappears.

Quick developers

The chicks grow very quickly – by seven weeks they’re nearly as big as their parents and ready to fledge. By that time they should be fit and resilient enough to feed themselves, though if they continue to beg for food, the parents are likely to go on feeding them. And in my experience, that is quite common.

The juveniles are mottled brown. They don’t acquire full adult plumage until their fourth year, though they may start to breed earlier. Richard has seen three-year-olds breed.

Herring gulls are quite large animals – adult males weigh up to 1.5 kg and females up to 1.1. With their great wing span – up to 155 cm (from three to nearly five feet) – they are fantastic flyers. During stormy weather they seem to enjoy taking to the air and floating high above, facing into the wind and hardly moving a muscle.

They are capable of flying long distances, though not all of them do; the search for food is one motivation, so a gull which readily satisfies its hunger locally may not feel impelled to go far afield.

But some do. Outside the breeding season some will fly inland, perhaps up to London, or spend time on reservoirs. And some will travel considerably further; Richard mentions one adult gull that was ringed at Mallydams one summer and turned up in Finland, a distance of some 2,000 kms, and another found in Ireland.

Other gulls rehabilitated and ringed at Mallydams have taken a southern route, down through France and Spain to Portugal to spend the winter before returning for the breeding season. Some lesser black-backed gulls fly to Portugal and onto north Africa during the winter period.

Found around the world

Another sign of gulls’ success is that they can be found around the world, except in areas of extreme heat or cold. Types of gull vary somewhat from continent to continent – the American herring gull is slightly different from the European, and the European somewhat different again from the Asian and Russian equivalents.

Historically, too, they have been around a long time, since well before humans, Richard points out. The fossil remains of birds similar to herring gulls have been found as long ago as 23 million years, in the Miocene era. And their predecessors can be traced back more than 100 million years, to well before the mass extinction.

So when a gull gives me that stern piercing look, as if to say, “You looking at me, pal?”, although I’m not inclined to hand over my chips, I do feel I owe it some respect as a member of a highly successful species which has not only survived and thrived through the ages, but also learned to co-exist with humans.

And if one flies overhead squawking indignantly at me as I pass by on my morning run, I’ve learned to live with that too.

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