Dogs not welcome if we want to to enjoy the spectacle of returning overwintering birds

After a summer catching the high tide for a swim in Dublin Bay – accompanied by swifts screaming overhead – I’m now waiting for the low tide to walk the undulating sands in search of returning overwintering birds.

From as early as August, they arrive in dribs and drabs – some still with vestiges of breeding plumage – and soon more than 20,000 of them will make North Bull Island their home, while the rest of the bay will be populated by light-bellied Brent geese who’ve flown from Arctic Canada, bar-tailed godwits from northern Europe to western Siberia, and a plethora of other beauties including sanderling, golden plover, redshank, curlew, turnstone, knot and dunlin.

Their return each winter is one of Dublin’s great free spectacles. One thing we could all do while sharing the bay with them is to keep our dogs away, or at the very least, in control on a lead.

In 1897, the naturalist Charles Patten stood before the Dublin Naturalists’ Field Club and read out a list of the birds of Dublin Bay. While doing so, he gave a top tip for anyone heading out to the shore: “Never bring a dog with you.” He bluntly stated what anyone walking the bay today knows: a dog drives the birds away.

Ten years later, the naturalist Alexander Williams described what happened when people ignored Patten’s advice. On the Shelly Banks in Irishtown, little terns and ringed plovers nested among the shells and in summer, Williams wrote, tern chicks ran across the sand “like mice”. But every weekend, cyclists and walkers, “often accompanied by dogs”, visited the bay and raided their nests.

One person who did a lot to protect the bay was Jesuit priest Fr Patrick Kennedy. In 1930, as the Wild Birds Protection Act was being drafted, he persuaded a senator to add a clause allowing bird sanctuaries to be created, and he convinced a hesitant Dublin Corporation to use it. By 1931, North Bull Island became Ireland’s first bird sanctuary, a move, according to Kennedy, that nature lovers might imagine would make the place “sacred and inviolable for evermore”.

They were wrong. In 1949, he wrote an essay, titled Violation of Sanctuary, for the Jesuit journal Studies. There were plans for a cinema, dance halls and a bus road on the island, and shooting had returned to the lagoon. The birds, which had become almost tame under protection, had once again become “shy and wary”. “Birds know the difference between a man with a gun and a man with a pair of field glasses,” Kennedy wrote.

Over the last century, the Bull has lost a lot. Patten recorded little terns, ringed plovers and wheatears breeding; none breed there now. In the 1950s, UCD botanists surveyed the salt marsh and found hares in such abundance that they had worn tracks across it. The last known sighting of hares on the island was in 2016 and dog disturbance is believed to be the main pressure.

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Bull Island is among the country’s most protected places: part of an Unsesco biosphere, a national nature reserve, a Ramsar wetland of international importance, and protected under two EU directives. Bylaws from 1994 require dogs to be kept on leads, but the Irish Wildlife Trust say these laws were not enforced. In 2023, Dublin City Council asked dog owners to keep their pets on short leads in the dunes and to keep them out of the salt marshes and the island’s northern tip altogether. But these are voluntary codes, leaving the conservation rangers hired last year in a weak position: they can only ask, not enforce.

As winter approaches, this matters most. When the tide goes out, birds like curlews and geese must feed constantly to survive. Every time a dog appears, a flock will either take to the air for safety or move away with vigilance, both burning energy it likely cannot spare. To a flock of curlew or oystercatcher, a dog off its lead and a man with a gun look the same: the birds flee.

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Dublin Bay has a long list of protections: it’s an Unesco biosphere and much of it is protected under EU law for its birds and habitats. But if our dogs are allowed to run rampant, what’s the point?

Germany’s Wadden Sea has been a Unesco biosphere since 1990 and it attracts 10 million holiday visitors and 16 million day-trippers every year. Dogs must be kept on a lead at all times. The dunes are closed to them altogether and owners have designated dog beaches. Breaches of the law carry fines of up to €10,000. The rules are clear and are enforced.

For dog owners like me, the rules need to be consistent across the whole bay, clearly marked and enforced. If we know what to expect and the difference it makes to the birds, I believe most of us will comply. For the few who don’t, a steep fine is a fast lesson.

The wintering birds are back and we’re lucky to have them. The pressures they face are immense. Geese that have flown 5,000km to be here shouldn’t be pestered and chased all day by our pet dogs. The authorities should act fast and make one clear rule: dogs on leads.