Swift by nature

Local survey ongoing on migratory bird

“It really is luck,” says Helen Taylor, explaining the difficulty of identifying swift nest sites.

Helen is surveying swift numbers in towns and villages around West Cavan, and last Wednesday evening she was joined by a group of about 40 people for a stroll around Cavan Town to discuss this most thrilling of migratory birds.

The difficulty in locating nest sites is due to the lightning speed of the bird.

“A lot of it is just luck if you see a swift go into his nest because he flies at just over 111km/hr and he enters his nest at just under 50km/hr,” says Helen as “oohs” of wonder emanate from the group.

“Swift by name,” one woman quips.

“Often it’s just a flicker of grey or black you’ll see,” Helen says. “Then you study the building to see it coming out. Even when you know there’s a swift in there, you only need to look away for a second and you’ve missed him going.

“So finding the nests are quite difficult.”

However it’s worth the effort as Helen is trying to establish a baseline survey for Cavan Town and elsewhere.

The work is ongoing, but her interim report shows that so far she has identified 112 sites across six of eight towns/villages surveyed. This work follows last year’s survey in East Cavan where 180 swift nests were confirmed across 10 of 13 towns/villages surveyed. Cootehill topped the swift charts in the east with 33 sites.

This baseline will then be used for future reference to assess the strength of the local population.

“They are in serious decline,” she reports of the national figure for swifts. “Major decline. There has been a 69% decline between the years of 1998 and 2023, and they are still declining now.

“And the decline is mainly because of loss of nesting sites.”

Nest sites are the chief concern for County Cavan too, as given the abundance of lakes, it is assumed there is enough insects to sustain them.

The walk starts on Farnham Street with a wealth of heritage buildings lining each side of the street. Little nooks in the stonework worn by time accommodate the birds during their short season of mating and rearing chicks.

“They’re not here for long,” says Helen. “They come at the end of April, early May and they will be gone by end of July, early August.”

In those three months they rear one brood of, ideally two chicks, but occasionally a smaller third.

“They are one of Ireland’s shortest nesting migratory birds and they have the longest migrations - they are really an incredible species of bird, they are so unique,” lauds Helen.

Sadly for swifts - and other birds - houses built to modern standards with plastic soffits and fascias present less nesting opportunities. This is unfortunate because the birds make for ideal lodgers. Often property owners have no idea they are playing host to swifts.

“They’re very clean birds, all they do is make a bit of noise,” accepts Helen. That noise is the best way to identify them.

“Swifts scream. They do everything to the extreme. So when they come in you will a really high pitch scream. The scream is not one bird, it’s two birds. The scream is a duet between two birds. This has only been found out with good audio recording.”

Pairs of swifts migrate Africa separately but find the same partner and the same nest site each year through the screams.

“At the end of that scream there is a little noise - that we can’t hear - which is individual to the birds. And that’s the two birds finding each other.”

Viewing one gap in a wall on Thomas Ashe Street where opportunistic swifts set up nest, Helen suspects the cavity might be too small for both parents as the chicks mature.

“One adult will have to sleep in the sky - now they are well used to sleeping in the sky, but when they finish feeding their chicks they have to get back to Africa. So it would be ideal if we could provide the perfect box size.”

Size is a factor too when it comes to the chicks fledging.

“Swifts need space. Swift chicks have to drop out of a nest - and they do drop - they drop first and then they start to fly. So before they come out of the nest they have to have room to do press ups. They press up and down on their wings because they have to exercise their wings and build their muscles up.

“So sometimes the swift will get into a space like that and everything’s going great but there’s no room to do the press ups and when they drop out they are too week to fly,” she explains.

Offering perfect dimensions and assurance of permanency swift bricks are an ideal, and discrete, solution. The swift bricks at the Ozanam Centre in River Street appear to be occupied.

In the course of the one hour talk Helen shares amazing insights into the bird such as they can fly as high as jet planes to avoid the impacts of stormy weather, when traversing the Sahara Desert they don’t eat or drink for four days, and if birds in Ireland are unable to find food for their chicks, they will simply zoom across to France to collect a bolus of food - approximately 1,000 insects. To avoid starving while their parents are away, the chicks can go into a torpor, a state of semi-hibernation.

Much of this information has been gleaned in recent years with cameras in nest boxes and specialist tracking devices, attached by trained vets under licence.

“That’s how much a swift weighs,” she says handing around a Cadbury’s Creme Egg. “And the tracker they put on a swift’s back is 5g. Proportionally it’s like me carrying a stone to Africa and back.”

Nevertheless she is in favour of the research as conservationists need information if they are going to secure the future of swift populations.

“I’d say Cavan Town is going to come out very well. It’s not just about food either, it’s about the nesting sites, but Cavan Town has nice old buildings too - in the interim report Cavan town had 50 nest sites - that’s good.”