In recent days, I have noticed flurries of small twigs, moss, and strands of pampas grass being dropped on a particular part of my decking. Since the detective gene runs through me like the word Brighton in a stick of pink rock, I soon deduced birds were building a nest above, somewhere between the house’s gutter and roof. But which birds? I watched out for the busy avian porters of sticks and moss, and was absurdly pleased to recognise them as starlings.

There are many garden birds I recognise. It’s not that hard to name blackbirds, thrushes, robins, wrens, and my nesting starlings. But apart from cuckoos and corncrakes – and the ubiquitous urban pigeons – I don’t think there is a single birdsong or call I’d be able to identify with assurance. Yet of all the consistent background sounds in my day, birdsong is the loveliest and also the most mysterious.

There’s an app for that, of course. Not just one, but several that record and identify birdsong and calls. I eventually downloaded one on my iPhone this week, BirdSongID.

When you open the app, which covers birds found in Britain and Ireland, it gives you a gallery of different families of birds. Some of these have several members, such as "Thrushes", under which are the robin, blackbird, song thrush, mistle thrush and one I'd never heard of, the fieldfare. Mind you, along with the familiar names of kingfishers and plovers and swallows, the app also lists a "ring-necked parakeet" under "parrots" – not a species I thought common to these islands.

The real interactive magic of the app however, is its record-and-identify function. Press the red button to make a 30-second recording, and then press “automatic recognition”. If the recording is of good quality, you get a list of the birds the app has picked up in the recording, starting with the most vocal, by percentages. It gives you a picture of the bird along with its percentage in the sound mix.

I first try the app walking along Rathgar Road in Dublin at 9am. It’s a long road I haven’t been on for a while, constantly busy with traffic, much of it buses. I have low expectations of getting any audio of good quality. I stop under trees, and hit record, while a bus whizzes past. Less than a minute later, I am gaping at my phone. Under all that urban noise, the birds are singing, and one of them – the top-rated, at 74 per cent – is a curlew.

I associate curlews with water and countryside, not suburban Dublin. Could the app be wrong? I am doubting its ability to identify what I cannot. I do what I do these days when I want an instant answer: I ask Twitter if it is possible to hear a curlew in Dublin. Yes, a reply comes, “I hear them all the time down at the Bull Wall”.

Slow progress
It takes me almost an hour to walk 100m down Rathgar Road. I keep stopping to record, press automatic recognition, and marvel at the many different birds that are singing in the trees and gardens all around. I take screenshots of the results of what I am hearing.

After the curlew, the next recording shows up songs from robins, nightingales, blackbirds and song thrushes. The app even distinguishes between songs and calls (who knew there was a difference?), and, on this recording, the blackbird is both singing and calling.

Back in my garden, I make more recordings. There is a large lilac tree at the end of my garden, currently in full glorious purple bloom. It’s a haven for birds, which are constantly darting through its many branches. I just have no idea which birds. I think vaguely that they might be sparrows.

As it turns out, they are sparrows, but there are also dunnocks (listed under “accentors”, swifts, lapwings, and blackbirds. After a while, I begin to play the app’s recording of various birds, so that I can match them with what I have been recording myself, and try to identify, for example, a blackbird’s song.

I still can’t positively identify the song of a blackbird, or the call of a lapwing, or even tell you for sure what the dunnocks that apparently inhabit my lilac tree look like. But I’m learning.

The only downside of this marvellous app is that it has made me even more addicted to my phone than I already am. Is there an app for that?

Eric Dempsey's Finding Birds in Ireland has just been published by Gill and Macmillan. birdsireland.com, birdwatchireland.ie