Nocmig is the new science of recording migrating birds at night, you can try it where every you live, although some places may be better than others. I have been recording at night since 2014 in the south west of England and have on occasions recorded a number of species moving at night, including greenshank, whimbrel, grey heron and Canada geese, and what are moorhens doing fly around woods in the middle of the night in May?
Nocmig is taking off, and is producing some very interesting scientific results.You don't have to live near the coast to be on migration route, birds often migrate on a broad front so you have a possibility of recording all most anything flying over your chosen recording location. To start nocmig recording, all you need is a recorder and a microphone, (see nocmig blog below). Set your recording gear up facing up into the sky at your chosen location at dusk and start recording, leave it running all night then retrieve it in the morning. Some recordists prefer to use a parabolic reflector as this increases the signal, but it also reduces the microphone recording width. You could also use gun mics like the Sennheiser ME66, or similar. One thing you will need to do is to your protect kit against is the weather. Wind is the biggest enemy of the wildlife sound recordist, having a decent windshield around your mic will give you much cleaner recordings without the constant base rumble of the wind. The other issue is rain or dew, protecting your recorder is imperative. I have found placing it in an army canvas bags serves very well.
Once you have your recording you need to analyse it using software that displays your recording in a spectrogram, this enables you to easily see any calls made by passing birds without the need to listen to hours of recording. Most recordist start by using Audicity https://www.audacityteam.org/download/ which is free and is cross platform (works on a Mac, Windows and Linux operating systems). There are other applications that will also display recordings as a spectrogram (Reaper, Raven and Amadeus Pro (Mac only). For further information on identifying species see links below.
The BTO, Sound Approach and Sovon have teamed up to produce a Protocol for Standardised Nocturnal Flight Call Monitoring (available here), and in parallel, significant improvements have been made to Trektellen for the submission and sharing of nocmig data.
Below are some links to help you get started: