Spectrogram of Fox Vulpes vulpes

Nocmig Top Tips

It is great to see so many people taking up nocmig recording at the moment. It might seem like getting the equipment sorted is the battle won but there are still some steps that will make your nocmig experience more productive and enjoyable. These ‘top tips’ were compiled in conjunction with David Darrell-Lambert (@birdbrainuk) and James Lidster (@james_lidster), experienced nocmig recorder from London and the Netherlands.

1. Identifying out of context invisible birds is tricky and there’s no shame in not knowing a particular call. Everyone, new and experienced alike gets calls they can’t place but there’s a great community of people keen and willing to help.

2. Take some time to learn the ambient sounds of your local environment. There will be hundreds of clicks and squeaks, not to mention dogs, foxes (see below), cats and other critters (and humans) that will try to fool you. Once you learn the visual signs you can process recordings without listening to every one.

3. Start off focusing on clear, close sounds. Faint sounds are often impossible to identify, even by experienced nocmig recorders.

4. Indistinct notes from the Robin two streets over will sound like almost any rare bird you can image. Get used to what different night singers sound like. Look for regularly spaced song phrases. Also, song from stationary birds often look fuzzy on spectrograms due to slightly delayed echoes off buildings, whereas flight calls are usually crisper, even if they’re quieter.

5. Get Audacity configured in nocmig mode so you can produce clear spectrograms to identify species and share with others.

6. Always include both time and frequency axes when sharing spectrogram images. When sharing sound clips, don’t crop them too tight. Include 2–3 seconds before and after the call so ears can get accustomed to the volume before the main event.

7. Familiarise yourself with the range of calls of the common nocturnally active species. Tawny Owls produce a wide array of calls (see here). In the UK the following account for over 75% of all nocmig calls logged on Trektellen during 2016–19:

  • Redwing (61,000 calls logged on Trektellen)
  • Song Thrush (14,000 calls)
  • Blackbird (5000 calls)
  • Coot (2000 calls – the Great Tit of the night, making lots of different calls)
  • Moorhen (5000 calls)
  • Water Rail (380 calls – scarce but variable and confusing)
  • Little Grebe (380 calls – beware of this Whimbrel impersonator)
  • Grey Heron (1800 calls)
  • Wigeon (2000 calls)
  • Oystercatcher (1500 calls)

8. If the spectrogram looks like a Redwing but doesn’t sound like one, it’s probably a Redwing. If it sounds like a Redwing but the spectrogram doesn’t look like one, it’s probably also a Redwing! They vary massively, see here for examples.

9. Do you have an odd sound that is clearly a flying bird? Then check out the range in Coot calls as well.

10. You may pick up wing beats. It is usually not possible to identify these without calls.

11. Register on xeno-canto and upload mystery recordings to get feedback and suggestions.

12. Log interesting records on BirdTrack and when you’ve really gotten hooked, consider submitting structured counts via Trektellen.