Sounds of Spring

Looks like it is shaping up to be a cool and somewhat damp weekend for our nature challenge this year. With predicted temperatures cooler than 10 degrees Celsius, the likelihood of seeing flying insects is low. On the plus side, I expect to be finding a lot less ticks - Yay!

Spring migration is always interesting to observe and there is no shortage of wet spots for waterfowl to pause here before attempting to go further north. Early nesters like crows and peregrine falcons are already involved in setting up their territories and improving their nesting sites. Recording a few calls to add to your crow photos will help identifiers feel more certain about proposing an id.

If you have never tried adding a sound observation, this is an ideal time of year to start. Many species assert their presence to their fellows with distinctive noises often at pretty high volume to attract mates and defend territory. They tend to stay in one spot and make the noise over and over again - which gives you time to get organized.

The simplest method from a technical viewpoint is to use the iNaturalist phone app. Choose 'Observe' and then 'record sound' and you are on your way. The hard part is no edit. Its pretty good if the target sound is pretty loud, pretty predictable and you can get the rest of the world to be be quiet - or at least quieter than the sound you are trying to capture. I suggest Canada Geese for your first attempts - particularly that situation where there are a pair on the grass and the male is yelling repeatedly at top volume at 1 minute intervals.

For less of an adrenalin filled experience, you can record longer captures of sound and then later back in the comfort of your interior space, edit out the bits that you want to use for observation. You can use your phone or camera's video recording capability, or get an inexpensive handheld microphone. Outdoor recordings generally benefit from the addition of a fluffy fake fur cover over the mike to help reduce wind noise. Lots of DIY help out there for those. I generally make sure I take a photo at the same time as I record a sound observation - even it is not of the thing I am listening to. That way I will have the geo-tag from the photo to use for the location of the sound observation. I don't generally record more than a few minutes at a time as it makes the files easier to deal with later.

Once you have your recording on your computer, you can use Audacity, a free, open source, cross-platform audio software to pick out the pieces that you like. Its a bit of a learning curve, but you don't need to know how to use all its features to be successful and the documentation is pretty helpful.

My general process boils down to the following.

1. Open the sound file in Audacity.
2. Switch from waveform view to spectrogram view - this makes it easier to see the individual sound sequences made by the different organisms
3. Press play and listen to the whole thing making notes of where the 'good' bits are
4. Use the selection tool to isolate a 'good bit' and play just the selected section.
5. export the selected section as a WAV file
6. upload it as an observation
7. after it is uploaded listen to it on the inaturalist website. If I cannot hear the sound from the uploaded file - I delete the observation.

Here's an article with instructions for using Audacity to add audio to observations on eBird that you might also find helpful. Note that iNaturalist does not follow the eBird conventions for the initial 3 second buffer or the use of voice announcements. It does show you how to normalize your file which may reduce the number of times you use my step 7. :)

Today we have audio recordings of 195 different species in Manitoba. Looking forward to hearing what is found next.

Have fun experimenting!

Research grade observations with sound recordings from Manitoba

Publicado el 23 de abril de 2022 a las 01:11 PM por marykrieger