BattyBirdNet-Pi

Its 7 or 8 years since I last did any bat monitoring.

 

To be honest, I got a bit bored with it.

But now I've set up a BattyBirdNet-Pi system ...I'm back!

BatGuru: a British bat ID helper

My BatGuru is a program written in Gambas which helps me identify British bat species based upon echolocation call data.

It simply saves me having to juggle the key parameters in my head as I scan the charts in my reference book.

But identifying bats from their calls is tricky due to the wide variability of their calls.

Common Pipistrelle Feeding Buzz

Bat echolocation is all about catching a meal.

After all, if bats could safely feed during the day, they wouldn't bother to stumble around in the dark of night. 

So its good to catch the occasional ultrasonic recording of bats catching their prey.

Bat Call Logger: full-spectrum analysis

With the recent step change in the weather, I was able to run the system last night and capture bat calls for the first time this year.

It looks like my modifications to the system are paying off.

I'm now getting full-spectrum (ultrasonic) recordings which are much easier to analyse than the previously used Frequency Division recordings.

Bat Call Logger: implementing pre-capture

My bat call logger uses a very simple/crude means to trigger recording.

This seems to work, but a few recordings are blank, as if the triggering signal has stopped before the recorder kicked in.

By having a pre-capture function, I should be able to capture a sequence before the trigger takes affect.

Bat Call Logger: recording ultrasound

My bat project has been on the back-burner for the last few months, as I understand that bats don't venture out much during the winter.

However, the Weather Man on BBC's Winterwatch did say he had seen them flying around on a few mild evenings during January!

So maybe its time to do a bit more work on my Bat Call Logger and check if there are any out there.

Bat Call Analysis: second thoughts

I'm still trying to reconcile my bat call recordings with the data provided in the Jon Russ book "British Bat Calls".

This caused me to question whether my home-brew bat detector was a reliable witness.

Just how much faith can I have that my FD detector is producing sensible recordings?

Bat Call Analysis: more difficult than it looks!

So I've now got a few hundred recordings from my Bat Logger, collected over a number of nights.

Time to settle down with Audacity and a pint of IPA, and analyse a bunch of waveforms.

Identifying the bat in question is easy, right? Its just a matter of determining frequency, repetition rate...