Tag Archives: Birding Know How

Bird Song Listening Field Research Device … OwlSense & Chirpity

Year 12

First the conclusion, then the details … I love the combination of OwlSense (field research birdsong listening device and Chirpity (birdsong analysis software). If you are looking for a device you can leave in the forest (up to 700 hours!) which will record birdsongs, OwlSense is fantastic! However, this is NOT a home consumer device like Haikubox or BirdNET PUC. OwlSense requires you to transfer / load the captured sound files (wav files) into your favorite analytical software package, in my case Chirpity. Consumer devices have the bird analytics integrated into their systems, and assume you are connected to the internet and have a power source. In those circumstances, the consumer devices give you an almost instantaneously bird species ID. See the bottom of this post for links to reviews / evaluations I have conducted on BirdNET-Pi.

This obviously begs the question why do I like OwlSense so much? Quite frankly for its product market niche, it soars! I can place OwlSense deep in the forest where it is off the grid and it will run for 700 hours without a battery recharge. Annotated screenshots for both OwlSense and Chirpity are founded later in this review. Prices are very fair. OwlSense is about $120 when I am writing this review, and Chirpity is free (giving a donation to the developer is nice).

  • 700 hours of run time in the field is amazing
    • My field research BirdNET-Pi unit only runs for 32 hours and requires a USB timer and large power bank (60,000 mAh). In addition anyone using a BirdNET-Pi device needs to build and configure the small Raspberry-Pi device themselves. OwlSense is ready to deploy to the field once you receive your unit. There is no need to build a small computer as with BirdNET-Pi.
    • OwlSense uses only one smaller inexpensive rechargeable smaller battery
    • OwlSense allows one to swap out inexpensive SD cards and bring the sound files home for analysis. I just turn the device “off” and “on” while swapping out SD cards and do a re-synch with the OwlSense app (an easy, quick process). If you copy the sound files while out in the field and replace the original SD card, a re-synch will not be necessary as OwlSense settings are stored on the SD card.
  • OwlSense is very configurable. I set my OwlSense to listen from sunset to sunrise … and then for the first hour after sunup. In this manner, OwlSense listens all night for owls, and then captures the morning “dawn song” when most non nocturnal birds sing or call out.

I previously mentioned that I use Chirpity to analyze OwlSense sound files. Quite frankly using Chirpity surprised me. During my initial episodes of analyzing the wave files, I used Cornell’s BirdNet Sound Analyzer. I tried both of Cornell’s GitHub windows versions (Basic and Sierra). While I love the work performed by the Cornell School of Ornithology, I found their sound analytical software slow and kludgy. Documentation for the new user was almost non existent.

Almost by chance I discovered Chirpity … free birdsong sound analytical software developed by Matthew Kirkland. Given all of birdsong ID software tends to use the SAME EXACT Cornell AI based bird sound database model, BirdNet, I tried analyzing wave files with the different software analytical tools:

  • BirdNet Sound Analyzer works but as noted before it was kludgy and slow. Sound Analyzer NEVER ID’d my local Great Horned Owls.
  • When I analyzed the exact same exact sound file with Chirpity, it ID’d my owls and made saving that sound ID excerpt to an archive easy. Chirpity also made saving my software configurations easy. Finally the software runs MUCH faster than BirdNet Sound Analyzer.
  • Remember, just like BirdNet Sound Analyzer, Chirpity is free, but I recommend giving the developer a contribution.

Enough of my written recommendations, it’s time for photographs / screenshots with my comments of both OwlSense and Chirpity.

1. Here is a photograph of OwlSense deployed in the forest.

Before attaching OwlSense to a tree, configure your device using the OwlSense Apple or Android App (Bluetooth must be enabled on your phone). A unique code representing your device will appear in the app. The images that follow are screenshots I took while using the OwlSense app on my Android phone. Press or click upon any image to expand. I used red rectangles or arrows/lines to call out app important features.

2. This is the OwlSense app startup screen. It is showing the unique ID app for my listening device.

3. Pressing or clicking upon the unique device ID brings up the configuration screen. The screenshots were taken while scrolling further down the OwlSense configuration scree.

4. Next Screenshot …

5. Next Screenshots …

6. Final App Screenshots. Confirm Your Location & Synch!

Using OwlSense in the Field

Remember OwlSense will run for up to 700 hours in the field on one battery charge. You may wish to occasionally visit the device to collect sound files for analysis at home. However, unless you need a fresh battery, do NOT take the battery out of OwlSense. If you remove the battery, OwlSense will lose your previous configurations.

Using the small buttons inside your OwlSense, assuming you are NOT changing the battery and your OwlSense is already configured, in order to swap out SD cards perform these tasks in this exact order:

  1. Press the “on/off” switch to turn your OwlSense “off”. Assuming all your small LED lights turn off, remove your SD card and copy the files to bring home (or replace with a new card)
  2. Press the “on/off” switch to turn your OwlSense  back “on”. Your OwlSense will use your previously set and synched configuration file.
    • If your OwlSense is set to “continuous recording via your configuration”, the “recording LCD” should start flashing.
    • If your OwlSense records only at other times of the day, the “standbye LCD” should start flashing
  3. If you swap out cards rather than reinserting your original SD card back into OwlSense, you will need to do a re-synch using the app. Configurations are stored on the SD card. You may store your desired configurations / settings in the “default section” of the app. Thus, re-synching is a quick and easy process.

You may wish to watch this short YouTube video created by the OwlSense creator and company owner, Troy Gruetzmacher. The video demonstrates the app / recorder configuration process. (video link for blog email subscribers)

Before I move on to the Chirpity sound file analysis review part of this post, I want to comment how responsive Troy Gruetzmacher (OwlSense company owner) to my questions. I originally contacted him just like anyone else via his company website “contact us” link.

My final comment about OwlSense is I recommend purchasing one extra battery and SD memory card per unit. USE the batteries and SD cards recommended on the OwlSense website. The recommended battery and SD cards have been chosen because of how well they work when installed in OwlSense while deployed in the field. Troy Gruetzmacher created OwlSense through his work at the Owl Research Institute. While the name of the listening device has “owl” within the product name, it works perfectly if one only has a daytime songbird focus.

Analyzing OwlSense Files Using Chirpity 

My first comment about using Chirpity, it is for use on a Windows or Apple Computer. It is NOT software that you utilize via Android or iPhone apps. Your usage case scenario is bring sounds file back from your remote birdsong listening device(s) for analysis. As noted I am using this software to analyze sound files collected by OwlSense.

Open your sound files in Chirpity … If you have a large number of files, open them by selecting the folder and NOT the individual files. This helps Chirpity process a large number of files w/o freezing up.

Configure settings for Chirpity –  All these screenshots are from the settings drop down menu. Review the settings. Some of the settings I always set are:

  • Model: BirdNET (the other models tend to by specific to birds in the United Kingdom)
  • Confidence Minimum of 70%
  • List: Local birds
  • Location: Obtain GPS coordinates via Google Maps
  • Library Location: Set your desired sound file archive location

Analyze your open sound files in Chirpity

Save desired files to your Chirpity archive – Select any record to play that ID and sound excerpts. Right click upon any record to perform additional edits including “delete”. For instance, you may not want to save hundreds of Black-Capped Chickadee song ID’s whereas the sound file for a Northern Saw-whet Owl is pretty cool and you likely will want to save this file. This command will save all open records to the Chirpity archive.

 

Chirpity Demo (video made by the Chirpity software developer and company founder / owner, Matthew Kirkland)(video link for blog email subscribers)

This ends the review of the OwlSense Birdsong Field Research Device utilizing Chirpity for birdsong sound files. Towards the beginning of this post, I talked about BirdNET-Pi. I utilize BirdNET-Pi both as a “home birdsong listening device” with immediate bird species sound ID’s, and a a field research unit. However my field BirdNET-Pi’s only run for 32 hours before they run out of power. Here are some reviews / evaluation links on how I use BirdNET-Pi. My research units are NOT the same as my home consumer BirdNET-Pi’s. I have made some programming /hardware changes.

All of these links are to my utilization and reviews of BirdNET-Pi.

Birding Knowhow!

Year 12

Occasionally I feel it is necessary to post this content such that new subscribers to my blog … now in the thousands better understand the resources which may be found via 365 Days Of Birds (this website). Remember, this site is non commercial. You will never find a single pop-up advertisement, sponsored link or any other paid content. I am a failure as a “paid influencer”. LOL!

I just want folks to better understand and enjoy our feathered friends … whether it is a free PDF download of one of my owl children’s books to how one may build a BirdNET-Pi bird song listening device. The rest of this post is copied from my “Birding KnowHow” page (always found and linked via my menu system) and was current as of today’s date, November 3, 2025.

Birding Knowledge, Reviews, Evaluations and Services

Index of my Birding Reviews of Services / Products (alpha by subject)

Running BirdNET-Pi Off Grid … Very Remote

Year 12

I have immensely enjoyed using my BirdNET-Pi bird song listening devices. I have built one for my home, cabin, and several friends. These BirdNET-Pi’s are connected to both the internet and electrical grid, and upload their sound ID’s automatically to BirdWeather, which enables me (and anyone) to remotely monitor both resident and migrating birds:

My successes with a connected BirdNET-Pi led me to wonder if I could use the unit for research in the field. Although the small Raspberry-Pi computer/box does not have a hard drive, it does have running locally on its microsim card the Raspberry-Pi operating system, the BirdNET-Pi software AND the Cornell Birdnet birdsong database. Thus if I could solve power, date / time issues for the database, AND protect the small computer from the weather everything should work fine.

It took some time, effort, and mistakes, but the answer was YES! I now have a BirdNET-Pi which runs perfectly in the field as a research unit. I tend to run my BirdNET-Pi for four to six hours in any given 24 hour period. I then have the Raspberry-Pi automatically shut off and then turn on the next day (or night). In my case I tend to have the unit run at night during the early morning hours through the first hour after sunrise. In this manner my box captures and records both owls singing/hooting at night and then catches the morning songbird sing.

Here is a photograph of my BirdNET-Pi in its weather proof box. It is hooked up to a 60,000 mAp USB power bank via a USB power switch (24 hour cycle set to turn on and off after 4 or 6 hours of run time), and my USB microphone. I just place the entire box on the ground and hook the lavalier microphone to a tree branch. (This begs the question why don’t I use solar power? Answer: Solar is not only expensive, but needs to be deployed in an open area, which even in remote wilderness like northern Minnesota encourages theft)

Pi Power Adjustments

I actually turn off my Raspberry-Pi’s cooling fan (disconnect the pins given cold temperatures in Minnesota), wifi and Bluetooth. This helps conserve power for a remote unit running on a battery in the field. This configuration yields me about 36 hours of run time in the field.

Hardware Pi Modifications

Installing the RTC (real time clock) is simple. This chip, which has a battery and clock, allows your Raspberry-Pi 4b which has neither to always know the correct date and time. This data is then fed to your BirdNET-Pi installation such that every unique sound ID has date and time information for each database entry. There are some minor coding changes covered in the “software pi modifications” section of this post.

Gently push the RTC chip down onto the last / inner row of the computer pins closest to the end of the case. It is likely you will have to remove the pins for your cooling fan, and perhaps move the fan itself. Don’t worry, there are other 3.5 amp and electrical grounding pins for your fan (see this 4b pin mapping diagram).  Your hardware installation is complete.

If you are like me, the location of my cooling fan had to be moved to install the RTC chip. I screwed my fan onto the top cover of the case. It is still easy to connect the fan’s pins through the case’s provided openings. The fan’s case is actually quite sturdy, and your entire unit is protected within your weatherproof box.

Software Pi Modifications

Edit Addition on April 6, 2026: I have discovered that these instructions only work with the older version of the Raspberry-Pi Operating System (Bookworm, not Trixie). I had to rework a recent Pi installation which was running Trixie back to Bookworm. I found “fixes” for the Trixie “hwclock” issues, but could not make those code changes work for me. You may be more successful.

These are the coding and software instructions for installing the RTC chip. BirdNET-Pi normally gets its database time and dates via its network connection, but obviously a remote unit will not be connected to any network. Follow these steps:

  1. Via BirdNET-Pi settings, turn off “get time from network”
  2. Via Raspberry Pi turn off wifi (and Bluetooth)
  3. Shut down your Pi and remove top case cover
  4. Install the RTC chip (see hardware section directly above)
  5. Reboot your Raspberry Pi
  6. Create a terminal window session

Type the code found below. The command shown below brings up the file “boot config.txt” which will be edited by the Raspberry Pi “nano editor” (short Nano tutorial via YouTube)

  • sudo nano /boot/firmware/config.txt
  • At the bottom of the config file which is now open, add this code (a comment line):
    • # This is YOUR NAME’s RTC module code
  • on the next line type this code
    • dtoverlay=i2c-rtc,ds3231
  • Invoke the SAVE Command which is a <ctrl x>
  • Accept overwrite for config.txt

Reboot Raspberry Pi and type these 3 commands:

  • Create a terminal window session
  • Type this code: (note my comments within the parenthesis … “_” or underscores represent “spaces” within your code)
    • sudo_hwclock_-r (shows current time on computer)
    • sudo_hwclock_-w (writes todays time and date to computer)
    • sudo_hwclock_-r (shows current time on computer … did it change??)

If yes … everything is fine. Shut down your Raspberry Pi. Remember to put Pi and BirdNET-Pi back on network time if desired. You may now toggle between using your RTC chip or the network (if connected via wifi or ethernet) for the current time. You also may wish to check the Pi’s time and date again using the commands given above.