Ooophaga pumilio 2019 © Alex Villegas
What is CROAC?
If you are out walking you often can hear frogs before you see them, if you see them at all! Each species of frog sounds different - some croak, some chirp, some even bark. Some sound like insects and others like birds! Just like people learn bird calls you can use this app to help you learn frog calls either for personal fun so that you can identify them or so that you can help with amphibian surveys.


This app gives you useful information to help identify and learn 10 tropical frogs and their calls. There are genuine wild frog calls on the app that you can play back to learn their calls along with information on each frog species. The species on the app are ones you might see on the trails of La Selva Biological Station (Costa Rica), in other areas of Costa Rica and in many other parts of Central America.

You can also record frog calls using the microphone on your phone and create your own call library on your phone.

CROAC can also help you identify the frogs you can hear by analysing and identify the frog calls for you by only using your phone! It will give you some suggestions as to what the species might be in your recording.



No data connection is needed once the app is downloaded. All this analysis is done on your phone, so unlike many other frog call ID programmes you don’t need to download your recordings to a PC and then use complicated software to analyse it. Obviously you can still download your recordings if you want to do this.



However, when many frogs call at once in a "chorus" this obviously makes call analysis very difficult and the same if the calls are very quiet. So the app is best used when only one or just a few species are calling and they are calling loudly!



If you want to you'd like to share with the world your frog call recordings you can contact us through the email at the bottom of the page. We are always happy to get more sounds in the library and map locations for our site.

Who are we?

This is a University of Manchester citizen science project. The app was developed by Richard Bamford (Advisory LTD). Richard wrote all the software and also designed the app and website for the project. The project was led by Andrew Grey (Manchester Museum, University of Manchester), Professor Amanda Bamford (School of Biological Sciences, University of Manchester) and Alex Villegas (Swarovski Optik, Costa Rica). Alex kindly provided 9 of the beautiful photos and most importantly he provided all the frog calls which he recorded in the wild in Costa Rica. Matt O’Donnell provided the photo of S. baudinii and proof read the text.

How you can help!

  • Please download this app (from Google Play) onto your android phone and use it to enjoy listening and learning about 10 tropical frogs.

  • If you are lucky enough to be in Central America, where these frog can be found, go out and enjoy the wonderful world of frogs, using the app to help you identify them and record their calls.

  • If you want to share your recordings with us and where they were recorded please contact us below. This can help scientist map and track where these frogs are living and also provide an invaluable record of their calls.

  • Share the app with your friends!

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