ElephantAcoustics

Machine Learning Model forElephant Communication Monitoring:

1. Introduction

Elephant – the largest land mammal as commonly referred is also a sophisticated communicator. With rumbles to roar, trumpet to barks and snorts, they communicate and socialize with their family in a variety of ways. This ability is quint essential for their survival in the wild.

2. Call Types

Elephant Biologists and explorers have recorded thousands of elephant calls. They have divided these into different categories, or “call types” (e.g., rumbles, trumpets, roar) based on behavioral context, call tone, and measurement, they have interpreted the meanings of the many intricate differences within each type.

Rumble is constitute to 80-90% of call-types and trumpet is another commonly used type. We have tried to classify these two sounds with ML using the Edge Impulse Studio. The project has 2 classes – rumble and trumpet to start and further call types can be added in future. The audio captured using the microphone can be classified in real-time and sent to the digital twin for studying the individual and herd behavior during various scenarios.

The elephant sound data were collected from various resources

https://www.elephantvoices.org/multimedia-resources/introduction.html

https://www.youtube.com

All sounds were converted to high-quality 48KHz sampling frequency file (WAV) and feed into the Edge Impulse Studio.

3. Classification Approach.

The classification blocks chosen are as below for two call types rumble and trumpet.

Rumbling is created by the larynx and is the regular form of communication with fellow elephants. Most elephant sounds are actually rumbles.

• These low-frequency sounds can travel over long distances and are used for everyday communication, helping the elephants communicate with other elephants that are far away.
• Calf make a begging rumble, Baroo rumbles send a message that the elephant is upset or uncomfortable.
• When males are searching for a mate they emit a pulsating musth rumble. Females respond with their own estrous rumbles
• Also, there greeting, bonding, Lets go rumbles and to persuade the herd to do something.
• In the wild you can sometimes hear many elephants rumbling at once, which means they are having a conversation and deciding what to do, or making a greeting with each other.

Trumpeting is created by pushing air through the trunk and is used when an elephant is highly stimulated.

• Trumpeting is the most famous and recognizable sound from an elephant’s vocabulary, its high-pitched tone heard for miles around.
• They emit it when they are stimulated. Sometimes it’s because they are excited and playful.
• It is also used when an elephant is lost, angry or surprised.
• Trumpeting is a way for elephants to warn others and get others to notice you. It’s usually a sharp, high-pitched sound that continues for a couple of seconds.

A quick validation using Live Classification gave some promising results.

4. Model Testing

We tested the inference engine with mix of datasets of rumble and trumpet samples and below are the performance.

The test accuracy is 88.09% as to the training accuracy of 99.4%, we still have some work on optimizing the model.

5. Further Work

The model can be extended for other major call types and /or sub-classify few call type such as greetings, let-go, baroo with rumbles.