Instead of waiting for the local people to arrive and scare the elephants away from their crop-raiding missions, possibly endangering themselves, and the elephants, this add-on device aims to automatically deter elephants! Making use of sounds that they associate with animals they dislike!

The two sounds which have previous experimental evidence for their efficacy in deterring elephants are: sounds of tigers and bees!

Wild Asian elephants distinguish aggressive tiger and leopard growls according to perceived danger http://rsbl.royalsocietypublishing.org/content/9/5/20130518

African elephants run from the sound of disturbed bees http://www.cell.com/current-biology/fulltext/S0960-9822(07)01718-6

Components

• HiFiBerry AMP+ (speakers: 25W, 4-8 Ohm; 12-18V 3A power supply) https://www.hifiberry.com/ampplus
• 2x 8 Ohm Magnetic Speaker 20W 100Hz ~ 10kHz Top Round, Square Frame 90dB http://www.digikey.co.uk/product-detail/en/cui-inc/GF1004H/GF1004H-ND/304448
• Raspberry Pi 3
• Power supply for HiFBerry AMP+
• Power supply for Raspberry Pi
• 3d-printed enclosure for device
• Box for battery
• XBee 2mW Wire Antenna - Series 2 (ZigBee Mesh)
• PowerBoost 500 Basic - 5V USB Boost @ 500mA from 1.8V+
• 6W 2V Solar Panel

This device will have a library of 200x10 minute duration audio clips (bees, tigers) to be selected pseudo-randomly (to prevent elephants becoming habituated to audio). The devices will be in range of the elephant-detection devices (for communication via RF using the XBee 2mW), and triggered by a simple yes/no message from the elephant-detection devices to begin their sequence of playing elephant-deterrent audio clips (bees or tigers).