Where do the sea turtles go? A novel system to track sea turtles

by Hariprasath R

Technological advances in animal tracking systems have enabled us to study animal movement to gain insights into their spatial use and habitat preferences. Telemetry studies have been used for spatial planning and conservation and management of different  animals. Traditional animal tracking systems use a variety of techniques ranging from UHF/VHF radio frequencies (Radio collars) to transmitters which communicate with satellites. Dakshin Foundation has now partnered with a local tech start up, Arcturus Inc, to support the design of a cost-effective telemetry device employing Long Range (LoRa) radio waves.

Transmitters typically record information on the animals’ location along with other environmental features including temperature, elevation/depth, travel speed, mortality etc. The costs of these are largely dependent on their range and sophistication of the technology used with radio transmitters being the cheapest and satellite transmitters being the most expensive. The other challenge with the instruments is regarding the ease of use where radio transmitters require active tracking to receive the locations of the animals while satellite transmitters can transmit their locations to their respective satellites which can then be communicated to the researchers at their computers.

Once the LoRa tags are developed and tested, they can be mounted on turtles. This information is stored in the tag and when the turtle surfaces again in the vicinity of a receiver stationed in a fixed location or a hand-held receiver, the data is transmitted through long range radio waves to the station or receiver. The data can then be manually downloaded at regular intervals. Six GPS loggers initially developed with funds from the Ruffords Foundation, functioned well in accurately locking geo locations and time stamps. The tags are now going to be tested in the field under various scenarios to test for water resistance, pressure and range.

The GPS-LoRa tags are the brainchild of Abhijit Kumar Nageshkumar, the proprietor of Arcturus Inc and thanks to his efforts we may be able to successfully deploy the devices on green turtles in Lakshadweep to better understand their movement ecology. This project can potentially fill gaps in our knowledge about their migration and foraging decisions which will be vital to management planning and to satisfying our curiosity about this charming marine dweller. We will also make these animal tracking systems accessible for a wider group of researchers interested in studying animal movement.

We would like to thank Abhijit Kumar Nageshkumar for the images.