All satellite transmitters will eventually stop transmitting, however this does not necessarily mean that any harm has come to the turtle. There are several reasons why satellite transmitters stop transmitting. Some of these are:

1.    Attachment failure
Sea turtles love to hide in coral crevices and under rocky ledges where transmitters can get stuck and be ripped off. Some sea turtles scratch their carapace to get rid of barnacles and may scratch off the transmitter. Transmitters do not float so once lost in the ocean it will stop transmitting.

2.    Antenna failure
Antennas can get damaged by turtles hiding under ledges or scratching their backs. This is probably the most common cause for transmitters to stop transmitting.

3.    Saltwater switch failure
Satellite transmitters are equipped with a switch that conserves battery life by turning the tranmitter off when the turtle is below the water’s surface. However marine organisms like algae, barnacles and corals can inhibit the function of the switch and therefore stop transmissions.

4.    Dead battery
Battery life is usually at least a year, however, battery life depends on how often the turtle surfaces (as described above) and can be highly variable.

5.    Turtle mortality
Sea turtles face many threats and a proportion of tracked turtles will end up getting caught in fishing nets. If the turtles are kept on the boat for consumption or other purposes, this will show as a linear movement towards a harbour. Sea turtles also face the danger of ghost nets and other marine debris floating in the ocean and they can get entangled or eat debris and die.