Originally we used Telenax models TXB 125G and TXB 124G radio transmitters. These were well made units but we are now using Holohil and ATS RI-2Btransmitters with our turtles.
Our receivers are currently ICOM IC-R10 scanner units. We have two units that are getting older and we hope to retire one of the units and upgrade to a new Wildlife Materials unit in 2010. We are using two different antenna models: a Telonics RA-14 H-type directional and an Arrow, Yagi type 3 element directional antenna. A transmitter (AVM), receiver (ICOM) and Arrow antenna can be seen in the photo below.
Below is a close up of a Transmitter and yes, that is a quarter next to the transmitter! Each transmitter brand has a different expected battery life: The Holohil units that we are now using have a field life expectancy of 2+ years.
How it works.
Upon finding a turtle and attaching the transmitter it will then be released at the exact site of capture as soon as possible.
The transmitter sends out a pulse which will be picked up by the hand-held receiver and antenna set. This will be translated into an audible "beep, beep, beep" sound from the receiver which increases in strength the closer the receiver is to the transmitter. By using the receiver to locate the transmitter, we will be able to locate the turtle.
Turtles will be located one to two times per week. Each time we find the turtle, we will record vital environmental data to help us determine its habitat usage and movement patterns. During each location day the turtle will usually not be touched or disturbed in order to reduce stress with the exception being that the turtle's weight and general condition will be recorded once per month (except for during the winter months). Photographs and short movies of the turtle and it's habitat will be taken if weather/conditions/time allows. These videos will be uploaded to the Earthshine Nature's Youtube channel.
The general location data will be plotted on a topographic map as a reference. Place names have been removed from the map and the turtle's locations on the map will be approximate for obvious safety reasons. Over time, each turtle's habitat usage will be revealed as well as its home range and possible interactions with other resident turtles and wildlife.
This study will generate valuable scientific information on Eastern Box Turtle natural movements and habitat usage in the western North Carolina mountains. This data will be made available to the BTC, NCWRC, NC Zoo and the North Carolina Non-game and Endangered Wildlife Program that is working to preserve animals like the Eastern Box Turtle whose numbers are declining across its range.
My hope is that this study will become a great hands-on wildlife study for all Earthshine visitors, guests and staff alike and will continue for many years to come.
NOTE: Please do not attempt to radio-track a turtle or other wild animal on your own. Radio telemetric wildlife study is a very specialized discipline. First and foremost is the safety and correct treatment of the animals being studied and secondly it takes years of study to learn the "how to" of the use of radio telemetry equipment and other data collection equipment.