Help SGLT Track Tamarins


How can I help Track-A-Tamarin?

You can help us save golden lion tamarins by donating funds towards the purchase of necessary radio telemetry equipment. It costs $10,000 a year to support our scientists in Brazil as they monitor tamarins in their forest habitat. If we are able to raise $9,000 per year, Holohil Systems, the company that manufactures the GLT radio collars, will donate $1,000 to reach our goal of $10,000!

What is radio telemetry? 

Radio telemetry is a technology that allows Associação Mico-Leão-Dourado (AMLD) biologists to locate tamarins anywhere in their forest homes. A radio telemetry system includes a very small radio transmitter attached to a special lightweight collar that does not inhibit normal activities of the GLTs as they scamper among the trees. AMLD biologists attach these collars to 1-2 adult tamarins in each of 15 monitored groups.  Each GLT transmitter sends “beeps” at a unique frequency that can’t be heard by tamarins or humans.  AMLD biologists then can use a radio receiver tuned to that frequency and a directional antenna to locate the group safely and quickly. Once the group of GLTs has been located AMLD biologists can follow it all day, recording its location using a hand-held GPS unit (global positioning system).


Why does AMLD use radio telemetry to track GLTs?

Although GLTs are small monkeys, each family lives in a large area of forest.  Each group of 5-10 GLTs occupies about 55 hectares (124 acres) of forest, an area greater than 55 city blocks! Without the help of telemetry, finding a small monkey in very dense tropical forest is nearly impossible.  AMLD has been using radio telemetry for 30 years to manage and monitor GLTs.  Telemetry is essential for AMLD to accomplish the following activities that are parts of AMLD’s plan to save the species from extinction:

  • Monitor the health and size of the wild tamarin population

AMLD’s biologists use the radio telemetry receiver and directional antenna to locate the 15 GLT groups that they monitor wherever they are in their forest habitat throughout the entire range of the species. Once they have located one of these GLT groups, AMLD biologists note the identities of individuals in the group, including births and deaths, and the size of the group’s home range.  This monitoring of these 15 groups is AMLD’s “finger on the pulse”  of the entire wild GLT population.

  • Detect threats to golden lion tamarins and their forest

Using radio telemetry, AMLD biologists follow monitored GLT groups throughout their home ranges.  Threats such as signs of hunters, trappers, fire, or deforestation are reported promptly to the Brazilian authorities.

  • Manage the wild tamarin population

Because some GLT groups are located in forest fragments too small to support them, it’s occasionally necessary to move (translocate) individuals or groups to a new location.  Radio telemetry allows AMLD biologists to follow these translocated tamarins, record their progress in their new forest, and rescue them if necessary.  Radio telemetry also is key to learning how to improve AMLD’s management techniques.

  • Ecotourism that provides forest-friendly income for local landowners

Working with local landowners, AMLD offers the opportunity for tourists to see golden lion tamarins in privately owned forest.  Radio telemetry allows AMLD to quickly and safely find and follow the tamarin  groups for the tourists to observe and photograph.

How much does this equipment cost?

AMLD uses about 55 radio collars each year.  As GLTs are quite small, the transmitter collars must be small and light, and therefore their batteries last only about 6 months. A new radio collar costs $300, including international shipping and customs charges. Rebuilding a used radio collar and replacing its battery costs about  $170.  A new radio telemetry receiver costs $750, and a new GPS unit is $450.  AMLD needs a new GPS unit and radio receiver every 2-3 years. The telemetry team also spends funds on gas for travel around the area. Overall, AMLD spends about $10,000 on telemetry equipment each year.


A GLT radio collar (from Holohil System Ltd.), GPS unit, and radio telemetry receiver.

How can I help track a tamarin?

You can help AMLD save golden lion tamarins by donating funds towards the purchase of a directional antenna ($125), one or more new radio collars ($300 each), a GPS unit ($450), or a radio telemetry receiver ($750), or donating any amount that will be used for related funds such as gasoline or supporting the salary of one of our team members in the field. If SGLT is able to raise $9,000 per year Holohil Systems, the company that manufactures the GLT radio collars, will donate $1,000 to reach our goal of $10,000!

To thank you for your donation, SGLT will send you a certificate acknowledging your support. To thank you for a $125 donation, SGLT will give you a “shout out” on our Facebook page and a certificate. In thanks for a $300 donation, SGLT will send you a certificate acknowledging your contribution and a photograph of a wild GLT wearing a radio collar like the one you provided.  If you donate $450, SGLT will send you the above plus AMLD’s most recent report from the field.  As a reward for a $750 donation we will also arrange for you to speak (via Skype) with an AMLD or SGLT biologist with decades of experience working to conserve GLTs. If you donate $1,000 or more you will also have the opportunity to name a baby tamarin born to one of the monitored GLT groups.  Donations are deductible on United States income tax.

Need ideas on how to help Track-A-Tamarin by holding a fundraiser? Check out our Track-A-Tamarin Testimonial page!

To donate, simply click here.  

If you wish your donation to be a gift for someone, email us at with the recipent’s information.