What is involved with Tapir Radio Collaring?

We have 12 tapirs radio collared around Sirena Biological Station, Costa Rica. To follow the tapirs we use a telemetry system that sends a signal from the collar to the hand-held receiver. The receiver beeps louder the closer we are to the collared tapir. However this does not tell us exactly where the tapir is--only the general area. To find out where the tapir actually is we have to use a little geometry.

Figure 1: Telemetry unit used with radio collars

For each tapir location we get two compass bearings. These bearings are used with telemetry software to triangulate the actual position of the tapir. This is done for each tapir 6 times a month. So we get a total of 144 readings a month; or 72 locations a month for each of the twelve tapirs.

These collars have to be very heavy duty. Each day the tapir will submerge the collars (and themselves) in thick mud and water, so collars (and tapirs) have to be waterproof. The collars chosen for this project have worked well for the pasti 12 years. There have been no recorded effects of these collars having a negative effect on the tapir social behavior. There is no decreased reproductive rate or mate avoidance from these collars. Tapirs don't seem to care that they are on.

Figure 2: Charles Foerster darting tapir with CO2 gun

Figure 3: Tapir getting relaxed after being darted.

The work does not stop here! We have to maintain the collars. Each collar will last about 2.5 to 3 years. So every 2 to 3 years we have to anesthetize each tapir. This is no small job. We have to locate the tapir and then mix a special tapir cocktail of anesthetics. This mixture has proven to work very well with the tapirs. The tapir is darted (Fig. 2 and 3).

Figure 4: Getting tapir teeth molds on anesthetized tapir.

After the tapir has received the dose they get sleepy. They gently lay themselves on the ground and we place ear plugs and blindfold to keep the animal comfortable and minimize any disturbance to them (Fig. 4). We try to obtain as many samples as we can from each tapir knock down to get the most out of each procedure. We collect: ticks, small piece of skin (for genetics), teeth molds, and body measurements. After all samples are collected we inject the tapir with a drug reversal so that the drugs stop working. The tapir wakes up and we can continue to track the tapir using the telemetry unit.