to recognize marked bats using a hand-transponder reader and also to recognize bats when they
crawl through the automated balances that I have installed in Gamboa.
"How does one track the comings and goings of bats, birds, frogs and other animals?
A rice-grain sized PIT tag injected under the skin makes it possible to identify individuals
using a hand-held tag reader.
Passive Integrated Transponder tags consist of a small glass capsule containing electromagnetic coils that
act as a combined receiver/transmitter. When triggered by an interrogating signal,
the antenna in the tag uses voltage generated by the signal
to radiate an alternating magnetic field coded with a unique ID number.
This technology was first developed in the 1940’s to distinguish friendly from enemy aircraft.
The same concept lets you open a door by waving a card in front of a reader.
Since the 1980’s PIT tags have been employed to monitor fish populations and to identify
valuable zoo animals and pets. Radio Frequency Identification Technology in printed tags
tracks goods in the global supply chain. Seven millimeter-long PIT tags cost a little less than $5.00 each."