Radio Transmitters on Purple Martins

Last Sunday I got to help with a project to try to determine where Purple Martins move to after they leave their breeding colonies. Researcher Kelly Applegate came down to the colony Mark and I band every year in order to put radio transmitters on 3 birds that will be followed using a mobile receiver.


This is an after second year male that has a transmitter on it's back. This bird will be tracked for the next 3 months or so.

Putting Radio Transmitters on Purple Martins from Roger Everhart on Vimeo.

This is a short video showing the process of catching and placing radios on the PUMAs.


The transmitters are quite small as can be seen by comparing it to the toothpick above it on the table. The antenna will trail off the back of the bird between it's tail feathers and should be able to be spotted when the bird is in flight.


The transmitters are attached by first gluing a small piece of cloth to the feathers on the back of the martin and then gluing the transmitter to the piece of cloth.


The glue is a fast acting contact cement so the placement of the radio has to be accurate the first time.


The glue takes about 4-5 minutes to dry so the birds are held until they can be released.


Once the glue is dry the bird is ready to be released. This after second year male was one of the 3 birds processed that day. We also put radios on an after second year female and a second year female.


Orlin S. gets to release the birds from his colony. You can't see the bird but notice the shadow on the ground. All the birds flew well and resumed feeding almost immediately after their release. The white spot on their back where the transmitter is located is easily seen from quite a distance.


Once the birds were released, Kelly entered the radio frequencies from each transmitter into his receiver and began to locate and follow the birds as they flew around the colony site. By the end of this month the birds at this colony will have moved on and then it will be a question of trying to locate them as they gather in large flocks before they head to South America this fall.