In order to study the adaptation of the specimens and to evaluate the viability of the releases a method must be used to effectively know if the animal has survived a reasonable time after releasing.

In order to obtain information about the birds released after their release, or what is the same, to follow up, there are several systems (visual marks, colored rings …).

Radiotracking is the ideal method. An emitter is placed on the released animal. The task is to follow the signals from the receiver. This method provides a large amount of information on the marked individual upon release and is the only possible option to seriously evaluate the efficacy of releases in nocturnal birds, since it is the only method to obtain post-release information in birds that they are not visually detectable. The advantage of this system is the high degree of monitoring that can be performed on the behavior of the marked animal.

The emitters can be of innumerable types and characteristics (duration, weight, frequency …) being basically placed in the tail or the back of the bird. The receiver allows us to receive the signal coming from the transmitter and locate the bird.

All birds released carry an official metal ring, and only a small part is provided with radio transmitters.

All birds released carry an official metal ring, and only a small part of the radio.

IF YOU FIND A BIRD THAT HOLDS A RING, CONTACT THE OFFICE OF MIGRATORY SPECIES
(Ministry of the Environment)
Gran Vía de San Francisco, 5
28005 Madrid
Email: oem@mma.es
Tel. 91 596 49 84