To help with our understanding of what happens after release we track some of the wildlife using a radio transmitter or a satellite tag.
This allows us to follow the animals' progress in the wild and learn how, when and where to release animals to improve their chances of survival.
We tracked one seal using a satellite tag across the English Channel to Normandy, and learnt that he had lost none of his swimming abilities and was able to rejoin a colony of seals.
A life beyond
Beyond the first few weeks or months after release we use information collected by eagle-eyed people and organisations to build a picture of the lives of animals we have tagged and released long after they leave us.
By ringing gulls released from our centres we have been able to track them as far north as Spitzbergen, Norway and we know they have even reached the west coast of Africa!
If you would like to know more, take a look at our current research.