How are seals tracked?Updated 5 months ago

Elephant seals are tracked in a couple different ways. First, a select few seals each year are equipped with flipper tags with a unique alphanumeric ID that allows researchers to find them on the beach each year and record their age, whether they are raising a pup, and which other seals they are interacting with. 

Seals are also often given a hair dye mark on their fur to help researchers more easily identify individual seals in a large group. To track where seals go and measure other variables in the ocean, scientists carefully sedate and equip seals with location trackers that either transmit data in real time to a satellite when the seal is at the surface, or store the data onboard the device for scientists to recover from the seal when it returns to the beach to breed or molt in between foraging migrations. The trackers are affixed to the seal’s fur with a quick-setting marine glue. After the tags are recovered, the seals naturally shed the remaining glue through a process called a catastrophic molt, during which they shed all their fur and outer layer of skin at once.