A female African Penguin with a green tag on its left flipperWIKIMEDIA, BROKENSPHEREIn 1971, NASA and the Smithsonian Institution deployed the first ever satellite collar, using a female elk they named Monique in the Grand Tetons in Wyoming. They spent months testing the collar, bright red and over 10 kilograms, to make sure it could survive everything an elk would put its way. The collar was well-armored, expected to make it through a frozen river without problems. Within a week after collaring Monique, she was dead.
NASA dubbed it a coincidence, but it illustrates an important concern that plagues most field biologists: Are the methods we use to research our animal subjects harming them, or inadvertently altering the biological systems we study?
As with most sciences, the main limit to knowledge in ecology is an observational problem: Our inability to fly, swim in arctic waters, run 120 kilometers per hour or sit in one place for a century creates serious barriers to understanding. In place of superhuman powers, wildlife biologists have spent many years developing methods for observing the natural world without having to be in constant contact with our animal subjects.
By marking individuals, we can recapture them later to estimate a suite of important ecological characteristics, such as survival, ...
