Last week, from the Yasny launch base in eastern Russia, a rocket soared into space carrying several dozen satellites, many of them dedicated to scientific endeavors. An instrument designed to track massive dust storms, for example, represents Iraq’s first spacecraft. But another of the modest-sized orbiters, dubbed cube satellites, marks an important step toward an orbiting system dedicated to tracking large-scale movements of animals small enough to hold in an adult hand. “For this satellite, it’s a lot about solving the mysteries of migrations,” says zoologist Kasper Thorup of the University of Copenhagen, who is in charge of the wildlife tracker and attended the Russian launch.
Funded by the Technical University of Denmark (DTU) and the Center for Macroecology, Evolution and Climate at the University of Copenhagen, the instrument, called DTUsat, will record data from 4.6-gram tags that researchers plan to place on animals such as the common cuckoo, a parasitic bird that lays its eggs in another species’s nest. Affixed among the cuckoo’s feathers, each tiny tag will relay the bird’s position to the satellite circling thousands of meters above. DTUsat will then collect the tag’s information and pass it on to a base station at DTU. Two of the tags have already been made, and the researchers hope to soon test whether they can connect to the now orbiting DTUsat.
Though an independent mission, DTUsat is a forerunner for the ICARUS (International Cooperation for Animal Research Using Space) project, an ambitious plan to equip birds and other small mammals with tags that transmit their location directly to the International Space Station, rather than via a satellite relay. The ICARUS project reflects growing interest in how small animal migration patterns are influenced by global issues such as climate change. Thorup and Martin Wikelski of the Max Planck Institute for Ornithology in Radolfzell, Germany, the lead researcher for ICARUS, hope that the DTUsat’s launch provides incentive to build location-transmitting tags that have the power to send signals to the ISS. The researchers speculate that the tags will be ready by the end of 2015. Now, the tags are still in the developmental stage and are about 5 grams, but Thorup and Wikelski hope that the tags will weigh as little as 1 gram in the future.
The ICARUS team hasn’t finalized a list of animals they want to tag, but cuckoos could near the top of its list. The parents of the parasitic species abandon their eggs in the nest of other species, yet cuckoo chicks somehow know to migrate from Europe to Africa. “It’s a crazy behavior that we don’t really understand,” says Margaret Crofoot, a member of the ICARUS team. “How do they know where to go? This is a bird that is too small to track using existing tags.”
For ICARUS, each tag would be solar rechargeable. For the sake of efficiency, the tags would collect data constantly but only send it to the ISS when the space station passes overhead. Both of these tactics can help prolong battery life as the tags become smaller, eliminating the need for heavier batteries with longer lives.
But even as the tags shrink, the ICARUS team plans to tag animals large and small in the interest of conservation. One of the project’s long-term goals is to attach tags to reintroduced or relocated Bornean orangutans displaced by deforestation. “We don’t know where these animals go, we don’t know what their fate is,” Crofoot says.
However, DTUsat and ICARUS still have a long way to go before they can help researchers pursue any large-scale problems. DTUsat will track only six tags simultaneously, whereas ICARUS may track thousands. For ICARUS, the team will have to attach a large antenna to the ISS to compensate for the transmitters’ small size. With funding from the German, Russian, and European space agencies, they plan to mount such an antenna in 2015.
In the meantime, Thorup is hopeful the DTUsat will help answer questions about the cuckoo’s oddball lifestyle. Does the cuckoo have a particular habitat that it must live in? he wonders. Will the cuckoo find a different habitat when global climate change inevitably affects its home? Soon the answers may be streaming into space and back to Earth.