One of the first pioneering applications of RFID technology was not to track goods passing through a supply chain but rather to track living beings moving through an ecosystem.
The Bonneville Power Administration (BPA), a federally-owned not-for-profit public utility headquartered in Portland, Oregon, has been using RFID since 1986 to track salmon migration patterns through the Columbia River basin’s vast and complex network of 400 hydropower dams and waterways.
The technology is used to bring scientific rigour and accuracy to the study of declining salmon stocks in the Pacific Northwest – and to help bring some social harmony to the region.
Salmon play a major role in the economy, history and lore of the region, and emotions run high as stocks continue their hundred-year decline. The BPA is at the center of a vortex of competing interests: environmentalists, fishermen, and 13 native tribes. Geographic disputes are also in the mix – the Columbia River’s headwaters begin in the Canadian Rockies of British Columbia, and the river snakes its way south through five U.S. states, feeding a system of tributaries and lakes on its way to the Pacific Ocean.
Many groups blame the system of hydropower dams for the loss of their salmon, claiming they prevent the fish from making their way through. “For ocean-going salmon to return and thrive we must have safe fish passages that will help salmon avoid being chopped, whipped or liquefied in power turbines at each dam or knocked senseless in the turbulent backwater below the dams,” is the vivid statement on the Canadian Aquatic Resources section of the American Fisheries Society’s Web site.
Some large and fishy loss numbers were bandied about by advocacy groups in the 1970s, claiming a sharp and sudden drop in salmon. No headcount was taken of the salmon passing through the river system before the dams were originally built, so such numbers were based on conjecture, not science. In addition, native tribes are entitled by treaty to half of the salmon catch in their sectors – but half of what number?
To further complicate matters, about 14 different sub-species of salmon were classified as endangered, and the BPA was mandated with their preservation. But environmentalists claim the salmon hatcheries introduced by the BPA to restock salmon displaced by the dams contribute to loss of species diversity, as the wild salmon inter-breed with the raised salmon released into waterways.
RFID technology was introduced to obtain some much-needed metrics to help track and tackle all these issues. “We’re more “public” than a public utility – our mission is to restore fish and wildlife in the basin, and [to that end], our profits are ploughed back into the system,” said Scott Bettin, a freshwater fisheries biologist with the BPA. “We spend $600 million annually to recover fish in the Columbia basin, and it’s important that we figure out where our greatest losses are.”
The BPA started tagging salmon with RFID chips during the 1980s, working with RFID vendor Digital Angel based in St. Paul, Minn. to develop a massive tracking system. “We helped develop the RFID technology with Digital Angel,” said Bettin. “Tag development came from our funding, and we did a lot of R&D to make them work. The tags were big initially, and we’ve shrunk them down to the size of a grain of rice now.”
About two million salmon have been tagged every year by the BPA’s corps of biologists and engineers since the system was introduced. The tiny, passive RFID tags can upload up to 64 bits of information when they are activated by salmon swimming past readers. The tracking system allows up to 16 billion combinations, so each tag is essentially a unique identifier, with its own frequency, explains Bettin. This allows biologists to collect highly detailed information: sub-species, age, waterway and habitat of origin, condition of the fish, and so on. Storing the data and crunching the numbers requires a powerful computer system with almost the horsepower equivalent to a Cray supercomputer, said Bettin.
The BPA also worked with Digital Angel to build a complex system of RFID scanners into the pipes and flumes used to provide the salmon safe passage across dams and sluiceways, said Kevin McGrath, CEO of Digital Angel. Recently, the company began developing a series of 16×16-foot antennas that read RFID tags in juvenile salmon as they pass through large chutes at nearly 60 miles per hour.
By pinpointing dangerous areas that needed modification to help the salmon survive, mortality has been reduced by about 15 to 20 per cent, said Bettin.
BPA scientists have assembled a rich, detailed repository containing information about all facets of a salmon’s life cycle and migration patterns, which will help them better manage dam operations to minimize the impact on fish and wildlife. More recently, researchers have been using the RFID tags to determine how shoreline development affects salmon, what happens to them out at sea, and if birds eat them in quantity. “[A lot of] the tags were ending up on two main islands,” said Bettin. “Caspian terns eat the tagged salmon and then [excrete] them onto their nests. These islands glisten with RFID tags.”
