RFID Tracks Salmon Reintroduced in Columbia River

Published: June 24, 2024
  • Biomark has provided RFID tags embedded in Chinook salmon and readers and antennas along dams and the Columbia Riverbed
  • The data will help a group of tribes, government agencies and utility companies to track whether the newly introduced fish can survive passing up and down the river, through multiple dams.

As part of an ambitious project to return Chinook salmon to the upper Columbia river basin, Merck Animal Health’s Biomark has been tagging thousands of fish so that they can be introduced to the river and tracked as they go to sea, and return up the river to spawn.

With data for RFID tags embedded in each fish, scientists hope to understand how well the fish are surviving in the wild, what conditions may be a challenge, and how to modify the reintroduction going forward.

As part of this effort, two Biomark technicians recently were up to their elbows in water and salmon fry (juveniles), inserting RFID tags into each young fish to create a unique, digital identity. In fact, they manually tagged 10,000 such fish in three days so that they can automatically be tracked as they are set loose from the Chief Joseph Hatchery in north central Washington state.

The RFID Project

The hatchery can produce up to 2.9 million chinook fry annually and is aimed at providing salmon for tribal ceremonies, meeting subsistence needs for tribal members, and increasing recreational fishing opportunities for all. The $50 million hatchery was completed in May 2013 and is located in Bridgeport, WA, next to Chief Joseph Dam.

Not all fish are expected to be tagged, just a representational percentage. Each fish’s rice-sized tag comes with a unique ID that links to its details in the system software, said Maxwell Reinhardt, key accounts, sales and customer service manager, Biomark and one of the fish tagging scientists.

Biomark brings technology to wildlife, in a singular business that leverages RFID technology to identify animals in their habitat. The vast majority of the Idaho company’s business is in the Northwest where salmon are threatened by the large number of dams in Columbia and tributary rivers. But its system is used to track sea turtles, birds, bats and sturgeons, each with an effort to better understand the animals, their health and environment.

Reintroducing Salmon in the Upper Columbia River Basin

Restoring salmon to the Upper Columbia is an ambitious project that includes the Confederated Tribes of the Colville Reservation, the Coeur d’Alene Tribe, the Spokane Tribe of Indians, the federal Bureau of Reclamation, Bonneville Power Administration (BPA), the Army Corps of Engineers, and the state of Washington.

Spanning decades, the dams that bring power to the area have blocked the spawning of migratory fish species that were once abundant in the river. The agencies are in a multi-decade process to bring the fish volumes back to healthy levels.

In fall of 2023, BPA entered an agreement with local tribes to reintroduce salmon in the upper Columbia River. BPA is providing $200 million over 20 years for projects involved in that reintroduction.

That effort requires keeping an eye on fish passage. While juvenile summer salmon are being released this season, when they return as adults, they will then need to be trapped and transported above the dams until more effective fish passage has been put in place.

With RFID in a significant percentage of the re-introduced fish, the researchers will have a view into how successfully the salmon return upriver after being out to sea. That includes juvenile migration studies and behavioral studies.

Tagging in Volume

The tagging of young salmon is part of the fish detection system called a PIT-tag array managed by state agencies, tribes and BPA. Fish such as salmon and wild steelhead have been listed as threatened under the Endangered Species Act and researchers have bees tasked to understand fish movement, populations and diversity in the wild to help increase their numbers.

For tagging, typically the fish are collected in the raceways, anesthetized so that the tag can be inserted in the abdomen when they are less than a year old, and measure about 65 to 85 millimeters long, said Reinhardt. Eventually, the same fish should grow to about a meter in length.

Each insertion is a manual process. The Biomark team members use a needle to insert the tag into the body cavity. As the fish heals, a layer of fat deposits seals around it, and the tag should stay with the fish for its entire life cycle. Each tag is read and linked to data about the fish’s size, as well as the date and location where it was tagged in the system software.

Following several days of healing, the salmon are trucked from the hatchery to the waters below the Chief Joseph Dam and released.

Heading Out to Sea

Biomark provided the hardware for the PIT-tag detection systems (RFID antenna arrays) installed at dams and other key locations where the tags can be read. For instance, dams with spill bays through which the salmon are routed come with antennas consisting of ferrite tiles and an external aluminum shield. This material allows the antennas to be placed within the steep bypass openings.

The PIT detectors come with readers and master controllers to serve up to 12 readers. Those antennas that aren’t installed at dams are typically on bottoms of streams.

The juvenile Chinook don’t embark on their journey to the sea for about six months, but when they do, they pass over the antennas which capture each tag ID and updates the status of that fish, indicating that it is proceeding through the process of swimming to sea.

Eventually the salmon, as adults, return upstream to spawn, which takes them back up the river. A percentage of fish will not return, having been eaten by a predator such as a sea lion or bass, or fished by humans.

Tracking the Return Home

Those that do make it upriver pass over the same RFID readers. At some dams, viewing windows with cameras are recording the fish as they swim through so that scientists can see the approximate size of each adult fish as its tag is read. They can then calculate how much each fish has grown since they were tagged.

The read data can help researchers identify which fish are thriving, and how well. For instance, if fry that were 65 millimeters when they were tagged only survive to adulthood at a rate of 20 percent—and larger fry had a higher return rate— that information could help strategize when they should be released from the hatchery.

The data is managed in the research collective’s software and shared among members. Biomark, at the same time, provides the tag IDs and related data for each fish that is fed into that software.

In the long term, as the reintroduction of salmon extends, the plan is to build fish ladders as some dams, to enable the adults to pass up and down the salmon autonomously. Another option is sending salmon over the dam in a “salmon cannon.” If they are successful at spawning upriver, a new generation of Chinook salmon may result in the wild.

In the meantime, the RFID tag read data can continue to be collected for all tagged fish passing along the Columbia and dozens of sites.

Sea Turtles, Birds, Snakes and More

Biomark provides RFID tags for a variety of wildlife, beyond fish. While fish as the most common tagged animal for the company, (about 300,000 tagged annually), they work with researchers, labs or agencies tracking animals like sea turtles, birds or even mammals.

“I come into work and every day it’s a new experience—I don’t know what am I dealing with today—will it be sharks, will it be hummingbirds, will it be fish, will it be snakes,” Reinhardt said.

Company officials have been in conversations recently with a team at Auburn University to provide the LF tags to be embedded in finches for studies about thermal regulation of the birds.

Biomark offers a tagging trailer with necessary tag insertion tools for small fish, but other projects may require the specific animal researchers or their technical staff to apply the tags. One use case has been embedding tags in bats to monitor their movement into and out of caves. Such efforts can help track health conditions of the animals who are subject to contagious diseases such as white nose disease.

While there are other wildlife technology companies, Merck officials note the Biomark brand sets itself apart because it offers a plug and play option offering its own reader antennas which it will install, tune and integrate with a reader and to meet the needs of the environment.

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