A new tool developed by NOAA Fisheries scientists allows researchers to pinpoint the river system that individual Chinook salmon come from, thereby enabling more precise management and protection of threatened and endangered populations.
“It’s like giving every fish a unique genetic fingerprint,” Donald Van Doornik, a NOAA Fisheries biologist and lead author of a paper published July 8 in the North American Journal of Fisheries Management, explained.
“We can use this fingerprint to figure out where that fish came from by comparing it to other fishes’ DNA,” he added.
A Sept. 26 announcement by NOAA Fisheries noted that by identifying specific Chinook populations contributing to mixed-stock fisheries, they’ll be able to design more effective conservation and management strategies.
Developing comprehensive genetic databases for species with wide geographic ranges, such as Chinook salmon, has been challenging, according to NOAA, because the species has a vast geographic distribution and diverse genetic makeup.
The limitations of existing genetic data and technology have also hindered the development of a reliable, range-wide genetic stock identification database for Chinook salmon.
Other researchers developed a coastwide genetic database for Chinook salmon using microsatellites, which are simple repeats of genetic bases in the genome, more than a decade ago.
This technique has been difficult to standardize among labs and provides limited information compared to new methods, NOAA researchers said. The updated database uses newer technology that surveys genetic sequences and individual base differences among individuals and populations.
The genome itself is a set of genes or genetic material present in the cell or organism that provide energy for the cell.
Development of this new tool involved federal, state, tribal and academic researchers across the West Coast collecting genetic data from various sources across the Chinook’s entire geographic range.
Then they assembled a genetic database that scientists can use to accurately identify a salmon’s origin. Rigorous testing and simulations ensured the database’s reliability. Finally, they employed a hierarchical analysis approach to pinpoint a salmon’s specific home.
Researchers developed a standardized genetic reference for Chinook by collecting, standardizing, and analyzing the DNA of thousands of salmon from various populations.
By accurately identifying the origin of individual salmon managers are able to make informed decisions about harvest quotas, protect endangered populations and monitor the health of different stocks.
The information can also be used to study migration patterns, genetic diversity and the impact of specific fisheries and environmental factors on salmon populations.