Tuesday March 5, 2024
KYUK —
A new analysis of nearly 25,000 fish scales offers more evidence that the millions of pink salmon churned out by Alaska fish hatcheries could be harming wild sockeye salmon populations when they meet in the ocean, according to the scientists who authored the study.
The new peer-reviewed paper, published this week in the ICES Journal of Marine Science, analyzed growth rates that could be deduced from the fish scales, similar to trees’ yearly growth rings.
The paper was built on a unique aspect of the life cycle of pink salmon, which are primarily targeted by commercial fishermen: Their abundance is high in odd-numbered years, and lower in even-numbered years. Those booms and busts allowed authors Peter Rand and Gregory Ruggerone to tease out whether sockeye salmon — which are more highly valued by sport and personal use fishermen — were growing at lower rates during odd years, when pink salmon are more numerous.