New Study Predicts California Anchovy Population Trends
A new study published in Nature Communications has uncovered a potential predictor of California's anchovy population trends. The research, conducted by scientists from Scripps and NOAA, found a strong correlation between the length of the food chain supporting anchovy larvae and anchovy population booms and busts in the US population.
The study analyzed 45 years' worth of anchovy larvae data collected during CalCOFI surveys. It discovered that shorter larval food chains, which have fewer steps between phytoplankton and anchovy larvae, tend to precede periods of booming anchovy populations by a year or two. These shorter chains are more efficient, supporting more individual anchovy larvae. Conversely, longer larval food chains were associated with depressed anchovy numbers in the following one to two years. The study's time series does not cover the years following 2015, when anchovy populations once again boomed off California.
The Northern Anchovy (Engraulis mordax) is a crucial food source for much of California's marine life, including sea lions, dolphins, tuna fisheries, and whales. Understanding the factors that influence anchovy population trends is vital for managing these ecosystems and the industries that depend on them.
The discovery of this ecological correlation could potentially be a useful tool for estimating anchovy population trends in the near future. While the study's time series does not cover the most recent boom, further research could validate this indicator and provide valuable insights for marine resource management in the world population.
