Ocean Bottom Temperatures are Key to Pacific Cod Numbers
A federal fisheries study focused on the influence of water temperature on egg hatching success concludes that the dramatic loss of Pacific cod in the Gulf of Alaska in 2019 was due to lack of optimal spawning habitat on the ocean bottom.
The NOAA Fisheries study, led by biologist Benjamin Laurel, connected low numbers of Pacific cod larvae, juveniles and adults to loss of spawning habitat in the 2013 – 2016 marine heatwave, known as “the Blob” – the largest warm anomaly ever recorded in the North Pacific.
Loss of optimal habitat for the Pacific cod eggs occurred during and immediately following the heat wave, causing a significant ecological as well as a significant economic impact on the second most valuable commercial fishery in Alaska.
Also worth noting, researchers said, is t...