This portal tracks the research and sea-going activities of the Fisheries Engineering and Acoustic Technologies (FEAT) Team from NOAA¿s Northwest Fisheries Science Center. Follow us as we use acoustics, trawling, and oceanographic sampling to learn about the Northeast Pacific Ocean.
In the previous post, I mentioned that we found larval hake, and wondered when we would find the adults that might be responsible for those larvae. Imagine how excited we were when we found adult hake just 54 nmi NNE of where we caught larvae in the bongo tow!
Our excitement was short lived.
The adults we caught, with an average nose-to-tail length of 37 cm, had not spawned. The male fish were more developed than the females, something we frequently see. But, while these fish might be close to spawning, neither sex had spawned. Huh.
Assessing the maturity of Pacific hake is done visually at sea. As part of the sampling, the Wet Lab Biologists assess the development of hake ovaries (female) and testes (male). The photo shows the ovary from a 49 cm female who isn’t quite ready to spawn. Some of the ovaries and testes are dissected out, preserved in formalin, and brought back to the lab for closer histological analysis with a microscope. The histological work-up can confirm the at-sea maturity assessment, but also gives a closer look at details like how many eggs a female can produce or whether female hake spawn all of their eggs at once or a little at a time. Important information to know for such an important species.