The Ecosystems and Fisheries-Oceanography Coordinated Investigations Program
At NOAA’s Pacific Marine Environmental Laboratory (PMEL) and Alaska Fisheries Science Center (AFSC), researchers are hard at work developing models to forecast changes in fish populations.
One example of a program that has been successful in forecasting fish populations is the Ecosystems and Fisheries-Oceanography Coordinated Investigations (EcoFOCI). EcoFOCI is developing indices of ecosystem status and designing forecast models to predict future states of the North Pacific Ocean’s ecosystems and individual populations of living marine resources.
In order to forecast fishery abundance within a marine ecosystem, scientists need to know the number of fish eggs laid for a specific species of fish and their germination and survival rate. Scientists also need to know the type and amount of food available to each species of fish, the diseases that they will face, where they go and what they will encounter (currents, predators, fishermen), changes in ocean climate that affect the species and their environment, and when and where they will be during harvest time.
For more than 20 years, EcoFOCI has been researching Alaskan walleye pollock, one of the most valuable commercial fishes in the world. Although there were still some unknown things about the species (e.g., where they go after they grow to be juveniles, how many different things there are for them to eat and be eaten by), EcoFOCI scientists felt they knew enough about the species and their environment to begin forecasting in 1992, eight years after studies began. The population forecast predicts total pollock recruitment to the fishery (abundance when the fish are two years old) from information collected during the fish’s pre-spawning, spawning, egg, larval, and early juvenile developmental stages (about a 5-month period). Population forecasts have achieved sixty percent accuracy since they began in 1992.
Population forecasting has been increasingly successful; however, in order to continue improvement over the next twenty years, two things must occur. First, data on the ability of pollock to survive to recruitment age must be collected, as this information is currently lacking or inaccurate. Next, this more complete data set must be incorporated into an appropriate mathematical model for population forecasting.
In present-day management, predicting a single species such as pollock falls short of ecosystem management requirements. Fragmented, single-species approaches do not take into account the complexity of the many ecosystem interactions that produce population changes. For instance, an increase in the amount of food would lead to the conclusion that more pollock would survive to recruitment age. However, the increase in food may support other fish that are competitors of pollock or even consumers of pollock.
Modern-day management of the kind supported by EcoFOCI promises that future marine resources will be abundant and ecosystems will be healthy. With continued research and observations, seafood lovers for generations to come will be able to enjoy their fare.