AFSC Study on Alaska Corals

Researchers at the Alaska Fisheries Science Center say a five-year study pinpoints the slow growth of some Alaska corals, and the important implications this slow growth has for commercial fish species.

The study began with AFSC researchers diving into the North Pacific Ocean and tagging 93 coral colonies to learn more about the growth rate of some Alaska corals that provide important commercial fish habitats. Then every year for five years they went back to the bottom of the ocean to measure the size of the corals.

Their conclusions were published in January in the peer-reviewed, open-access online publication PLOS ONE. The web link is
Gorgonian octocorals are the most abundant corals in Alaska, and provide important structural habitat for managed species of demersal fish and invertebrates.

While 59 gorgonian species have been reported from Alaska waters, little is known about their life history characteristics to help determine their ability to recover from seafloor disturbance.

Based on data collected, the researchers concluded that it would take about 60 years for some of the gorgonian octocorals to grow to maximum size, and depending on the location and size of the parental standing stock, at least one, and possibly 10 additional years for recruitment to occur.

Researchers further concluded that colonies of these corals that are injured, perhaps chronically in areas of frequent disturbance, grow at slower rates. If the current trend of ocean warming continues, they said, these corals can be expected to grow more slowly, and the habitats they form will require more time to recover from disturbance.