ODFW release - NEWPORT, Ore. – ODFW’S Marine Fisheries Research team is headed out to sea to search for old female rockfish, particularly black, canary and yellowtail rockfish.  The team, along with two collaborators from Oregon State University leave Newport Aug. 1 for Cobb Seamount, an inactive underwater volcano, 322 miles west of Oregon’s north coast.  Why these three rockfish species?  These three fish species are unique because, as they get older, most of the population are males. Scientists have also found that older fish are rarely caught in commercial or recreational fisheries.  This raises an important question: where are these older female fish? One possibility is that they move to offshore seamounts.  This unusual pattern also raises another important question: are older female fish still alive and able to reproduce?  If scientists cannot determine whether these older females are still part of the breeding population, it becomes much harder to estimate how many young fish will be added each year. These estimates are essential for setting fishing limits that keep fish populations healthy. Because commercial and recreational fishing are important to Oregon's coastal economy, collecting the best possible data is critical for making accurate stock assessments.  “Black, canary, and yellowtail rockfish have been documented at seamounts, including Cobb Seamount,” said Leif Rasmuson, Project Leader of ODFW’s Marine Fisheries Research Program. “But we just don’t know if old females migrate to those seamounts or if young fish arrive at seamounts due to fish larvae drifting to those areas.”  The researchers will try to answer several questions about black, canary, and yellowtail rockfish ranging from whether old females are at Cobb Seamount, and if so, how large is the population, and are they genetically related to nearshore populations. They will also examine if their diets differ from those that live in the nearshore environment, and affix satellite tags to learn if the fish remain at individual seamounts or migrate between seamounts.  It will take the team two days to get to Cobb Seamount, and they will spend two weeks conducting research. Cobb Seamount is an ideal place for this research with its biological diversity that supports extensive fish populations, mostly various rockfish species.  The team will use scientific fish finders and underwater video cameras to count rockfish species, along with hook and line gear to sample fish for length, age, genetic samples and stomach contents. A small number of black rockfish (or canary or yellowtail if caught) will get satellite tags to learn if the fish are moving among seamounts or between seamounts and the nearshore.  Once data is collected, researchers could have results in approximately six months.  ODFW Marine Fisheries Research team is headed to Cobb Seamount with two Oregon State University collaborators to search for old female rockfish. The crew will be on The Pacific Storm, a former commercial trawler gifted to OSU and reconfigured as an oceanographic research vessel.