In Search of “Little” Fish to Further Conservation Research
Aquarium staff traveled to the Pacific Northwest to aid in an underwater survey on young rockfish.
Aquarium of the Pacific Aquarists Brooke Hernandez and Heidi Johnson walk to shore after SCUBA diving during an underwater rockfish survey. Credit: Aquarium of the Pacific
April 30, 2025
Rockfish are important to the marine ecosystems of Washington state and Canada. Their roles as both predator and prey, coupled with their long lifespans (some species can live over one hundred years), make rockfish valuable indicator species to monitor. Indicator species are organisms whose presence, absence, or abundance can reveal information about the health of an ecosystem. For that reason, Aquarium of the Pacific Aquarists Brooke Hernandez and Heidi Johnson traveled to the Pacific Northwest to join an underwater effort to survey rockfish.
The goal of the survey was to monitor the presence of rockfish in their first year of life (young-of-the-year) and juveniles. Of the rockfish species found in the surveyed region, two species of rockfish, the yelloweye rockfish (Sebastes ruberrimus) and the bocaccio rockfish (Sebastes paucispinis), are of most concern because the fish are threatened and endangered, respectively. In addition to being a major part of the ecosystem, rockfish are also popular for both commercial and recreational fishing.
Hernandez and Johnson dove to survey underwater areas in the Hood Canal near Hoodsport, central and south Puget Sound, and in the Strait of Georgia in Vancouver, Canada. Young-of-the-year rockfish can be identified by their smaller size at about ten centimeters (nearly four inches). The surveys performed are part of a long-term monitoring program, which is still ongoing. Results are recorded in a database that will help researchers notice any significant changes in rockfish populations over time. However, there was an average amount of juvenile rockfish that were seen this time compared to previous survey years. The team also observed a mix of rockfish species, which overall amounted to seeing an average amount of rockfish for this time of year compared to other survey years during the same period.
Hernandez and Johnson also saw a lot of invertebrates such as sea stars, anemones, sea cucumbers, and nudibranchs. The aquarists even saw a giant Pacific octopus curled up in a den, as well as many endangered sunflower sea stars in the sea grass beds.
A yellow eye rockfish in the Aquarium’s Northern Pacific Preview habitat. Credit: Aquarium of the Pacific
You don’t have to travel to the Pacific Northwest to see and learn about rockfish. The Aquarium of the Pacific features rockfish in some of its habitats. Guests can see the yelloweye rockfish in our Northern Pacific Preview on the first floor in the Great Hall. The bocaccio rockfish can be found in our Northern Pacific Gallery’s Surge Channel and Rocky Reef habitats. There are also other rockfish to discover as you visit the Aquarium.
