How do water temperature and overall climate changes impact marine life? Active Pacific Northwest REEF volunteer surveyor, Curtis Johnson, recently co-authored a new paper that seeks to answer this question for one species of interest, the Giant Pacific Octopus (GPO). The paper, published in the scientific journal Marine and Freshwater Research, is titled "Sea-surface Temperatures Predict Targeted Visual Surveys of Octopus Abundance". Johnson and co-author, D. Scheel, used a variety of data sources, including data collected by REEF citizen scientist surveyors through the Volunteer Fish Survey Project, to evaluate GPO population trends in the Pacific Northwest.
They found large changes in GPO abundance linked to average water temperatures. GPO sighting frequencies ranged from 11-39%. For every additional degree increase of 4-year average temperatures, the Puget Sound GPO sighting frequency dropped about 19 points - a loss of about 75% of typical diver sightings for every degree. The authors also noted that of the many datasets they used to conduct the analysis, the REEF dataset provided the most comprehensive information on GPO populations and the strongest correlations between GPO sightings and temperature changes.
Because the REEF Volunteer Fish Survey Project covers such a large geographic area over such a long period of time, it is proving an invaluable and irreplaceable tool for monitoring and better understanding the impact of climate change on marine species. Visit www.REEF.org/db/publications for summaries and links to full papers on all research publications that have come from the REEF database.