Humpback and Blue Whale Photo-ID Project – US West Coast


Two humpback whale flukes show the wide variation in markings

The dorsal fin and pigmentation pattern on the side of blue whales provide a fingerprint for identification.

Cascadia Research conducts long-term research on humpback and blue whales both along the West Coast of the United States as well as off Central America. We began this photo-identification research in 1986 and have continued annual surveys each year since. This photo-ID effort serves as the basis for the abundance estimates and trends for both these species off the US West Coast. Cascadia also relies on contributions from a number of opportunistic sources (including citizen science) as well as collaborators to provide sighting information and photo-IDs. Through 2018 the humpback catalog includes more than 5500 unique individuals with just over 49,000 encounters, while as of 2018 Cascadia’s blue whale catalog includes over 2500 individuals with over 16,000 encounters. In 2018 Cascadia Research under a contract with the National Oceanic and Atmospheric Administration (NOAA), Southwest Fisheries Science Center (SWFSC) took park in the California Current Ecosystem Survey (CalCurCea). For this project Cascadia followed a NOAA ship conducting line transects and surveyed areas of known whale concentrations. Cascadia was also the principal organization conducting and coordinating the SPLASH humpback whale research effort from 2004-2006. Cascadia was conducting the matching but also coordinated all efforts for US West Coast and Central America.


The objectives of our research include:

  • Determine the abundance of humpback and blue whales off California
  • Determine trends in these populations
  • Identify critical feeding habitats that need protection
  • Monitor potential human-caused threats to large whale populations off California including ship strikes and sonar impacts

See additional information in these reports and publications by topic:

Humpback and blue whales off California, Oregon, and Washington

Underwater behavior of blue, fin, and humpback whales whales using suction-cup tags , fin, and humpback whales whales using suction-cup tags 

Humpback whale research in Central America

To learn more about these research efforts please see the following:

SPLASH research project