Photographic Identification (Photo-ID) is one of the most powerful and useful tools we use
Photographic Identification (Photo-ID) is one of the most powerful and useful tools we use to document, research and understand gray whales that visit Laguna San Ignacio each winter. Fortunately, gray whales have distinctive marking on their skin that change little over time. They also acquire white scars from injuries, barnacles, and killer whale tooth “rake marks” which aid in the identification of individuals. These natural markings are permanent natural “tags” which stay with each whale throughout its life.
The re-identification of individual whales over time provides information on the number of times a whale returns to the lagoons of Baja California over many years, and can give us a minimum estimate of a whale’s age.
By photographing breeding female whales each time they come to Laguna San Ignacio with or without a new calf, we can estimate the “calving interval” or the average number of calves produced each year, which is an important index of reproductive health for each individual female whale.