Gray Whale Photographic Identification Catalogs

Gray whale “Photo-Identification represents an on-going research activity within Laguna San Ignacio that has continued intermittently since it began in 1977. The LSIESP continues to obtain and contribute photographic identification data on the gray whales that visit Laguna San Ignacio each year.

Researchers Conducting Photo IDsGray whales possess individually unique pigmentation and markings that can be used to report the presence of specific individuals. Photographs of the whales backs are taken with 35 mm digital cameras with 75-300 mm telephoto zoom. Any scars or other conspicuous natural markings are also photographed. Individual whales are distinguished by comparing the natural markings around the dorsal region of the whale, including the shape of the dorsal ridge and “knuckles”. Markings include pigmentation of the skin, mottling, scarring, and barnacles, which are different among individual whales.

White spots are good marks for photo identification

Beginning in 2003, Jorge Urban R. and Steven Swartz began an effort to recover, archive, and digitize historical photographic identification data obtained by previous researchers working in the gray whale breeding lagoons of Baja California. To date this effort has resulted in the development of a photographic database and archive containing over 6,000 gray whale images obtained since the early 1970′s. These data are archived and managed in an interactive database that allows searching and matching of photographs to identify individually distinctive whales, and determine re-sighting rates within and among years.

Primary information obtained from these analyses include estimates of:

  • Annual return of known individual whales to Laguna San Ignacio.
  • Movements and minimum duration of stay of whales within the lagoon.
  • Calving rates for known females (per capita production index).
  • Cumulative number of gray whales that visit and utilize Laguna San Ignacio each winter as an index of the importance of this lagoon as a habitat for gray whales.
  • Proportion of “skinny whales” observed – those that appear to be suffering from nutritional stress.

The best photographs from the right and left sides of each whale (for each sighting) are selected and added to a digital catalogue for the year that the photographs was obtained. Separate catalogues for mothers with calves and single whales are maintained at the UABCS-LSIESP laboratory in La Paz, Baja California, and published on this website.

Investigators photographing gray whales are welcome to review these on-line catalogues for matches with their photographs of gray whales. If they find a photograph that matches a whale that they have also photographed, researchers are asked to contact us to arrange for the exchange of information on the date, time, and location that the whale was photographed in Laguna San Ignacio.

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