Earthwatch volunteers and staff collect data in three ways:
1. Photographic Data:
Photographic documentation involves photographing all the individual whales
encountered during daily vessel surveys. High speed black and white film
is used in a 35mm camera equipped with a 300 mm lens. The areas to be photographed
on an orca are its distinguishing features-the dorsal fin and saddle patch.
To get the appropriate photograph, the orca has to be parallel to the vessel
and at a distance no closer than 100-200 feet. The photographs are developed
and printed at the shore-based research facility on San Juan Island. Identification
of each frame is done by comparing the print with a catalogue of the members
of the Southern Resident Community. The catalogue is updated annually to
reflect births, deaths, matrilineal genealogies, and changes in dorsal
fins or saddle patches. The photographs are also used to assess signs of
poor health like sunken blowhole areas.
2. Observational data written down in logs:
While on shore or on the boat, observational logs are kept. Logs kept include:
a. Behavior log listing the behaviors and individuals doing those behaviors,
b. Boat log listing the location, number of boats, configuration of boats,
and the whales' configuration, and
c. Marine mammal log listing the species seen and their location.
The data from each of these logs is entered daily into the computer using
database software.
3. Acoustical data using hydrophones:
Hydrophones are used to detect when there is vocal activity and when there
is this evidence, tape recordings are made for future analysis.
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