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8.2.3 Automating Bearing and Distance Measurements in Big-Eye 25 x 150 Binoculars and Recording/Saving Images


Summary: Conducting marine mammal stock assessments is a core function of the agency to provide the scientific basis for marine mammal conservation. Traditional methods for estimating abundance, density, and distribution for multiple cetacean species rely almost exclusively on visual surveys conducted on-board ships. Visual surveys involve the use of “Big-Eye” 25 x 150 binoculars to manually scan for cetaceans to a maximum distance of about 11-13 km from the ship. Scanning is done by trained observers who locate and identify species and estimate group sizes, which are ultimately used to estimate population abundance and in the development of habitat models. Two key measures are obtained using the binoculars, which include bearing and reticle distance to the sighted animal. While the bearing measurement is easy to obtain with accuracy, the reticle distance however, is at best an estimate due to the motion of the vessel and sea state. In addition, reticle distance measurement errors can be compounded at distance and when the target animal is being tracked. Similar to theodolite readings obtained on land, an automated reading of bearing and reticle distance measurements would reduce or eliminate uncertainty while recording cetacean sightings. Further, a second issue is the lack of any photographic or video evidence of what the observer sees through the binocular. The availability of an image or video would help to verify species identification in situations where the animal is too far to identify or close-in approaches to verify species identification is not possible.


Project Goals: There is a need to design, test, and make commercially available Big-Eye binoculars that can digitally show reticle measurements and bearings as the binocular is swiveled by the observer and simultaneously be recorded in a computer database. A secondary goal is the ability to obtain images or video of the observer visual field during a sighting or tracking of animal.

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