Photogrammetry Introduction l Projects l Camera Systems l Aircraft l Image Interpretation Systems l The Digital Age
At the end of an aerial field project, we have several rolls of film to examine. We look at each frame on a light table outfitted with a binocular microscope, and count the number of animals in a particular school. We also systematically measure a sample of individual animals using ImagePro software. This gives us morphometric data that help us to determine which stock those animals come from, as well as their condition (such as emaciation or pregnancy, which is especially evident in large cetaceans like gray whales). Since the location of each photographic pass is known, we also gain valuable information about stock distribution, morphometric differences between stocks, and reproductive trends (e.g. ratio of calves to adults.) By measuring calves of a known species, for which we know the growth rate, we can calculate the birth dates of those calves, which indicates reproductive timing of the dolphins in that population.