Technology is helping to transform monitoring methods that are used to monitor species that live in benthic – or ‘bottom’ - habitats. In the past, monitoring was almost always carried out through visual surveys conducted by scientific divers, equipped with a slate and a pencil, who took note of all of the target categories present within a given in a ‘transect’ area.
Today, underwater photography is playing an increasingly important role in these ongoing survey efforts. Modern cameras, equipped with high-definition sensors (up to 40 million pixels), high quality optics, as well as large capacity memory cards (practically no limit to the number of photos), allow for a significant increase in the amount of data that is collected during a trip and further, provides much more precise information to be obtained for the given environment. The extraction of data from the digital images (percentages of coral cover, species richness, etc.) is carried out in the laboratory. The other advantage of photography is that it can be used to archive the data, allowing us to return to the images to complete the extraction of information or to visually compare a site from one year to another.
Modern cameras also allow for automatic data collection in rapid sequence, which is increasingly used to characterize habitats in 3 dimensions; several thousand photographs are taken with a minimum of effort in the field, and then analyzed in the laboratory for several hours by powerful computers to build a 3-dimentional image of the reef (see article 100 island training).