The present disclosure is directed towards determining, at sea, the respective weights of fish species that are part of a fish catch. By way of the present disclosure, images of a fish catch are taken using triangulation techniques involving stereo-photogrammetry. According to one embodiment, a method for estimating a total weight of a fish catch includes receiving a fish catch on a fishing vessel and capturing images of the fish catch. From the images, fishes are identified and the species to which the corresponding fishes belong are also identified. Using the images, lengths of the identified fishes as well as the total volume occupied by the fish catch are determined, which can be used to estimate the total weight of the fish catch.
