Using Community Science and Photo-Identification to Assess Cetacean Skin Health in the Northern Colombian Pacific

The skin, as the outermost layer of the body, is in direct contact with the environment and serves as a critical indicator of both environmental and host health. While diseases naturally occur in all living organisms, including cetaceans, anthropogenic pressures can further deteriorate the skin health of marine mammals. However, the scarcity of direct studies on live cetaceans makes obtaining information about their skin health challenging. To characterize skin lesions and their frequency in cetaceans within the Gulf of Tribugá, in the northern Colombian Pacific, a total of 1,931 photographs of cetaceans in the Nuquí maritime area were collected between August 2020 and June 2023 through a community science program promoted by R&E Ocean Community Conservation in which local fishers are trained as community scientists. The species recorded were Delphinus delphis, Megaptera novaeangliae, Orcinus orca, Tursiops truncatus, Stenella attenuata, Stenella longirostris, and Steno bredanensis. The species most affected by anthropogenic marks and pathogenic lesions was M. novaeangliae, whereas the species showing the lowest number of visible lesions were D. delphis and S. longirostris. T. truncatus was the species exhibiting the highest number of natural rake marks on the dorsum, while O. orca showed no evidence of anthropogenic marks or pathogenic lesions. These variations in skin health are hypothesized to result from species-specific behaviors as well as intra- and interspecific interactions. This study represents one of the first attempts to assess cetacean skin health in the northern Colombian Pacific, indicating an overall healthy condition among individuals in the Gulf of Tribugá.