Smallspotted catshark Scyliorhinus canicula and nursehound Scyliorhinus stellaris iNaturalist observations in the UK

This dataset contains metadata for Scyliorhinidae images collected from the open access platform iNaturalist. Inclusion criteria were record dates between 1st January 2008 and 31st October 2025 and locations within the UK. An initial total of 2608 images were filtered to yield 626 images of smallspotted catsharks Scyliorhinus canicula, and 65 images of nursehounds Scyliorhinus stellaris. These were then visually assessed for colour aberrations including hypomelanosis and hypermelanosis. Each record in the dataset provides: [observation_ID] unique code assigned during this study [observed_in] observation date [url] direct url to access original image at source [latitude] latitude of record [longitude] longitude of record [quality_grade] image quality according to iNaturalist ranking system [shark (Y or N)] whether image shows a shark [included_in_analysis (Y or N)] whether image was retained in study analysis [hypomelanosis present] whether specimen was assessed as showing hypomelanosis [hypermelanosis present] whether specimen was assessed as showing hypermelanosis Records retained in study analysis also provide: [view] angle of view of shark [amount_visible_scale] semi-quantitative estimate of proportion of body visible [deterioration_scale] semi-quantitative estimate of body condition [image_quality] qualitative image ranking [hypomelanosis_star_rating] qualitative reporting confidence based on deterioration and image quality Users of this dataset should respect the original licensing terms of each image when accessing them through the provided URLs.