Popis: |
Despite the importance of calanoid copepods to healthy ecosystem functioning of the Arctic Ocean and Subarctic Seas, many aspects of their biogeography, particularly in winter months, remain unresolved. At the same time, online databases that digitize species distribution records are growing in popularity as a tool to investigate ecological patterns at macro scales. The value of such databases for Calanus research requires investigation - the long history of Calanus sampling holds promise for such databases, while conditions at high latitudes may impose limits through spatial and temporal biases. We collated records of three Calanus species (C. finmarchicus, C. glacialis, and C. hyperboreus) from the Ocean Biodiversity Information System (OBIS) and the Global Biodiversity Information Facility (GBIF) providing over 230,000 unique records spanning 150 years and over 100 individual datasets. After quality control and cleaning, the latitudinal and vertical distribution of occurrences were explored, as well as the completeness of informative metadata fields. Calanus sampling was found to be temporally and spatially biased towards surfacemost layers ( |