Assessing the biodiversity of deep-sea large crustaceans through fishing ports

The biodiversity of the deep-sea fauna is being assessed worldwide. Most related studies have been based on scientific cruises using research vessels to conduct samplings, including remotely operated vehicles (ROVs) and human-occupied vehicles (HOVs) or fishing boats. In coastal regions with steep continental slopes, deep-sea fisheries have often developed. Catches in fish markets in these regions can provide an economical approach to assessing deep-sea biodiversity. A key concern is determining the number of samplings of fish markets required to obtain representative samples for measurements of biodiversity. We describe techniques for sampling large crustaceans in fish markets by analysing the results of daily visits (up to 30 days) to two deep-sea fishing ports in Taiwan. It is shown that when the study area has a high biodiversity, at least 15–20 samplings will be required to obtain representative data.