Paz Sampedro, member of the Working Group for the Bay of Biscay and the Iberic Waters Ecoregion (WGBIE)
‘The probability of one fish being caught is called ‘catchability’. In simple words, if there is a single pass of a trawl net through an area and one tenth of the monkfish is removed, then the catchability of monkfish is 0.1. Several factors may influence catchability, three important ones are the probability of a fish being in the area, the efficiency of the gear, and the probability of one fish present in the area of being caught.
Catchability is a helpful term in fishery science. It is widely employed in the evaluation of stock status, it is the parameter used to calculate the absolute abundance of a stock from abundance indices. Although historically, catchability has been assumed to be constant, it is known that it can increase or decrease over time. New approaches allow incorporating time-varying fishery catchability, which will make it possible to have a more precise evaluation of the stock status.’