Surveying of fish stocks is possible through the use of cameras. One example of an important use is for estimating scampi abundance at depths of over 400 m.
Cameras can be low cost. For example, GoPro cameras have been increasingly used to survey fish to understand fish behaviour in and around sampling gears (gear used for research purposes, such as nets or traps).
A study undertaken in the Persian Gulf by NIWA used GoPros to estimate fish abundance and behaviour in pots and at baited underwater video stations.[1] The research found that counts with use of the cameras were consistent with catch sampling, making it an effective method. Additionally, useful observations on behaviour could be made – like a species’ disposition to guard bait in traps, which in turn could make it more easily catchable. This information is important when assessing CPUE and consequently the abundance of a species (as discussed in ‘The relationship between catch per unit effort and abundance’).
Cameras present a practical sampling alternative in areas where fishing is prohibited – for example, in marine reserves. Regulations need to adapt to enable video footage to be used as evidence when monitoring fisheries and fishing methods.
Go-pro observations on a baited underwater video station (top) and a trap (bottom).
References and footnotes
[1] Finucci, B. et al. (2019) Diversity, abundance, behaviour, and catchability of fishes from trap catch and underwater video in the Arabian Gulf, Fisheries Research, 220, p. 105342.