Shark detection research

This type of area mitigation aims to detect sharks. For example, drones, planes, helicopters, blimps, shark spotters on land, or listening stations to detect tagged sharks.

Shark detection strategies are not designed to repel or deter sharks, but to spot or track sharks. We can assume that spotting/tracking sharks helps us to mitigate shark bites in theory, but in reality, we do not know that this is true. This is important to keep in mind while reading shark detection studies.

The research

Beach safety: can drones provide a platform for sighting sharks

This study assesses the ability of drones to detect shark analogues (shark cut-outs) in the lab versus in real-time. Detection rates were significantly higher in the laboratory video analysis (50%) than the real-time drone pilot (38%). Drones were found to be a cost-effective option, and can operate in a range of environmental conditions. But few analogues were seen below 2m water depth.

Butcher, P. A. et al. Beach safety: can drones provide a platform for sighting sharks? Wildlife Research 46, 701-712 (2020).

Shark detection from aerial imagery using region-based CNN, a study

Three network architectures were used to identify and detect sharks (Zeiler and Fergus (ZF), Visual Geometry Group (VGG16), and VGG_M). VGG_M performed the best, with an average precision of .904 (out of 1) for detecting sharks.

Sharma, N., et al. (2018). Shark detection from aerial imagery using region-based CNN, a study. Australasian Joint Conference on Artificial Intelligence, Springer.

Shark spotters: successfully reducing spatial overlap between white sharks (Carcharodon carcharias) and recreational water users in False Bay, South Africa.

The shark spotting program aims to reduce humans and sharks sharing the same space. Spotters are based on land to watch for sharks in the coastal area. Flags are flown to inform water users of shark presence. When the white flag was flown (signifying the highest risk), the number of water users significantly reduced.

Engelbrecht, T., Kock, A., Waries, S. and O’Riain, M.J., 2017. Shark spotters: successfully reducing spatial overlap between white sharks (Carcharodon carcharias) and recreational water users in False Bay, South Africa. PloS one, 12(9).

Experimental evaluation of shark detection rates by aerial observers

This study assessed the rate that fixed-wing and helicopter observers could sight shark analogues (shark cut outs). There were more sightings at shallow depths (~ above 2.6 m). The sighting rates were low (12.5% and 17.1% respectively).

Robbins, W.D., Peddemors, V.M., Kennelly, S.J. and Ives, M.C., 2014. Experimental evaluation of shark detection rates by aerial observers. PloS one, 9(2).