ABSTRACT
The technique of finding suitable shark repellents should be to collect known benthic invertebrates that are the most highly toxic to fish and test crude extracts from them with a few species of sharks. The plethora of toxic marine organisms in tropical coral reef ecosystems would make the probability of discovering effective shark repellents in the near future very high. However, the most difficult problems to overcome include the prevention of rapid chemical dilution of repellents in the open sea and the prevention of shark attacks in progress. Evidence from approximately 1000 laboratory and field experiments and underwater observations in many regions of the world indicates that the intensity of fish and shark predation and rasping on the shallow-water hard benthos and the incidence of toxic benthic marine invertebrates vary inversely with latitude. The turkey baster was rinsed in seawater then filled with fresh seawater and emptied underwater near the snout of the second shark without a reaction.
