MAN AND THE SEA, II 65 



Anything the diver does that resembles the normal prey oF these predators 

 might cause them to bite. For example, blood in the water stimulates sharks 

 into a nervous frenzy called the "feeding mood" so that they will bite at any- 

 thing in and around the area scented with blood. The smell of blood leads 

 them to the prev, and when the victim or any object comes into range of their 

 poor evesight thev will almost always bite. This is a normal feeding pattern of 

 most sharks, which have a highly developed olfactory sense. For that 

 reason, carrying dead or wounded fish on a belt while swimming can also be 

 dangerous. 



Many fishes feed mainly by sight, and those dangerous to man are usually 

 the faster-moving fishes such as the barracuda. They usually hunt down their 

 prey with quick, darting strikes. Any splashing about the surface, especially in 

 water with poor visibility, may resemble a school of frightened fish or a 

 wounded fish, causing barracudas or other fishes to strike blindly. This is 

 almost like a reflex with them (Chapter 2). Such fishes as wahoo or tarpon 

 might possibly become dangerous in the same fashion. 



Bright, shiny objects such as rings or belt buckles look like the bright side 

 of some fish and attract predators. When fishes are hurt they often show their 

 light undersides. Having objects or clothing that flutter as the diver moves 

 through the water can be dangerous for the same reason. 



Diving at night or in water with poor visibility can be extremely dangerous 

 because many fishes such as sharks and fishes that would not normally attack 

 man do so under these conditions (barracuda, Chapter 9, and sharks. Chapter 8). 

 Here again, the diver enters the feeding pattern of fishes, for many fishes locate 

 prey at night by picking up vibrations of swimming movements with their 

 lateral line receptors (Chapter 2). These fishes pick up the vibrations of prey 

 moving through the water and strike in the direction from which they are 

 emitted. 



Some fishes have chemoreceptors on the skin of the body, and it is possible 

 a touch by a diver will emit a biting response in the direction of the touch. 



Of course, almost all animals on land or sea when cornered or wounded will 

 fight with every ounce of their strength. When a diver reaches into a hole for 

 a lobster there is a chance that he will be bitten by a moray eel. The eel sees this 

 move as an aggressive action and bites to defend itself. Toadfishes and wolf 

 eels can also be provoked into biting in this way. 



The killer whale, being an intelligent mammal, must be viewed apart. It is 

 particularly dangerous because of its liking for larger warm-blooded prey. 

 Luckily, it is rarely seen out of cold northern waters. Almost nothing is known 

 of its reaction to man under water. 



Aggressive animals dangerous to man: 



Some sharks; Large moray eels (when molested); Barracuda; Killer whale. 



Other large predatory animals which might be dangerous if man enters their 

 feeding pattern: 



Sawfish; Tarpon; Spearfishes; Giant jewfishes; Wahoo; Some other large 

 predators. 



