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Why is electrical communication in freshwater fish limited to short distances?

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Animals communicate by sending and receiving signals. For example, a mother dingo (Canis lupus dingo) can communicate certain types of information to her pups by using tactile signals conveyed through grooming. — Animal communication Animals communicate by sending and receiving signals. For example, a mother dingo (*Canis lupus dingo*) can communicate certain types of information to her pups by using tactile signals conveyed through grooming.

Electrical communication in freshwater fish is limited to short distances—typically about 1 metre (3.3 feet)—primarily due to the high electrical resistance of fresh water combined with the relatively low voltages produced by the fish.1

While certain freshwater fish, such as the mormyrids of Africa and the gymnotids of South America, have evolved specialized bioelectric organs to generate signals for navigation and social interaction, the physical properties of their environment constrain the range of these signals. Because fresh water is a poor conductor of electricity compared to saltwater, the electric fields generated by these fish dissipate quickly, restricting effective communication to the immediate vicinity of the sender.21