“To the human ear a lion roar is audible from five miles but lions can probably hear another lion roaring from further than that.”
So it is probably more than 5 miles if you are a lion, say perhaps 6 miles depending on conditions.
References for the above statement quoted verbatime: Mel and Fiona Sunquist authors of Wild Cats Of The World at page 294, in reference to (1) Guggisberg CAW 1963 Simba The life of a lion New York Clinton Books and (2) Schaller GB 1972 The Serengeti lion Chicago University Press and (3) Stander PE & Stander J 1988 Characteristics of lion roars in Etosha National Park Madoqua 15: 315-318.
When lions are together they can synchronise their roars so that they follow one another. This lengthens and extends the sound and increases the effect on neighbouring lions. They may roar in response (references: as above).
Lions usually roar when standing and when one starts the others are often stimulated to join in (references: as above).
Male and female
Males and females roar but the roar is deeper and louder (references: as above).
Depending on circumstances, the lion roar is believed to be (1) a territorial display and/or (2) a spacing mechanism and/or (3) ‘a device to ensure group cohesion and facilitate contact’ and/or (4) all of these.
References to this section: Wild Cats Of The World at page 294 in reference to (a) 1 and 3 above plus (b) Schenkel R 1966 Play, exploration and territoriality in the wild lion Symp Zool Soc Lond 18: 11-12 and (c) Ulmer F 1966 Voices of the felidae Int Zoo Yrbk 6: 259-262 and (d) Smuts GL 1982 Lion Johannesburg Macmillan.
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