The Size of the Sperm Whale

The species name is Physeter catodon.  Another name which appears in the literature for the same species is Physeter macrocephalus which refers to the sperm whale's large head.

Adult males seem to range from 30 feet (9.15 m) to 50 feet (15.24 m) in length, but mention is found in older accounts of lengths reaching 55, 60, 70, 80, even 90 feet.  A contemporary account at a whaling station in northern Peru described a 52 1/2 foot (16 m) long sperm whale, 7.54 feet (2.30 m) thick which weighed an estimated forty-two tons (Rose, 1957).  A sperm whale over 45 feet (13.7 m) is now rare.  The accounts of bigger ones mostly date to the 18th and 19th centuries and referred to single, abnormally large, bull sperm whales, the recording of which in some instances may have been somewhat misjudged in the excitement of the catch.  Females are smaller, 30 feet (9.15 m) to 40 feet (12.2 m) usually.  A newborn calf is approximately 13 feet long (3.96 m).

The weight of a forty foot sperm whale is about 17 metric tons (18.73 short tons or 37,540 lbs.).  Early whalers estimated that larger whales weighed about "a ton a foot" but, with some lucky exceptions, this was mostly guesswork (Ellis, 1980).

There are larger whales than the sperm, but the sperm whale was the main target for oil over many years.  It is the sperm whale that most of us call to mind when we think of these denizens of the seas.  Moby Dick of Herman Melville's 1851 novel was a whitish sperm whale.  Sperm whales can have white spots of varying sizes ranging from local mottles to large areas, particularly on the belly.   Gaskin (1972) photographed a 52 foot male sperm whale on a ship's flensing deck which appeared to be nearly white (at least it had "an unusual amount of white on the head and flanks").