SHARK VS SHARK

Pacific sleeper sharkvsBluntnose sixgill

Length, weight and bite evidence—plus context from a human, city bus and blue whale. Every number below carries its uncertainty with it.

LivingSomniosus pacificus×LivingHexanchus griseus
QUICK VERDICT

Pacific sleeper shark is about 1.46× longer by these reference values.

Pacific sleeper shark uses a 7 m upper reference, compared with 4.8 m for Bluntnose sixgill. Pacific sleeper shark's weight reference is about 1.54× heavier.

01

ON THE SAME SCALE

Human. Bus. Whale.
Pick your reference.

RELATIVE LENGTH · 0–24 METERS
APacific sleeper sharkreported near 7 m / 23 ft
BBluntnose sixgillreported to 4.8 m / 15.8 ft
REFAdult human1.8 m · about 80 kg

Length bars use upper comparison values and do not show body depth, tail proportion or typical adult size. A long thresher tail, for example, does not equal whale-shark body mass.

02

THE NUMBERS

Side by side.

MeasurePacific sleeper sharkBluntnose sixgill
Length referencereported near 7 m / 23 ftreported to 4.8 m / 15.8 ft
Weight referencelarge-animal estimate about 907 kg / 2,000 lbpublished to 590 kg / 1,300 lb
Bite forceNo dependable maximum foundUnknownNo dependable maximum foundUnknown
HabitatCold North Pacific, often deepDeep temperate and tropical waters
DietFishes, squid, marine mammals and carrionFishes, rays, seals and carrion
03

WHAT THE DATA CAN SAY

Size is not the whole animal.

Length and weight

Pacific sleeper shark is represented by reported near 7 m / 23 ft; Bluntnose sixgill by reported to 4.8 m / 15.8 ft. Large values often depend on indirect or incomplete records. Deepwater sampling is difficult, so upper records are sparse.

Bite evidence

Pacific sleeper shark: No standardized maximum is available. Bluntnose sixgill: No standardized maximum is available.

Living versus extinct

Both species are living, but record-sized individuals are rare. These upper references should not be read as normal adult size.

Ecology changes the matchup

Rare encounters make its maximum size less certain than familiar coastal species. Its six gill slits mark an ancient branch of shark diversity.

04

TRACE THE CLAIMS

Sources and limits.

Pacific sleeper sharkAlaska Department of Fish and GameBluntnose sixgillFlorida MuseumHow we standardize comparisonsRead the methodology →