Swordfish
Xiphias gladius
— Where the name comes from
Xiphias is from the Greek xíphos, the sword; gladius is the Latin for the short sword of the legionary. Two languages, the same weapon, repeated in the common name: the flattened, sharpened bill extending the upper jaw is the fish’s unmistakable signature.
— Facts
- Group
- Fish · Actinopterygii · Chondrichthyes
- Order
- Billfishes
- Habitat
- Open sea, from the surface to great depths
- Range
- All temperate and tropical oceans, and the Mediterranean
- Size
- 2–3 m including the bill, up to 4.5 m
- Diet
- Carnivore — fish and squid, often stunned with the bill
- Lifespan
- 9–15 years
— Characteristics
- 01
The blade-like bill, a third of the body long, cleaves the water and strikes into shoals of fish.
- 02
A special organ warms the eyes and brain, sharpening vision in cold deep water.
- 03
It is among the fastest fish: in bursts it is said to pass 90 km/h.
— What sets it apart
The swordfish warms its own eyes. Next to them sits a special organ that heats the retina and brain to 10–15 degrees above the surrounding water: in the cold, dark depths where it hunts, this lets it see fast movements that a cold-blooded eye would miss. The bill is not for spearing but for slashing through shoals, stunning or cutting prey before it is swallowed. It is a sword that strikes with the edge, not the point.
