Their eyes are heated to temperatures measured between 10 and 15 °C (18 and 27 °F) above the surrounding water temperature; this heating greatly improves their vision and, consequently, their predatory efficacy. [14][15]

While swordfish are coldblooded creatures, they have a unique heat regulation system that warms their brains and eyes, allowing them to hunt in colder waters effectively.

Jan 10, 2005 · Zoologists have answered the intriguing question of why swordfish keep their eyes warm while the rest of the body remains resolutely cold-blooded: it's all the better to see their prey with.

Jan 10, 2005 · Swordfish heat up their eyes to improve their tracking of fast-moving prey in deep, cold water, suggests a new study. Researchers already knew that certain large ocean predators – such as...

Jan 11, 2005 · We show here that warming the retina significantly improves temporal resolution, and hence the detection of rapid motion, in fast-swimming predatory fishes such as the swordfish.

In the swordfish (Xiph- ias gladius), a highly specialized heating system lo- cated in an extraocular muscle specifically warms the eyes and brain up to 10 C–15 C above ambient water temperatures [2, 5].

There is evidence to suggest that this flashing ultraviolet pattern created by a rapidly swimming swordfish will create confusion in a school, by breaking up the single bulky form of these magnificent predators. The swordfish, then, can play hide and seek to improve its hunting skills, becoming one of the most formidable of pelagic predators.

Jan 11, 2005 · The enhanced temporal resolution allowed by heated eyes provides warm-blooded and highly visual oceanic predators, such as swordfishes, tunas, and sharks, with a crucial advantage over their agile, cold-blooded prey.

Swordfish, the sole member of the Xiphiidae family, are easily recognizable by their long, flattened bill, resembling a sword. They have a stout body with large eyes. They have a tall, crescent-shaped first dorsal fin, followed by a smaller second, and similarly shaped anal fins.

Jan 10, 2005 · Zoologists have answered the intriguing question of why swordfish keep their eyes warm while the rest of the body remains resolutely cold-blooded: it's all the better to see their prey with.