Undulate Ray

The Undulate Ray (Raja undulata) is a distinctively patterned skate in the family Rajidae, named for the bold, wavy dark bands that cross its dorsal surface. It occurs in the northeastern Atlantic and Mediterranean, from the English Channel and western British Isles south along the coasts of Portugal, Spain, and West Africa. It favors relatively shallow, warmer waters compared to some related skate species and has a comparatively restricted, patchy distribution. Historically subject to significant fishing pressure as bycatch and in targeted fisheries, particularly in parts of the English Channel and Bay of Biscay, it is now considered Near Threatened, with management measures introduced in some areas to support recovery.

• Disc: rhomboid, with a moderately pointed snout
• Color: pale sandy to tan background crossed by bold, dark, wavy undulating bands, often with pale spots between the bands
• Thorns: small scattered thorns along the midline of the back and tail
• Underside: pale cream to white
• Size: typically 70-100 cm total length

The striking wavy banded pattern is diagnostic and readily distinguishes it from the mottled or blotched patterns of the thornback ray and other similarly sized skates.

Undulate Rays are found in the northeastern Atlantic from the western English Channel and southern British Isles south through the Bay of Biscay, along the Iberian Peninsula, and into the Mediterranean and eastern Atlantic waters off West Africa. They favor relatively shallow, warm-temperate coastal waters on sandy or rocky seabeds, typically at depths of less than 100 m, and are notably more restricted to shallower, warmer water than some other European skate species. Certain coastal areas, such as parts of the English Channel, support locally important concentrations of the species.

Undulate Rays are bottom-dwelling ambush predators that feed on crustaceans, small fish, and other invertebrates found over sandy and rocky substrates. They are relatively sedentary, often remaining within localized coastal areas rather than undertaking long migrations. Reproduction is oviparous, with females laying horn-shaped egg cases on the seabed that incubate for several months before hatching. Due to their patchy, coastally restricted distribution and historically high fishing pressure in certain regions, targeted management and monitoring efforts have been implemented in parts of their range to help stabilize populations.