Common Remora

The common remora (Remora remora), a pelagic marine species belonging to the family Echeneidae, exhibits a specialized dorsal fin equipped with 22 to 26 soft rays, functioning as an effective suction apparatus. This adaptation enables the remora to attach itself to larger marine animals, such as whales, dolphins, sharks, and sea turtles, by creating a vacuum.

Characterized by a dorsal fin resembling a sucker and accompanied by an anal fin, the common remora displays a coloration that ranges from brown to black or grey. Individuals of this species can achieve a total length of up to 86.4 cm (34.0 inches), although the majority typically measure less than 40 cm (16 inches). The maximum recorded weight for the common remora is approximately 1.1 kg (2.4 lbs).

Remora remora engages in a symbiotic relationship with its host, wherein it generally does not inflict harm. The host facilitates the remora's respiration through fast-moving water, offers a continuous supply of food, provides transportation, and ensures protection. In return, the remora contributes to its host by consuming some parasites, although it may increase hydrodynamic drag. The remora can maintain its attachment to a single host for a duration of up to three months, with the capacity to relocate its position if threatened. Importantly, the common remora is unable to survive in stagnant water; a constant water flow over its gills is essential for breathing.

Predominantly inhabiting warm marine environments, this remora species has been observed in regions such as the western Mediterranean, the Atlantic Ocean, and the North Sea.

Instances of host fidelity are noted, wherein mating pairs may attach to the same host. However, the precise timing of spawning and comprehensive details of the species' reproductive behavior remain uncertain.

The diet of the common remora includes food scraps from its host, plankton, and parasitic copepods.

There are no known adverse effects on humans attributed to this species. Occasionally, remoras are inadvertently captured as bycatch and subsequently kept in aquaria. Historically, remoras have been utilized in unique fishing practices—attaching a fishing line to the remora, allowing it to adhere to a larger fish.

The common remora is also recognized by various other names, including suck fish, stout sucking fish, common sucker, shark-sucker, brown sucker, and shark pilot.