14 Interesting Facts About Remora

Remoras and Their Symbiotic Relationships

Remoras are a family of tropical and subtropical marine fish known for their ability to attach themselves to larger marine animals using a suction disk on top of their heads. This allows them to essentially “hitch a ride” on animals like sharks, whales, turtles, and manta rays. This relationship is symbiotic, meaning both the remora and host animal benefit. The remora gets free transportation, protection from predators, and access to the host’s food scraps and parasites on which to feed. Meanwhile, the host animal gets cleaned of those parasites and debris that could otherwise cause infection or drag.

Remoras have fascinated people since ancient times, with their perceived ability to slow down ships leading to their name, which means “to delay” in Latin. Today, remoras continue to intrigue biologists studying the nature of symbiotic relationships. While remoras occasionally attach to divers or boats by accident, they inevitably detach and search for another marine host to meet their needs. Their unique mode of transportation allows remoras to conserve energy while accessing food sources they could not reach on their own, making them highly successful in tropical oceans around the globe.

Remoras are a fascinating group of fish with some unique adaptations and behaviors. Here are 14 interesting facts about these opportunistic hitchhikers of the sea:

Interesting Facts About Remora

1. Remoras use a large suction disk on top of their heads to attach themselves to larger marine animals. This modified dorsal fin allows them to securely “hitch a ride” with sharks, whales, sea turtles and more. It creates strong suction thanks to a combination of suction cups and sticky mucus.
2. They are excellent hitchhikers that can travel long distances. By latching onto whales, sea turtles and other migrating marine life, remoras can traverse vast stretches of ocean without actively swimming themselves. Some have even been spotted clinging to ships!
3. Remoras feed primarily on host leftovers and parasites. They use their hosts as dining tables, feasting on scraps left over from the host’s meals. They also eat parasites on the host’s skin. This helps keep the host clean.
4. They rarely harm their hosts. There is no evidence of remoras inflicting damage on the animals they attach to. Occasionally they may feed on host mucus or tissue. Their advantages as cleaner fish outweigh any small annoyances.
5. Their hosts include sharks, marine mammals and sea turtles. Some favorites include sharks like great whites, hammerheads and whale sharks, as well as manta rays, sea turtles, whales and large bony fishes. Any large marine animal is potential real estate!
6. Remora sucking power has been measured at 25-40 pounds per square inch. Their suction ability is greater than many commercial suction cups. Specialized connective tissue helps them hang on even when hosts make sudden speed changes.
7. They can swim backwards while staying attached to a host. Using specialized fin movements, remoras can travel backwards along a host animal while maintaining their suction grip. This allows them to reposition themselves.
8. Remoras spawn near their hosts. To give their eggs and offspring the best chance, remoras release gametes into open water in the vicinity of their host animals. This allows the next generation to find hosts from birth.
9. They exhibit varying degrees of host specificity. Some remora species latch onto a wide variety of marine life while others preferentially stick to certain hosts, like sharks or sea turtles. This may relate to differences in habitat range.
10. Fishermen use remoras to catch turtles and large fish. By attaching a fishing line to a remora’s body, fishermen release them to find targets and latch on. The fishing line allows the fishermen to then reel in prized catches.
11. Remoras have been used in scientific research. Their unique hitchhiking abilities have been used to attach tracking devices and cameras to marine animals. This allows researchers to monitor the movement, behavior and habitat use of typically hard-to-study ocean giants.
12. Fossil records show they have changed little in 18 million years. Remora fossils dating back to the Miocene epoch closely resemble modern-day specimens. Evolutionary speaking, they found an effective body plan early on and stuck with it!
13. There are 8 living species divided among two families. The 8 remora species comprise two families – Echeneidae (6 species) and Remorinae (2 species). They occupy warm waters worldwide.
14. Most remora species are not at risk of extinction. Due to their broad distributions and lack of fishing pressure, most remoras have stable populations. One exception is the whitefin sharksucker which has an uncertain conservation status.

In conclusion, remoras are fascinating creatures with unique adaptations and behaviors. From their suction-cup-like dorsal fin to their symbiotic relationship with larger marine animals, remoras have evolved to thrive in their aquatic habitats. They serve as a testament to the incredible diversity and ingenuity found in the animal kingdom.