Sharks are one of the most feared fish species in the wild aquatic world.
However, remora is a unique fish that attaches to sharks for survival without fear.
So let’s learn more about this fish and how it helps itself as well as the sharks. But first, let’s talk about remoras.
Interesting Facts About Remoras
Remora, also called suckerfish or sharksucker, belongs to the Echeneidae family.
All 8 species of these fish are famous for attaching themselves to sharks, whales, manta rays, other large marine animals, and even oceangoing ships.
Remoras primarily inhabit the tropical and temperate seas and oceans.
They can be found both in coastal regions as well as far offshore.
Depending on the species, their size varies between 30 to 90 cm (11.8 to 35.4 inches) in length.
The live sharksucker or the slender suckerfish is the longest species of remora fish, growing up to 110 cm (43.3 inches) in length.
In contrast, the white suckerfish or the white remora is the shortest species that grows only up to 30 cm as adults.
These fish are brown in color and have thin, elongated bodies. They have small cycloid scales on their bodies.
Remoras are famous for their suction cup at the top of their head that they use to attach to other creatures in the ocean.
They usually feed on the leftover of their host’s meals.
Remoras also act as cleaners by consuming the tiny parasites on the host’s skin.
Why Do Remoras Attach To Sharks?
Remoras are called ocean hitchhikers as they spend most of their lives attached physically to host fish such as sharks, other larger fish species, and sea creatures.
Remoras attach to sharks for their own benefit.
They’re tiny fish, and the chances of them getting predated by large fish are high in the ocean.
They attach themselves to sharks to feel secure. Most of the fish usually don’t go closer to sharks.
Hence, remoras get protected from potential predators.
Another advantage for remoras to attach to sharks is that they get free transportation across the ocean.
Remoras don’t need to spend their energy traveling across large oceans. Besides, their chances of meeting mates are also higher.
Remoras also get to feed on the leftover scraps of food that sharks drop off from their mouth.
They don’t have to hunt or search for food while attached to sharks.
Alright! Now that you know why remoras attach to sharks, you must be wondering how they do this exactly?
How Do Remoras Attach To Sharks?
The most distinguishing feature of remoras is the suction cup attached to their head.
This flat oval sucking disc helps them attach to sharks, usually on their belly or underside.
The suction plate is a specialized dorsal fin that has become a disc covered with connective tissue that seals it to the sharks.
The round disc on a remora’s head contains flexible membranes to maintain suction.
The sucking disc is developed from a modified spinous dorsal fin with 16 to 20 movable laminae.
These laminae help create a partial vacuum to achieve suction capabilities for attaching to sharks.
Also, the suction discs that remoras have on their head have elastic collagen fibers, enabling them to have maximum surface contact with the fish it’s getting attached to.
Adult remoras have developed suction cups on their heads, so they easily attach to sharks.
In contrast, baby remoras aren’t born with fully formed suction cups on their heads.
Therefore, it’s difficult for them to attach to sharks until they grow up.
These fish can attach to sharks only once they grow up, and the suction cups develop into full size to gain adhesive quality on their heads.
The three typical fin elements, fin spines, distal radials, and the proximal, middle radials, undergo a series of small changes as the baby remora develops to form its sucker.
How Do Sharks Benefit From Remoras?
The shark and remora relationship benefits both species. Remoras travel everywhere the shark goes without troubling it.
They simply attach to the sharks and hitch a ride.
Remoras benefit the sharks by eating the parasites accumulated on their skin and mouth, which may otherwise irritate and harm the sharks.
Consuming the parasites helps to keep the sharks clean and healthy.
Remoras also help keep the water around the sharks clear by preventing the development of unhealthy and dangerous organisms around them.
Do Sharks Eat Remoras?
Sharks and remoras share a symbiotic relationship where both benefit from each other.
Studies have shown that sharks understand the benefits of having remoras attached to them.
They have also been observed slowing down and risking their life to allow remoras to attach themselves.
While most shark species appreciate remoras, not all are happy with this relationship.
Sandbar and lemon sharks have been documented acting aggressively against the remoras.
They have even consumed the beneficial remoras.
Despite these rare instances, the shark and remora relationship is still considered one of the best examples of mutualism in nature and is likely to continue for millions of years.