The starfish, also known as sea star, is known for its five arms and spiny covering. It is an invertebrate – a creature devoid of a backbone. To date, about 1,600 starfish species are living in rocky shores, tidal pools, and coral reefs. While the starfish has armor-like skin and the ability to camouflage, it is often at the mercy of these 7 predators:
List of Starfish Predators
Sharks – the apex predators that they are – feast on whatever meat source they could attack in the water. Some feed on plankton, while some prey on mammals and larger fishes. At times, they eat on the slow-moving sea stars that live on the ocean bed.
Sharks prey on starfish in several ways. Basking sharks, one of the main predators of starfish, for example, utilize ram feeding. Suction feeding, on the other hand, is a practice observed by megamouth sharks. Wobbegongs and angel sharks, often found on the seabed, make use of camouflage first. Once they are undiscernible, they feast on their unknowing prey.
Because of the shark’s massive size, most of them find it easy to swallow the starfish whole.
2. Manta Ray
The manta ray is famous for its horn-shaped fins, giving them an ‘evil’ appearance. As such, manta rays also go by the moniker devilfish. A ‘cousin’ to the stingray, this creature is are often found in temperate and tropical waters.
The manta ray is a filter feeder, meaning it consumes suspended food sources in the water. Through this mechanism, it can consume krill, shrimps, and planktonic crabs. The manta ray can also be found lurking in the depths of the ocean, always on the lookout for fish, starfish, and other food sources.
Since the manta ray takes about a year to give birth to pups, the species is now considered vulnerable. The threats of pollution and overfishing have greatly reduced the manta ray population. With its gill rakers being used in Chinese medicine, the numbers of manta rays are expected to further decrease in the absence of conservation measures.
3. Sea Turtle
The marine turtle, which is found in almost all regions (except the poles), is one of the starfish’s bigger predators. One group, the leatherback sea turtle, can weigh as much as 1500 pounds. It can grow up to a whopping 9 feet in length as well.
A sea turtle that is on the lookout for starfish or other prey can spend anywhere from 5 to 40 minutes underwater.
Although this shelled reptile fancies sea stars, fishes, and worms, it eats plant sources as well. As an omnivore, the marine turtle can live on a diet of seaweed and seagrasses.
In fact, as sea turtles get older, they lean towards a more herbivorous diet. Fortunately for the starfish, a mature marine turtle is the least of its worries.
4. Red King Crab
The next predator of starfish that we are going to look at is Red King Crab. Of all the commercially harvested crustaceans, this shelled creature proves to be the biggest of all. As the ‘king’ of all king crabs, this species is often found in the Gulf of Alaska and the Bering Sea. The usual red king crab can weigh about 28 pounds, and grow a leg span of about 5.9 feet.
The red king crab has three pairs of walking legs. It also has a pair of claws that it uses for catching prey. The bigger claw is used to crush prey, while the smaller one is used for handling its food source.
Since red king crabs vary in size, their food preferences vary as well. The smaller ones dote on algae, small clams, and small worms. The bigger ones, on the other hand, predate on a variety of animals. Apart from the usual starfish, these larger crustaceans also eat fish, mussels, clams, worms, even barnacles.
Fun fact: despite its name, the fresh red king crab is actually burgundy in color. It only turns red when it is cooked.
5. Bony Fish
The bony fish belongs to the group Osteichthyes. As the name suggests, it has a skeleton made of bony tissue instead of the usual cartilage. To date, about 28,000 bony fishes are swimming in rivers, lakes, seas, and oceans.
Several bony fishes, such as the catfish, are bottom feeders. These species are the starfish’s main predator, given that the latter is often lodged on the sea bed. Some species, on the other hand, have large teeth that enable it to feed on shelled creatures.
The shrimp may be small, but it can feast on creatures bigger than it – just like the starfish. They are plentiful, as they exist in different types of habitats. This starfish predators can be found on seafloors, feasting on sea fishes and other prey on the bottom. They also thrive in lakes, rivers, estuaries, and coasts.
Known for its slender legs, long whiskers, and narrow muscular tails, the shrimp plays an integral role in the food chain.
The shrimp’s whiskers – also known as antennae – are actually useful for its feeding behavior. While the longer antenna can help orient itself to its surroundings, the shorter one can help it determine if its prey is suitable.
Some species, such as the pistol shrimp, let out a ‘sonic boom’ that can stun starfish and other food sources. The mantis shrimp, on the other hand, can deliver a punch that is strong enough to crack a clam open.
7. Sea Snail
We end our list of starfish predators with sea snails. The sea snail is mollusk known for having a durable external covering. Most shells usually have a coiled design, while the Julidae family has the characteristic bivalve-looking armor.
The sea snail ranges in size. Some only span a millimeter, while a certain species – the Syrinx aruanus – can grow to up to 91 centimeters. The bigger sea snails prove to be a formidable predator to starfish and other marine creatures.
While most sea snails scrape algae off rocks, there are some that feast on starfish and other shelled creatures. The sea snail can even drill a hole in shells, giving it unprecedented access to the food inside.
Despite its name, the starfish is not technically a fish. Although it has spiny armor, it is an easy catch for its bigger predators, such as the shark, manta ray, sea turtle, and bony fish. The sea snail and shrimp, despite their smaller size, can prey on starfish as well.
I hope that this article on starfish predators was helpful! If you are interested, visit the Animal Facts Page!