Elephant Fish

The elephant fish, also known as the Australian ghost shark, is a unique-looking fish with an elongated, protruding snout. It commonly feeds on mollusks or other invertebrates on the ocean floor of the South Pacific Ocean. It is a commonly eaten seafood in New Zealand, where it is sometimes used for fish and chips.

5 Incredible Elephant Fish Facts

• The elephant fish has no bones; instead, its skeletal structure is entirely cartilage.
• These fish have a special reflective tissue in their eyes, so their eyes can appear to transition between shades of yellow and green.
• It can be aggressive and fight back hard if threatened.
• These fish are very popular in cooking, particularly in New Zealand. They are common in fish and chips!
• Elephant fish females are usually larger than males.

Scientific Name

The scientific name of elephant fish is Callorhinchus milii. Their genus name, Callorhinchus, is from the Greek words “kalo” meaning beautiful, and  “rhyngchos,” meaning snout. Zoologist Bory de Saint-Vincent first coined the name in 1823. 

Appearance

It is quite a unique-looking bottom-feeding fish. Their most prominent feature is their extended snout. Elephant fish are about 2 to 4 feet in length. That’s the average height of a 3 to 6-year-old toddler! Once fully mature, they weigh about 10 to 15 lbs, but larger fish can even get as heavy as 20lbs if they have a rich diet. Their body is almost entirely scaleless and are generally a mixture of blue, black, or brown colors.

These are some of the most recognizable fish due to their outwardly extended snout. They have two dorsal fins, one near their head and one in the middle of their back. The dorsal fin in the middle of their back has a long spine that they use to defend themselves. Their spine contains small amounts of venom, but it is likely not enough to harm humans.

Their eyes are high on their heads and are a yellow-green color. Elephant fish also have large, flat teeth, which are an adaptation that helps them consume their prey from the bottom of the ocean.

Behavior

Elephant fish are solitary animals. They only pair up when breeding. They spend most of their time scouring the bottom of the ocean, feeding on the muddy and sandy seafloor. They filter feed, so their body automatically filters out the mud and sand while they consume the creatures living on the ocean floor.

Habitat

They are demersal fish, meaning they live near the sea bed. They dive very deep into the ocean, thriving at depths of 600 to 5,000 ft below the surface. They are found in the South Pacific Ocean and Tasmanian Sea, in and around Australia and New Zealand.

Diet

They are carnivorous fish, meaning that they eat only other animals. As bottom feeders, they will eat almost any invertebrate in their path, including small octopuses, squid, worms, crustaceans, starfish, brittle stars, shrimp, sea cucumbers, and sea urchins. They can detect electrical currents in the water, which helps them seek out prey and find mates.

What Does the Elephant Fish Eat?

The diet of this fish is based on small, soft invertebrate animals that live on the ocean floor, like octopuses, mollusks, shrimp, and shellfish. They cannot eat bony fish because their teeth and digestive system don’t allow it.

Predators and Threats

It is often preyed on by larger fish, such as sharks. Humans also commonly fish for elephant fish. Since they are boneless, they are used in cooking quite often. Currently, elephant fish are managed through fisheries regulations in Australia and New Zealand, and the species is listed as Least Concern by the IUCN. However, monitoring continues to ensure populations remain stable.

What Eats the Elephant Fish?

Elephant fish are quite large, but they still have many predators. Larger fish, such as hammerhead sharks, tiger sharks, and great white sharks, will often eat them.

Reproduction

They are oviparous. In other words, they lay eggs. These fish usually mate in the spring and early summer (from October to January in the southern hemisphere). When mating, the males and females rise from the bottom of the sea to shallower waters. Elephant fish will locate mates using their ability to follow electrical fields.

The males have claspers that allow them to transfer their sperm to the female. The female then goes to even shallower waters to lay the eggs. Their keratinous eggs are then released onto the sandy ocean floor. At the beginning of the incubation period, the eggs are yellow in color, then they become brown, and they turn black right before they hatch. The egg incubation period is usually around 8 months, and the embryo feeds on the egg’s interior for nourishment.

Elephant fish males usually mature at around 3 years of age. The females mature slightly later at 4 to 5 years of age.

Elephant Fish Babies

Once hatched, the baby elephant fish are around 2 to 6 inches in length, depending on the nutrition they receive during their incubation. Their babies are known as pups. The egg case of these pups has a horny edge on one end, the end they crawl out of when they hatch. They usually hatch between October and November. Their leathery egg capsule then washes ashore after these pups have left their eggs.

The pups will stay in shallow waters for the first few weeks before they swim deeper into the ocean. They are completely independent when hatched and do not spend any time with their parents.

Lifespan

Elephant fish live an average of 10 years, but in some cases, they have been known to live as long as 15 years. As they begin to age, they become more susceptible to ailments. Some of these include:

• Epitheliocytosis: a condition of the skin and gills and fish due to a bacterial infection.
• Parasites: parasites might begin to feed under the fish’s gills, causing damage to the scales. 
• Columnaris: A disease that causes lesions on the fish’s back and belly. This is usually caused by the water being dirty or if the fish is malnourished.
• Fungal infections

Population

The exact number of this fish in the world is unknown. Elephant fish populations are currently stable and actively managed through fisheries regulations. The species is listed as Least Concern by the IUCN, but continued monitoring is important to ensure sustainability.