Fun Black Hagfish Facts For Kids | Kidadl


Fun Black Hagfish Facts For Kids

Arts & Crafts
Learn more
Reading & Writing
Learn more
Math & Logic
Learn more
Sports & Active
Learn more
Music & Dance
Learn more
Social & Community
Learn more
Mindful & Reflective
Learn more
Outdoor & Nature
Learn more
Read these Tokyo facts to learn all about the Japanese capital.

Hagfishes are slime-producing marine fish, often called slime eels because of their uncanny resemblance to eels. They belong to the Myxinidae family that consists of approximately 76 species of hagfish that dwell in deep cold sea waters around the world. These marine creatures are the only known animals who have a skull but lack a vertebral column. These fish have no jaws or are jawless, and are closely related to the sister group of jaw vertebrates. The current existing hagfish species look exactly like the ones that lived around 200-300 million years ago. This article is about a very strange and interesting marine creature belonging to the same family, and it will tell you everything you need to know about it including its range, distribution, habitat, diet, food items, life span, physical description, behavior, and even its ability to produce slime!

The black hagfish (Eptatretus deani) is similar to any other type of hagfish. It is in the genus of Eptatretus and is popular for its unusual diet, feeding habits, and slime producing capabilities. Despite its eel-shaped body, you must know that this species is not related to eels in any way and just bares a striking resemblance. It is commonly called the slime eel. It was first described and introduced as Eptatretus deani by American ichthyologists, Barton Warren Evermann and Edmund Lee Goldsborough in 1907. The physical and biological characteristics of this species are unique as it has four hearts, eight barbels near its mouth, a fairly large nostril, two parallel rows of pointy, thorn-like teeth, rudimentary eyes, 11-14 pairs of gill pores, and one gigantic head. This hagfish has poor vision but its other senses like touch and smell are highly developed which helps them navigate and even track their prey, even in some of the lowest depts of the ocean.

Similar to other hagfish, this species also hunts via trapping its prey in a knot, producing slime to suffocate them and enters their body to feed on their flesh and viscera within. Hagfish also search and feed on dead marine organisms or carcasses of fish found on the ocean floor. The hagfish distribution occurs in the North Pacific Ocean, Mexico, Central Baja, Canada, and southeastern Alaska. Is the black hagfish slime dangerous? Or are black hagfish toxic? Read on to find out!

Learn about some other fish from our channel catfish facts and meagre fish facts pages.

Fun Black Hagfish Facts For Kids

What do they prey on?

Smaller vertebrates, and dead creatures

What do they eat?


Average litter size?


How much do they weigh?

Up to 3 lb (1.4kg)

How long are they?

11.8-35 in (30-89 cm)

How tall are they?


What do they look like?

Jawless, black, and gray

Skin Type

Wet slimy skin

What were their main threats?

Large Predators

What is their conservation status?

Data Deficient

Where you'll find them?

Deep Sea, Marine Coral Reefs


Mexico, Southeastern Alaska, Eastern North Pacific Ocean









Black Hagfish Interesting Facts

What type of animal are black hagfish?

The black hagfish (Eptatretus deani), just like its name suggests, is a fish belonging to the Animalia kingdom, phylum Chordata, and is the genus of Eptatretus.

What class of animal do a black hagfish belong to?

This hagfish belongs to the Myxini class.

How many black hagfish are there in the world?

The accurate data of the population size of this species is unknown but the populations are said to be stable.

Where do a black hagfish live? 

The range of this species occupies the oceanic waters of the eastern and north Pacific Ocean, to southeastern Alaska, Central Baja California, Mexico, and some regions of Canada.

What is a black hagfish's habitat? 

These fish live in the mesopelagic and abyssal regions of the Pacific Ocean and are often found foraging for prey or in search of carcasses near the ocean floor. They prefer living in temperate waters and are found at a minimum depth of 338 ft (103 m), and a maximum depth of 8999 ft (2,743 m).

Who does black hagfish live with?

These fishes are solitary and live alone.

How long do a black hagfish live?

A hagfish has an average life span of 40 years in the ocean, and about 16-17 years in captivity or a protected environment such as an aquarium.

How do they reproduce?

Because they inhabit deep waters, information regarding black hagfish reproduction is limited. What we do know is the typical length of these fish when they reach sexual maturity is about 17 in (42 cm) in length. Adult mature females generally carry up to 40-42 eggs in divided groups that often vary in size. The average egg is around 0.1 in (0.5 cm) in length.

What is their conservation status?

The IUNC Red List of Threatened Species has classified the species as Data Deficient.

Black Hagfish Fun Facts

What do black hagfish look like?

300 million year old hagfish fossils revealed that these fishes have not undergone any significant evolutionary changes for over three centuries. Here are details about the black hagfish description, biology, and their physical characteristics.

They have a long, lean, uniform black-brown, eel-like body, giving them the common name slime eels. They have no true fins, but placed far back on its body is a single dorsal fin fold and a ventral fin fold placed towards the end. The caudal is fairly wide and displays ray-like patterns. This fish has no scales so its skin looks like a loosely fitting sock covering its body. These fish have no jaws, but several pairs of barbels, sensory tentacles close to their mouth, and a large nostril on the top of their head. Juveniles may display light spots and a faded prune color. They produce slime within their glands by drawing water in their intermediary filaments to create a sticky gel-like substance. This slime is gray-white, brown, or pale yellowish in color and is used as a defense mechanism against predators. When caught by a predator, they release large amounts of slime in the predator's gills, disabling their ability to respire and loosening their grip on the black hagfish to avoid suffocating. Since they are often confused with the Pacific hagfish, let's discuss Pacific hagfish vs black hagfish to learn the differences between them:

Unlike the black hagfish, Pacific hagfish have a uniform brown-red or blue-purple body, white ring or band-like patterns around their gill pores, and the caudal fin is not as round. Pacific hagfish also typically inhabit waters no deeper than 584-2,970 ft (18-900 m) and live in burrows occasionally.

* Please note that this image is of a sixgill hagfish from the same genus as the black hagfish. If you have an image of a black hagfish, please let us know at [email protected].

Discover fun facts about the black hagfish that produces slime to protect itself.

How cute are they?

Due to their bland appearance, slime production, and strange feeding habits many scientists and people, in general, have named the hagfish as one of the most disgusting sea creatures.

How do they communicate?

They communicate and navigate with the help of their sensory organs.

How big is a black hagfish? 

An adult female hagfish is typically 25 in (63 cm) in length, whereas males are typically 19 in (48 cm) in length. They are twice the size of a koi!

How fast can a black hagfish swim?

The accurate speed rate of a hagfish is unknown but, it generally swims slowly along the seafloor like a slithering snake with occasional bursts of speed.

How much does a black hagfish weigh?

Female hagfish weigh around 260 g (9 oz), whereas males are 180 g (6 oz).

What are the male and female names of the species?

This species does not have sex-specific names for its members and are simply called males and females.

What would you call a baby black hagfish?

A baby hagfish is called a larva.

What do they eat? 

As this fish lacks jaws, it depends on its highly developed senses of smell and touch to navigate and find food. Their feeding behavior is quite vigorous as it tends to capture its prey by creating a knot using its own body, and then pulls itself out through the knot. The released slime is meant to clog the prey's gills, that would otherwise suffocate it. They also often try and enter inside weak large fish through their mouth to feed on their viscera. Their diet includes a variety of marine animals such as polychaete worms, shrimp, hermit crabs, brittle stars, and bony fishes.

We know what you're thinking, their eating habits are disgusting and gross! However, this fish helps keep the seafloor clean by consuming dead creatures off it. They also serve as a food source for predators like larger fish, seabirds, and seals that are difficult to entrap in the slime.

Are they dangerous?

So far no events have been reported where a hagfish has inflicted serious damage to a human. Some say hagfish can potentially kill humans, while others disagree. Attacks on humans are rare, but they do occur. There is no harm in being careful around them.

Would they make a good pet?

Even though they are found at a minimum depth of 337 ft (103 m), these organisms have not been researched enough. Therefore, we do not recommend them as pets cause there are too many unknowns.

Did you know...

Hagfish have a well-developed network of capillaries in their skin that might allow them to breathe through their skin when buried in mud.

Recent studies in molecular biology and evolution have shown that hagfish slime has similar properties to spider silk. If hagfish slime is produced in laboratories, it could replace artificial materials like nylon in clothing. This would ultimately be better for the environment as nylon is produced from petroleum.

Polistotrema deani is the other black hagfish scientific name also given by Evermann and Goldsborough in 1907.

Are black hagfish endangered?

No, their population size is currently stable.

What are the characteristics of a black hagfish?

The most distinctive characteristic is that these hagfish produce large amounts of slime as a defense mechanism. The slime comprises mature thread cells that are coiled and thread-like and extend up to 4 in (10 cm).

Here at Kidadl, we have carefully created lots of interesting family-friendly animal facts for everyone to discover! Learn more about some other fish from our African lungfish facts or white tuna facts pages.

You can even occupy yourself at home by coloring in our free printable black hagfish coloring pages.

Written By
Mellisa Nair

<p>Specializing in the creation of SEO-friendly content, Mellisa brings enthusiasm and expertise to our team. Her work in digital marketing and social media is complemented by her academic background in economics and English literature, as she holds a Bachelor's degree in these subjects from Wilson College Chowpatty, Mumbai. Mellisa's experience working with clients from various industries, including retail, education, and technology, reflects her ability to adapt her skills to different contexts and audiences.</p>

Read The Disclaimer

Was this article helpful?