Sunfish are some of the strangest looking fish species in the world.  They have flattened bodies with a very strange tail fin.   This fish is also called the common mola or the mola and is one of the heaviest bony fishes in the world.  An adult sunfish can weigh 247 – 1000 kg. The biggest sunfish ever caught a weighted 1600kg and was caught in 1910.

The chances that you saw one of these fish species is pretty slim since they are not held in too many aquariums because they do require lots of special care. They can live up to 10 years in captivity and they can grow rapidly if they eat the right foods.

What Do Sunfish Eat?

Sunfish are predatory animals.  They will hunt and kill a variety of aquatic species despite that they are not very fast.  Here is a quick look at the main foods that these fish species love to eat.

Jellyfish

In the past, people believed that they primarily fed on jellyfish.  Recent studies did however show that sunfish only consume about 15% jellyfish.  They do eat jellyfish but this is hardly their primary food.  Jellyfish is not nutritious enough to support the sunfish and this food source.  In aquariums, sunfish are not fed jellyfish too often because jellyfish can infect these rare fish species with parasites.

Small fish

Sunfish mostly prey on small fish species.  They will catch and eat just about any small fish species they find in their natural habitat.  They don’t have huge mouths and as such focus on fish species that are small enough to swallow whole.

Fish larvae

Sunfish and especially young sunfish, love to eat fish larvae.  These tiny animals are easy to consume because the Mola can suck them into their mouths quickly and fish larvae are small enough to feed even the tiniest of sunfish.   They will eat any type of fish larvae they can find.

Squid

Mola fish love to eat squid.  In aquariums, they are primarily fed on squid because squid contains lots of nutrients to help keep them healthy.  Squid are also boneless fish species which makes them easy to suck up and swallow whole.

Crustaceans

Mola fish or sunfish also enjoy eating a variety of small crustaceans.  They avoid larger crustaceans but can eat small and especially young crustaceans whose shells are still soft.  Crustaceans like crabs, lobsters, crayfish, shrimps, prawns, krill, and many others are good sources of protein for these majestic fish species.

Salps

Sunfish also catch and eat salps.  Salps are barrel-shaped planktic tunicate that has a gelatin-like body.  They are not very nutritious but these foods do still help the Mola by offering some nutrients and oils.

Eelgrass

While Mola is lingering about the ocean bottom, they might occasionally feed on pieces of eelgrass.  This type of plant usually grows in areas with sandy or muddy bottoms.  This is the only plant-based food that the sunfish will consume and they only consume these foods when other food sources are scarce.

Diet Variations

Sunfish are a rare find and they haven’t been studied in their natural environment for too long.  There probably is a lot of things we do not yet know about the diets of this strange fish species.  We do now know much more about them than we did a few years ago but more research is still needed to fully understand the care requirements for this cold-water fish.

How to Feed Sunfish

Sunfish are not kept in aquariums because they are challenging to care for.  They are also not very common and even though they are found in oceans across the world, they are still a rare sight to behold.   When these animals feed, they prefer to sneak up on their prey and suck food into their tiny mouths.  They usually focus on foods that are much smaller than their mouths so they can easily swallow and digest these foods.

What Do Sunfish Eat In The Wild?

In the wild, sunfish will hunt a variety of foods they find in their natural habitat.  They mostly eat small fish and fish larvae but also hunt for other foods such as squid, crustaceans, jellyfish, salps, and many others.

What Do Sunfish Eat In Captivity?

There are not many aquariums that keep sunfish.  In aquariums, they are mainly fed on squid since this is a very nutritious meal.  They may also be fed on other foods such as small fish.  Marine biologists do however avoid feed them on jellyfish since these jellies often cause the spread of bacteria.

What Do Baby Sunfish Eat?

Baby sunfish look much different from adult ones.  They have a lot of processing spines that almost make them look like some form of starfish.  These spines do eventually disappear.  Sunfish fry grows rapidly.  They can grow from 26 – 400kg, or up to 1.8m high in just 15 months.

As a small fry, they will eat on smaller prey such as fish larvae, crustaceans, and zooplankton.  As they grow bigger, they will start to feed on bigger foods.

Do Sunfish Bite?

Sunfish are not harmful to humans at all and won’t bite them.  They do not bite and their mouths are tiny which means even if they did bite, they wouldn’t cause much damage at all.  The only documented case of a sunfish injuring a human was when one of these fish species leaped onto a boat and caused injuries to a 4-year-old boy when it landed on the boy.

Do Humans Eat Sunfish?

This rare fish species is considered a delicacy in some regions of the world such as Taiwan and Japan.  In some areas, the fish is used in cuisine, and in other regions, they are used to manufacture traditional medicines.  It is however forbidden to catch this fish species in various part of the world such as the European Union because this fish species do contain toxins that can be harmful if consumed.