Do Dinosaurs like eating fish?

In this post, we will discuss Dinosaur eating fish and get to know about the dinosaurs that have a diet based on fish, we will also talk about the life of these animals and their ecology.

Do Dinosaurs like eating fish?

Dinosaurs that have a diet based on fish are the ones of the genera Baryonyx and Spinosaurus. Both genera belong to the same family, Spinosauridae and have several characteristics in common.

The first vertebrates to appear on Earth were fish, more than 500 million years ago, in the Cambrian period. They are, in evolutionary terms, the ancestors of all animals with a backbone.

With this early appearance, fish have always been the basis of food for many animals, including dinosaurs. Some dinosaurs had their diet entirely based on fish, which makes an excellent and vast source of protein for these amazing animals.

First, what is a dinosaur?

Dinosaurs were large animals that dominated the Earth during the Mesozoic Era. The word Dinosaur has a Greek origin and means “terrible reptile”, the biological name of the Dinosauria group was made by the English palaeontologist and anatomist Richard Owen, in 1842.

The origin of birds has been a controversial topic within evolutionary biology for many years. More recently a scientific consensus has emerged, birds are a group of theropod dinosaurs that evolved in the Mesozoic Era. In the phylogeny sense, birds have evolved from dinosaurs.

They were terrestrial. According to this definition, pterosaurs, the dinosaurs’ contemporary flying reptiles, and plesiosaurs, the aquatic reptiles that dominated the seas of Europe, are excluded. Only land animals are considered dinosaurs.

The evolution of dinosaurs quickly determined the characteristics of the new group, at the time they populated the Earth, they were the largest existing animals. Sauropods, one of the dinosaur groups, for example, represented the largest animals that lived on the planet so far.

The dinosaur superorder is divided into two other orders which differentiate, among other anatomical features, by the structure of the pelvis. The taxonomy of this group is still debated among scientists. 

In turn, dinosaurs were divided into six groups: Theropods, Earth’s biggest predators; Sauropods, as mentioned above, the largest animals that ever lived on the planet; Keratopsids, with head ornaments; Stegosaurus, with plaques on the back; Ankylosaurus, with a “shield” and “club” on the tail; and Ornithopods, called duckbill dinosaurs.

Dinosaurs that feed on fish

It is believed that many dinosaurs had fish as a source of protein and energy, but among these different animals, it is worth mentioning two that are well known and have almost strictly fish in their diet. These dinosaurs are members of the Baryonyx and Spinosaurusgenera. Both belong to the Spinosauridae family and have several characteristics in common.

·      Spinosaurus Stromer, 1915

·      Baryonyx Charig & Milner, 1986


Spinosaurus lived between 95 and 100 million years ago, in the period known as the Cretaceous. At that time, the seas were already inhabited by reptiles such as Ichthyosaursand Plesiosaurs, which belong to a different group from the dinosaurs that inhabited the land. This is the first dinosaur known to science that could inhabit, even partially, the aquatic environment.

The discussion that some Spinosaurus would be semiaquatic has been around for some years among palaeontologists, but the concept was challenged by anatomical, biomechanical, and taxonomic issues that remained unknown. The uncovered tail sheds new light on how this giant managed to get around in the water.

Spinosaurus fed on fish. This animal had the traditional characteristics of other predators, except for the teeth that were straight and not curved, and the slightly larger arms, probably used for swimming.

Spinosaurus was a fisher dinosaur, as indicated by his elongated jaws, tapered teeth and raised nostrils. When a Spinosaurus’ tooth was found in the remains of a Pterosaur, it was suggested that the Spinosaurus would be a widespread and opportunistic predator. Resembling large polar bears, basing most of their diet on fishing.

Another intriguing fact is that they are orifices present at the tip of the Spinosaurus’ snout that were probably connected to the animal’s brain, just like the crocodiles of today, which guarantees the Spinosaurus efficiency in hunting in rivers and lakes.

Palaeontologists discovered a Spinosaurus fossil in Morocco in 2014, it showed that they had adaptations to spending a lot of time underwater and so could catch the huge Cretaceous fish and also go ashore to hunt other dinosaurs. With this discovery, it became clear that Spinosaurus alternated between hunting environments, in the water competing with huge crocodilians and on land competing with other huge theropods.

Since their discovery in 1912, dorsal vertebrae have attracted more attention, as they were different from those of other theropods. The long vertebrae with their elongated neural spines led to the name Spinosaurus, coming from the Latin, meaning “Lizard Thorn”, with the various elongated vertebrae arranged vertically on the back and covered with skin that forms candle-shaped structures.  

The teeth found, 20 in total, were smooth, conical and did not have saws as in tyrannosauridae or carcharodontosauridae. In addition, they were thinner and rounded, something unusual in a predatory dinosaur. Early fossils did not give an accurate idea of ​​the shape of the animal’s skull, so early illustrations of it showed it with a short skull similar to that of other theropods, and so it was reconstructed for many years.

After new Spinosaurus were found and some additional fossils emerged, our view of its skull changed. We came to see him with an elongated crocodile-like skull. Until now, we believed that its body structure should be similar to that of other theropods, with the difference of the elongated skull and dorsal region. Spinosaurus was always portrayed with long legs adapted for walking on dry land, long arms to hold prey, whether dinosaurs or fish. We imagined Spinosaurus walking on dry land most of the time and occasionally standing at the edge of a lake or river, or even with its legs in shallow water, looking for careless fish.

Spinosaurus was featured as the main antagonist in the movie Jurassic Park III. In the movie, the Sipinosaurs were exhibited as bigger and more dominant than a Tyrannosaurus. In reality, Spinosaurus and Tyrannosaurus lived in different places, separated by the Atlantic Ocean and the Caribbean Sea. Tyrannosaurus rex lived in North America and the Spinosaurus lived in North Africa. In addition, they did not exist at the same time, Spinosaurus is a little older.


Baryonyx was a species of carnivorous, semi-bipedal dinosaur that lived during the Cretaceous period. It measured about 9 metres in length, 3 metres in height and weighed around 1.5 tons. Baryonyx was a close relative of Spinosaurus, the two are often confused by having similar snouts and by Barionyx appearing to have an almost similar crest to Spinosaurus.

Baryonyx lived in Europe and was discovered in England in 1983 by William Walker. It was a carnivore and probably fed on fish – since scales and bones of fossilized fish were found in its stomach. 

Despite being considered a theropod, it possessed several features unusual to its suborder, such as teeth similar to those of today’s crocodiles and alligators, as well as a claw measuring about a foot in each hand.

In addition to fish scales found in an individual’s stomach, the remains of a young Iguanodonhave also been found in it. With that, the scientists deduced that it was also an opportunistic predator, able to use its power to hunt other dinosaurs. 

The characteristics of their snout and teeth similar to current crocodilians, lead to believe that these animals used aquatic environments as hunting grounds.

This dinosaur has appeared in several documentaries about the life of these giants on earth millions of years ago. Lately, in 2018, it appeared in the movie Jurassic World – the Fallen Kingdom in a chase scene to the protagonists.


In this post, we discussed Dinosaur eating fish and learnt about the dinosaurs that have a diet based on fish, we also talked about the life of these animals and their ecology.

If you have any thoughts or doubts, feel free to drop us in a comment below!

Frequently Asked Questions (FAQs): Dinosaur eating fish

Which dinosaur does eat fish?

Millions of years ago Spinosaurus and Baryonyx probably based their diets on fish and other river creatures.

How big could a dinosaur be?

Dinosaurs could reach 20 years of age with a height of 3.6 to 3.9 metres from the ground to the hips. The length from nose to tail reached approximately 13 metres, and the weight was between 5.5 and 8 tons. The rate of growth was fast: they gained 3 kilograms a day for 13 years

How do scientists know what dinosaurs ate?

Some fossilization processes were so perfect that it was even possible to identify the presence of stomach contents, such as scales, bones and stones. It is also possible to cite that some dinosaurs were found with bite marks compatible with predators such as Tyrannosaurus on their bodies.

What did carnivorous dinosaurs eat?

As is the case with today’s carnivorous animals, dinosaurs belonging to the theropod group fed on other dinosaurs, small animals, fish, or insects.

How do you know the skin colour of dinosaurs?

Using microscopy techniques on fossil feathers, it is possible to see where melanosomes (cellular structures responsible for pigmentation) have accumulated. So they found patterns in the feathers, like stripes and different colours.


Farlow, J. O., & Holtz, T. R. (2002). The fossil record of predation in dinosaurs. The Paleontological Society Papers, 8, 251-266. 

Barrett, P. M., & Rayfield, E. J. (2006). Ecological and evolutionary implications of dinosaur feeding behaviour. Trends in Ecology & Evolution, 21(4), 217-224.

Brusatte, S. L., Butler, R. J., Barrett, P. M., Carrano, M. T., Evans, D. C., Lloyd, G. T., … & Williamson, T. E. (2015). The extinction of the dinosaurs. Biological Reviews, 90(2), 628-642.

Buffetaut, E. (1989). New remains of the enigmatic dinosaur Spinosaurus from the Cretaceous of Morocco and the affinities between Spinosaurus and Baryonyx. Neues Jahrbuch für Geologie und Paläontologie-Monatshefte, 79-87.