Let’s take a look at some rays! Manta Ray vs Stingray vs Eagle Rays. Much like siblings, they may be related but are actually pretty different in many ways.
Growing up and learning how to scuba dive in the Midwest, I will never forget my first ocean dive. The crystal-clear, warm water of the Caribbean made it easy to enjoy a shipwreck, more fish than I could count, and a majestic ray all in the span of thirty minutes. When I got out of the water, gushing about my dive, one of the instructors asked me if the ray I saw was a stingray, a manta ray, or an eagle ray. I sheepishly admitted that I had no idea, and after some research I learned that the ray I saw was a spotted eagle ray. That day began a never-ending journey for me to work on improving my reef creature ID skills.
Read More: Q&A with Marine Science Teacher, Anna Ortega
Rays can be easy to confuse, but here are some differences that may help you determine which is which.
Table of contents
- Differences between a Manta Ray vs Stingray vs Eagle Rays
- Size of Manta ray vs Stingray vs Eagle Ray
- Distinctive Features of Rays
- Tails of Rays
- Diets of Manta Rays vs Stingray vs Eagle Rays
- Lifespan of Rays
- Are Rays Dangerous?
- How to Identify Which Ray?
- Threats to Manta Rays, Eagle Rays and Stingrays
Differences between a Manta Ray vs Stingray vs Eagle Rays
First, what are rays?
In science, fish are separated into those with skeletons of bone, and those with skeletons of cartilage. Cartilage is what makes up our earlobe or the tip of our nose, and it helps these animals be both tough and flexible.
There are about 600 species of rays, which includes everything from ocean-crossing manta rays to stingrays that prefer to spend their time hiding in the sand. Rays have flat bodies that they move by flapping or rippling their pectoral fins. They have a slender tail, which in some species is paired with a venomous spine.
Some species live on the seafloor and hunt for their meals, but some traverse the open ocean and eat plankton from just below the surface. Rays are an important part of the ocean food web, and without them sharks and orcas could go hungry, and little invertebrate populations like crabs and oysters could explode.
So, can we tell them apart, and how?
Size of Manta ray vs Stingray vs Eagle Ray
Manta rays are the biggest of the rays. Adults can range from reef mantas with a 3.5 m (11 ft) wingspan, to giant oceanic manta rays with a 7 m (23 ft) wingspan! Oceanic manta rays can reach 3,000 kg (6,600 lb), and yet they glide through the water most gracefully.
The size of eagle rays is dependent on species, with an average at about 2.8 m (9 ft).
Stingray sizes varies greatly by species, but the average is around 1 m (3 ft). Equally important are the massive (2.2 ft wingspan) short-tail stingray and the tiny (10 cm wingspan) snort-nose electric ray.
Distinctive Features of Rays
The bodies of all kinds of rays are diamond-shaped, and they move using their pectoral (side) fins, but they do have a few differences that may help you decide which is which.
Manta Ray Features
Manta rays are the biggest, and they move by flapping their triangular fins like wings. The easiest way to recognize a manta ray is by their cephalic fins, horn shaped fins on either side of their mouth. These fins are used to guide plankton into their mouths while they feed. Manta rays also have prominent gills on their underside.
Eagle Ray Features
Eagle rays have very distinct snouts, which come to a point and make their mouths look almost like the beak of a bird. They need a snout to help them dig through the sand to feed. Eagle rays range from brown in color to elaborate patterns like the spotted eagle ray, or the ornate eagle ray.
Stingrays have the roundest body, but it is still diamond-shaped. Stingrays are often found lying or swimming along the bottom. Unlike manta and eagle rays who flap their fins like birds to move, stingrays ripple their pectoral fins to swim along. And because it’s in their name – stingrays can be recognized by their tails. They have the shortest tail of the three kinds of rays, a tail that starts out thick and then tapers off, concealing a venomous barb (or sting) they use for defense.
Tails of Rays
Manta rays have long tails with no spines or barbs on them. They use their size and speed to evade predators instead of having a defense mechanism like the eagle rays and stingrays.
Eagle rays have 2-6 venomous spines that start behind their dorsal fin, right at the start of their tail. They use these spines in self-defense, when they can’t swim away fast enough from predators.
Stingrays are names for their venomous barb, a last resort self-defense mechanism that sticks out halfway down their tail. They don’t use these barbs for feeding, only to protect themselves from predators. They can regrow this spine if they have to use it on a predator, but it takes a long time to regrow.
Diets of Manta Rays vs Stingray vs Eagle Rays
The diet of rays depends on where they spend their time, and what organisms are in those places for them to eat: manta rays swim in the top of the water column, and stingrays hang out on the bottom.
Manta rays do not hunt for their food, they filter feed. This means that they filter plankton out of the water as they swim. They use the two fins on either side of their head to help guide the zooplankton into their mouths. Zooplankton, or planktonic animals, consist of a mixture of crab larvae, fish eggs, mollusk larvae, tiny shrimp, and other tiny creatures. Manta rays may be the biggest of the rays, but they eat tiny creatures to survive.
Eagle rays use their snouts to dig in the sand and unearth all kinds of small animals to eat. They eat things like crabs, clam, oysters, shrimp, sea snails, even octopus and small fish! They can break through those tough shells using their teeth – two grooved plates made especially for crunching shells.
Stingrays hunt for their food and will eat clams, small fish, sea worms, shrimp, and oysters. They move along the bottom and can skim the ocean floor for food. When they do find something to eat, they suck it into their mouths like a vacuum and then chew it quickly.
Lifespan of Rays
The lifespan of rays is dependent on what species it is. Some species of stingray only live for 6-8 years, while eagle rays are hypothesized to live up to 25 years. Not much is known about the growth and development of ocean-crossing manta rays, but some have been reported to live for 40 years.
Are Rays Dangerous?
In short, no. Like many creatures in the sea, rays are only dangerous if they are intentionally provoked. They’re generally shy around humans, and you can consider yourself lucky if you see one in the wild!
Fatal stingray attacks are famous because of Steve Irwin, “the Crocodile Hunter”, but they are extremely rare. Most stingray “attacks” are an accident – if a human steps on a stingray buried under sand, and the stingray panics. Most of these stings have been described as similar to a jellyfish sting – a pain that dissipates in a few hours with professional medical care.
How to Identify Which Ray?
In the water, how do you tell the difference between these kinds of rays? The easiest method is location.
A stingray will often be found on the seafloor, resting under sand or swimming along the bottom to find a good spot to feed. Manta rays and eagle rays will be in the water column, closer to the surface.
If you’re scuba diving, you’ll often have to look up to see these majestic creatures. Remember that manta rays have horn-like cephalic fins on either side of their mouth for guiding plankton in and are much bigger than eagle rays.
In science, sometimes we use dichotomous keys to identify creatures in the wild based on observable traits. These questionnaires guide you to your species with some easy yes/no questions. Here’s an example of one to try out with your fabulous ray pictures:
- What was your ray doing?
- Swimming in the water column – go to Question 3
- Resting on the seafloor – go to Question 2
- Is this ray diamond shaped with very triangular fins?
- Yes – Go to Question 4
- No, it has a very rounded diamond shape – Congratulations, you saw a stingray!
- Does this ray have cephalic fins?
- Yes – Congratulations, you saw a manta ray!
- No – Go to Question 2
- Is the ray bigger than 3 m (9 ft)?
- Yes – Congratulations, you saw a manta ray!
- No – Congratulations, you saw an eagle ray!
Threats to Manta Rays, Eagle Rays and Stingrays
If you have the joy of seeing a stingray, an eagle ray, or a manta ray, that experience is extra special because 1) those encounters are rare, and 2) because the future of these creatures is uncertain. While some species are doing well, species of stingrays, eagle rays, and manta rays all over the world have populations that are decreasing. Rays are fished for human consumption, accidentally caught in fishing vessels targeting other species, or hunted for their gill rakers. Loss of their habitat and climate change also affect stingrays.
However, in 2015 a group of experts created a 10-year strategy to protect sharks and rays on a global scale. This plan involved several international organizations and hopes to continue to expand conservation efforts while also creating stronger management of fisheries to prevent overfishing. More information can be found here: Shark Advocates International.
One of the best ways to share the importance and beauty of these animals is to use our access to the underwater world – scuba diving, snorkeling, swimming – to take photos and share our experiences with those who aren’t able to see rays in real life. Best of all, you can share your new knowledge about what kind of rays you’re seeing, and what makes these related and majestic animals different.