The Size of Manta Rays: How Big Can they Grow?

Apr 14, 2025 | About Manta Rays

Picture yourself snorkeling in the ocean when suddenly, a massive shadow glides beneath you. Don’t worry – it’s just a manta ray! One of the most common questions we hear from guests is “How big can manta rays be?”

Manta rays are some of the largest fish you’ll ever meet, and while they all seem giant (compared to humans), not every manta is officially called a “giant” manta ray.

The Species of Manta Rays

Scientists recognize two (possibly three) distinct species of manta rays, each with its own characteristic size range:

Giant Oceanic Manta Ray (Mobula birostris)

The giant oceanic manta ray truly lives up to its name: These majestic creatures can reach a wingspan (known as disc width) of up to 29 feet (8.8 meters) – wider than a small private airplane!

While this represents the maximum recorded size, most adult oceanic mantas typically measure between 15 and 23 feet (4.5 to 7 meters) across. Their substantial size makes them the largest ray species in the world and one of the biggest fish species overall.

Reef Manta Ray (Mobula alfredi)

While slightly smaller than its oceanic cousin, the reef manta ray is still an impressively large animal. Adult female reef mantas generally reach a wingspan of 10 to 15 feet (3 to 4.5 meters).

Despite being the smaller species, encountering a reef manta ray remains an awe-inspiring experience – imagine swimming alongside a creature with a wingspan wider than your car!

When you encounter “giant” manta rays in the ocean, these will likely be reef mantas, as they stay closer to the coast while their bigger cousins like to roam deeper in the ocean.

The Caribbean Manta Ray (Mobula cf. birostris)

The Caribbean manta ray (or Atlantic manta) is found in the Caribbean and Gulf of Mexico and may have evolved from oceanic mantas that adapted to the area’s shallow reefs… the jury’s still out, as scientists have only just begun to explore the possibility of this being a third species.

The Caribbean manta is smaller than the oceanic manta ray, and similar in size to the reef manta ray, with an average wingspan of 10–13 feet (3–4 meters) and a maximum disc width of 16.5 feet ( 5 meters).

Size Development and Growth

Manta rays begin life much smaller than their adult size. A newborn reef manta typically measures about 2 to 3 feet (60 to 90 centimeters) across, while an oceanic manta pup starts at approximately 6.6 feet (2 meters) in width.

They grow steadily throughout their lives, though growth rates slow significantly after reaching maturity.

Several factors influence a manta ray’s ultimate size:

  • Gender: females typically grow larger than males
  • Geographic location and available food resources
  • Overall health and environmental conditions
  • Age: the older, the bigger, but once a manta reaches maturity, it will stop growing

Manta Ray Size Comparison

To truly appreciate the scale of these magnificent creatures, consider these comparisons:

  • An adult reef manta ray’s wingspan is about twice the height of a tall human
  • A large oceanic manta ray could span the width of a school bus
  • Even a “small” adult manta ray typically has a wingspan wider than a king-size bed

Despite their impressive dimensions, manta rays remain incredibly graceful swimmers. Their size, gentle nature, and fluid movements create an almost hypnotic effect as they glide through the water.

Graphic showing the difference in wingspan of giant manta ray and reef manta ray

Why Size Matters

The substantial size of manta rays plays a crucial role in their survival and behavior:

  • Larger bodies can store more energy, allowing mantas to travel long distances
  • Their size helps maintain body temperature in varying ocean conditions
  • A larger wingspan enables more efficient filter feeding
  • Their adult size offers protection from most potential predators

While their size might seem intimidating at first sight, manta rays are entirely harmless to humans. They are filter feeders with no stinging barb, preferring to feast on microscopic plankton. They cannot digest any larger prey.

Whether you’re fortunate enough to encounter a reef manta ray during our nighttime snorkel adventures or simply learning about these incredible animals, their impressive size is just one aspect of what makes them fascinating creatures worthy of our admiration and protection.

Want to learn more fascinating facts about mantas?

Download our Manta Ray Facts & Figures eBook and learn what makes these gentle giants some of the most incredible ocean creatures.

Comments

0 Comments

Submit a Comment

Your email address will not be published. Required fields are marked *

More things you’ll love!

Manta Rays Myths and Legends Around the World

Manta Rays Myths and Legends Around the World

Behind the Scenes: How Georgia Aquarium Gives Manta Rays an Annual Check-up

Behind the Scenes: How Georgia Aquarium Gives Manta Rays an Annual Check-up

How Fast Can Manta Rays Swim?

How Fast Can Manta Rays Swim?

Why Manta Rays are the Gentle Giants of the Ocean

Why Manta Rays are the Gentle Giants of the Ocean

Tracking the Movement Patterns of Reef Manta Rays in Hawaii

Tracking the Movement Patterns of Reef Manta Rays in Hawaii

Cutting Corners: Tourist Boat Practices that Harm Humans and Mantas

Cutting Corners: Tourist Boat Practices that Harm Humans and Mantas

No results found.

We participate in referral programs, and this website contains affiliate links. If you buy something after clicking a link on this website, we may get a commission – at no extra cost for you.

We only include products we love and wholeheartedly recommend. Read more here.

Free Downloads

Manta Ray Facts & Figures Ebook

Amaze your friends and family members with your knowledge of the gentle giants.

→ GRAB YOUR COPY

Guide to Swimming with Manta Rays

All the things you need to know before you embark on this adventure of a lifetime.

→ GET IT NOW

10 Tips for Marine Photography

Learn to capture life-changing moments underwater.

→ I NEED THIS

Pin It on Pinterest

Share This

Share this post with your friends!