Tag Archives: Rays

Rays vs. Skates

Snorkeling above the sandy bottoms of CIMI’s shores, you might spot a cute little ray shuffling along… or is it a skate? No wait, it is a ray! But it might be a skate. Maybe. These closely related cartilaginous fish can certainly be difficult to tell apart, but each has certain qualities that make it unique and distinguishable.

rays vs skates

Though both rays and skates have flattened bodies with which they can hide on the ocean floor, skates typically have fleshier tails with enlarged, thorny scales running along their backs for protection. Meanwhile, most rays have thinner tails barbed with one or two stinging spines that ward off potential predators. If you happen to see these guys moving about, you might observe that they swim differently too. Skates move by undulating their tails left and right, whereas rays flutter and flap their pectoral fins to get where they need to go.

Beyond the differences that you might notice at a glance, rays and skates have unique life cycles with disparate modes of reproduction. Skates are oviparous, which means that they reproduce by laying eggs. These eggs (or “mermaid purses” as they’re often called) are dark and flat with small projections that keep them anchored to marine substrate. Each egg is equipped with nutrients to keep the developing skates healthy for up to 12 weeks, at which point the pup will hatch and take on the big bad ocean. Rays, on the other hand, are viviparous, meaning that they give live birth to their pups. The gestational period (a.k.a. pregnancy) of some ray species can last over a year and once born, the juvenile rays usually separate from their mothers.

Ever Wonder What These Things Are?

The next time you find yourself face to face (or fin to fin) with a flat cartilaginous fish, remember these differences so that you can distinguish the tail-stinging, fin-flapping, birth-giving rays from those back-spiking, tail-swinging, egg-laying skates.




Musical Fish

Did you catch those incredible songs performed by our very own musically inclined friend, CIMI Shark?? Yep, we created that music to your ears to help you guys remember some of our favorite sea creatures that we sometimes see out on our snorkels!


We call these musical cartilage fish Chondricthyes, or cartilage fish. First, there’s the old DUH NUH NUH NUH NUH NUH NUH NUH NUH BATRAAAAY!!!! That’s the jive for our dear friend the bat ray, and you should sing it at the top of your lungs into your snorkel if ever you happen across one of these flapping beauties out in the water. We’ve got more songs where that came from, but of course we love most to hear the ones you come up with!


So what do our musical fish have in common? Sharks, Skates, and Rays are all cartilaginous fish, meaning they don’t have any bones! Instead, they get their structure from hard cartilage that mimics the same boney structures that we have in our bodies. Personally, I’d prefer a solid boney backbone, but these cartilage fish have something called a notochord, which helps provide structure as well as an ability to move with agility through the water. These cartilage fish also lack a ribcage, so if some of the bigger guys were to be taken out of the water, their own body weight would crush their internal organs! Ouch, let’s steer away from picking up a large shark anytime soon…

These musical cartilage fish are super neat because some of them, specifically sharks and rays, have things called dermal denticles. These dermal denticles, or skin teeth, are tiny sharp structures that overlap and provide protection as well as hydrodynamics, or an ability to swim fast in the water. If you’ve ever felt sandpaper, than you’re already familiar with what a shark’s skin feels like. Or if you’ve been to CIMI, than you certainly already know!

So what do all our musical fish have in common? Sharks, Skates, and Rays are made out of cartilage, meaning they have NO BONES!! We will leave you with a word of the wise: Don’t go challenging any of these cartilage Chondricthyes to any limbo contests, because they’d surely win!




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