Operculum is the hard scalelike cover of the gills of bony fishes. Cartilaginous fishes (such as sharks, skates and rays) all lack a gill cover.
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- September 14, 2026
Marine & Freshwater Environmental Education
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Quick deep sea coral tutorials
Did you know that corals are living in the deep sea? That’s right, they’re aren’t only a part of the vibrant sunny reef ecosystems we’ve grown to know and love while watching movies like Finding Dory or Chasing Coral. Some species of coral live in complete darkness and withstand incredibly cold temperatures. They are just […]
Jellywatch
It is gearing up for summertime so if you see a jellyfish on the beach, report it here. They actually want to hear about all your fun and exciting ocean finds. And best of all there is no registration – so get to it!
LISTEN UP: Over a dozen #PlasticSucks radio stories
Huge news yesterday! The UK may ban plastic straws, stirrers, and cotton swabs (by Laurel Wamsley). To me, this indicates that there is an understanding that it’s not just because our planet looks disgusting with all of the plastic littered about, but that governments are getting the full picture that plastics are also deteriorating our […]
Test your knowledge: Sea stars
1. True or False: Sea stars are fish. 2. True or False: Sea stars are closely related to sea cucumbers, sea urchins and brittle stars. 3. True or False: Sea stars have a flexible skeleton. 4. True or False: Sea stars breathe through gills. 5. True or False: Sea stars can regenerate most body parts. […]
Why does a sea urchin attach seashells to itself?
You may not notice it, but sea urchins have very thin tube-like suction cup feet, just like their close relative the sea stars. These feet are useful to grasp onto pieces of seashells, pebbles, or seaweed to disguise the sea urchin from other nearby predators. Click on this post to see what eats a sea […]
Christmas critter countdown: Red drum
Red drum have an ability to produce a drumming sound on their air bladders which is how they got commons name. Learn who what other fish share this characteristic with them here. Pa-rum-pa-pa-pum …
Top 5 beachcomber questions answered
Take a look at this quarter’s top 5 reasons folks end up on our site. (Due to the amazing power of WordPress I can see what you’re typing into a search that would lead you here!) 1. How do fish give birth? 2. How do flamingos get their color? 3. What is the biggest fish […]
What makes the swirly tracks at the ocean edge?
What I think you are referring to is the trail of a moon snail, or sometimes called a sand snail. This univalve animal has a cinnamon bun swirled shell. The shell is extremely thick to protect itself from the ocean and other animals that may try to eat it. If you try to pick it […]
Don’t hide your head in the sand
A few weeks ago I had the pleasure meet up with Jen Miller, a freelance reporter, to discuss some of the little known and finer attributes that the often pesky ‘sand’ brings to our beaches. For instance, did you know that all beach sand contains quartz? The odd thing is that the land surrounding some […]
Why is the blood of horseshoe crabs blue?
Horseshoe crabs use hemocyanin to distribute oxygen throughout their bodies. Hemocyanin is copper-based and gives the animal its distinctive blue blood. We use an iron-based hemoglobin to move oxygen around. The blood of this living fossil has the ability to clot in an instance when it detects unfamiliar germs, therefore building up protective barriers to […]
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- Hurricane vs. Cyclone vs. Typhoon
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- Beyond the bag: Other plastics being banned
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