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Can we eat sea cucumbers?

June 8, 2010 by 4 Comments

There’s a funny animal that lives on the floor of the ocean and likes to eat what most of us would only wipe off the bottom of our shoes. It’s name is the sea cucumber. The sea cucumber is an echinoderm and is closely related to sea stars, sea urchins, and sand dollars.To protect itself the sea cucumber will expel its intestines outside of its body to distract predators. The sea cucumber is a prized Japanese culinary tradition used often in soups and stews. Fisheries along the Atlantic coast have been popping up in the past twenty years to sell sea cucumbers.

Check out this video from National Geographic on how they (literally) fight with guts for glory:

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Can a sea star see?

May 6, 2010 by Leave a Comment

Not in the traditional sense that you and eye see, I mean, you and I see.

Sea stars (Sidenote: since they are not ‘fish’ sea stars, as opposed to starfish, is more appropriate) have an eyespot at the tip of each “leg”. These eyespots can distinguish between light and dark and other stimuli and the sea star is able to react to what they sense.

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Filed Under: Echinoderms

Answers to “Test your knowledge of sea stars”

January 3, 2010 by Leave a Comment

Answers to “Test your knowledge of sea stars” from December 31, 2009.

True or False: Sea stars are fish. They are echinoderms, a group of invertebrates. Invertebrates have no backbones. All fish have backbones.
True or False: Sea stars are closely related to sea cucumbers, sea urchins and brittle stars.
True or False: Sea stars have a flexible skeleton.
True or False: Sea stars breathe through gills. They breathe through a water vascular system. You can see the tube feet (a main component of the water vascular system) on the underside of the sea stars.
True or False: Sea stars can regenerate most body parts.

Congrats to all those that got them correct!

Filed Under: Echinoderms, Ocean, Random Fun!, Test Your Knowledge

Test your knowledge: Sea stars

December 31, 2009 by 2 Comments
Sea star and sea urchin

Image by B.K. Dewey via Flickr

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.

(Answers can be found here.)

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Why does a sea urchin attach seashells to itself?

April 23, 2009 by Leave a Comment

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 urchin.

But we’ve only scratched the surface here. Check back often at http://www.beachchairscientist.com for more insight about your favorite beach discoveries.

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How long do seastars live?

March 6, 2009 by 4 Comments

Seastars can live up to 35 years in the wild! It really depends on the species. Their wild habitat includes coral reefs, rocky coasts, sandy bottom, or even the deep sea of all the world’s oceans. There are approximately 1,800 different types of sea stars.

They have been known to live up to 10 years in aquariums.

More links on seastars:

http://animals.nationalgeographic.com/animals/invertebrates/starfish.html

http://users.bigpond.net.au/je.st/starfish/index.html

But we’ve only scratched the surface here. Check back often at http://www.beachchairscientist.com for more insight about your favorite beach discoveries.

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Is a starfish really a fish?

February 20, 2009 by 1 Comment

No. The classic common name is very misleading. Scientists and environmental educators are transitioning their language to seastar when referring to this animal because, well, it is not a fish.

The seastar is in the same family as the sea urchin, sea cucumber, sand image_sci_animal021dollar and a few others that all have these things in common: fivefold radial symmetry, spiny skin and a water based vascular system.

The family is called the “echinoderms” which means spiny skinned.

Image (c) dk clipart.

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Filed Under: Echinoderms

How do sea stars eat?

November 18, 2008 by 4 Comments

StarfishFirst, sea stars grip their prey (e.g., bivalves, such as clams and oysters) with their suction feet and pry them apart to eat the muscle inside the shells. Then, once the bivalve’s shell is open, the stomach of the sea star emerges from the middle of the underside of its star-shaped body to absorb the delicious entrée inside itself. After this happens, the animal is full and not going anywhere soon (e.g., me after Thanksgiving dinner).

A sea star is another common name for starfish. Scientists, and the likes of me, are on a campaign to get people to refer to this echinoderm as the ‘sea star’ instead of a starfish. Since, well, they simply are not fish. Similarly, jellies are not called jellyfish anymore.

Check out this video from the Monterey Bay Aquarium of a sea star chowing down!

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What eats sea urchins?

September 10, 2008 by 7 Comments
Sea Urchin (Diadematidae) (20 cm)

Image by CybersamX via Flickr

The spines of the sea urchins are there for protection but that doesn’t stop the sea urchin from having enemies. 

For instance, sea gulls love to grab them at low tide at pick away at them high upon the rocks. Crabs have a feast with the urchins by picking away at their spine to get to the inside flesh. Also, urchins that are found along the ocean floor are preyed upon by rays, sharks, seals, and even otters.

But we’ve only scratched the surface here. Check back often at www.beachchairscientist.com for more insight about your favorite beach discoveries.

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