The Master Regulators: The Purple Sea Urchins

Katelyn Vickery and Maria Fam
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Purple Sea Urchins are beautiful creatures and are known for their numerous spikes which aid with locomotion as well as protection. Strongylocentrotus purpuratus. © David Monniaux

When two years of age

January, February, March each year,

They breed by releasing gametes into the ocean,

It all depends on the surf, it appears,

If it's violent, the gametes cannot survive because it’s all in the motion.

But, if they survive, they can start their life, a new page.


Algae is their food,

“Grazers of the marine algae”: they have been named,

Their duty is to maintain the amount of algae when in the mood,

They have a role as an herbivore, as proclaimed

And they enjoy eating kelp

During tidal waves, the kelp are washed away,

The purple sea urchins eat the young kelp who cry for help.

When there are none left, the urchins must pay.


These species is common, in the present,

But, in the future, they might be in danger,

In Japan, people find sea urchin sushi quite pleasant

The Department of Fish and Game are trying to help these strangers

These creatures are harvested at fisheries in a beat,

Other species enjoy eating their food: us

We are taking all we can plus…

We are leaving them with nothing to eat


Purple sea urchins are found in shallow parts

Specifically on a coast with strong waves,

They are unlikely to be apart

One can find them on the east coast of America

As well as on the Pacific coast, according to the editors

Sheep-head fish, spiny lobster, otters are their predators

However, they are brave

They use their spikes

And they continuously put up a fight

These spikes are also used for mobilization

What an idea, a sensation.

About This Page

Author: Katelyn Vickery and Maria Fam
Classroom Project: Organism Research and Creative Story Telling
Ashbury College School
Ottawa, Ontario K1M 0T3 Canada

License: Creative Commons Attribution-NonCommercial License - Version 3.0

Correspondence regarding this page should be directed to , Ashbury College School

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