April 3, 2011

Sand Dollars Along Anna Maria Island Coast


One of my favorite things to do in the morning is to walk along the beautiful stretches of beach on Anna Maria Island.  I look for sand dollars washing up in the surf. Almost everyday I find one or two whole sand dollars and consider it my lucky day!


 They range in size from an average three inches in diameter to tiny baby sand dollars.  Sometimes I'll find parts of very large ones with diameters of five to six inches.  



 Sand dollars are found in sandy, shallow water, although some are found in deep ocean floors throughout all the world's oceans. Mostly, they live in groups near land.

 You might have heard that picking up a sand dollar and keeping it is wrong because it is a "live" animal.  Most beaches and state parks have strict rules against taking any live sea life from their home, so please honor those laws.

                                         photo:theradula.com

Sand dollars are marine animals so please be sure not to disturb live ones.  A live sand dollar is brown, dark tan or even a purple with many tiny moving brown spines covering its surface.  These little "arms" enable the sand dollar to move along the ocean floor as well as obtain food and push it into its mouth.  It has a "velvety" feel.  

Most sand dollars have five sets of pores on the surface, which is used to move seawater into the body where it is pumped to aid in movement and internal functions. 
                                                  photo:questconnect.com

Pick up only the white ones, and you'll be fine.  The sand dollar skeletal shell is smooth, hard and white, so by the time it washes up on the beach, its probably no longer living.  Just the shell remains, so it’s fine to collect these.  If you come across a brown one with moving fuzzy spines, just toss it back to the sea. 
 Curious about how these little creatures reproduce?  The female discharges already ripe eggs and the male then fertilizes them externally.  Females can produce over 350,000 eggs per year.  The baby sand dollars develop into several stages until the hard skeleton starts to form, then they drop to the bottom and live in groups for the rest of their lives.
photo:flickr
Not many sea creatures bother the sand dollar since they don't have much in the way of edible parts and the skeleton is pretty hard. If the water is fairly calm, you might be able to see a sand dollar stand on its edge wedging itself in the mud.  In areas of strong currents and tides, sand dollars burrow into the soft sandy bottom. Sometimes they actually swallow sand grains to add weight so they're not washed away!

photo:scuba-explorers.com

If you find sand dollars along the beach (low tide after a storm is the best time), then you might want to preserve them, since they are brittle.

Try these simple steps:
-soak it in fresh water
- rinse, then soak in 2/3 fresh water and 1/3 bleach for 15 minutes.
-rinse and let dry
-mix water and white glue in equal portions
-brush on and let dry.
Now, you're ready to display your find!
photo:coastalcottages
If your sand dollar breaks, no worries.  Use this as an opportunity to check out the anatomy of this unique sea creature.  You might hear something rattling inside.  Shake it out into your palm and, as legend tells it, there will be five little "doves" waiting to spread good will and peace. 
photo:mitchelpublications.com

To see live sand dollars in action, check out the videos below: 
photos:flickr
videos: Youtube

Just one more bit of info.  
There are several different types of sand dollars:
Arrowhead:
    
Flat Round:



Sea Biscuits:
Pancake:
 Sea Gopher:
photos courtesy seashells.org
I usually find the flat rounds, but have found arrowheads, too.
Let me know what you find!

5 comments:

  1. Love these videos. Found a lot of broken sand dollars this morning along the Gulf side beach near Palm St. I guess they are very delicate. But, since they're showing up in the surf, there must be
    groups of them nearby. Will keep looking tomorrow

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  2. My son, Jason, found two small sand dollars near Bean Point earlier today. We are planning to preserve them with your white glue method so we can bring them home without damaging them.

    Thanks for the info!

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  3. Very interesting videos about live sand dollars. It looks like they inspired the invention of swimming pool vacuums with the circular motion. I think there's a home vacuum that rotates, too.
    Nature is incredible.

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  4. Love the blog on sand dollars! And beach furniture! Will try the white glue on a few sand dollars Randy found .... plus we have a new eye on wood dressers to whiten them up!

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  5. I went to San Diego a few moths ago and found almost a dozen white sand dollars! These videos are so cool because I have never seen a live one! Great blog!

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