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“Always read something that will make you look good if you die in the middle of it.” P.J. O’Rourke

May 20, 2011 by Leave a Comment

Today Ira Flatow discussed summer science reads on Science Friday, my favorite radio program. So, I got to thinking about two very special books that I always wander back to when I want to reconnect with the ocean. Henry Beston’s, The Outermost House, and Jennifer Ackerman’s, Notes from the Shore, are two books written in the spirit and tradition of Thoreau’s, Walden. Beston and Ackerman are alone with their thoughts in a remote marine environment (Beston is on Cape Cod while Ackerman is on Delaware’s Cape Henelope) for an extended period of time. They both contemplate how the ocean can be a metaphor for our existence.

After his return from World War I, Beston built a writer’s cabin on Cape Cod. He called the home Fo’castle and there he wrote The Outermost House published in 1928. This book was an inspiration to Rachel Carson as she wrote The Sea Around Us. Fo’castle was unfortunately destroyed by high tides in 1978.

Here is an excerpt from The Outermost House that I come back to often (especially when I am coveting the latest smartphone): “Touch the earth, love the earth, her plains, her valleys, her hills, and her seas; rest your spirit in her solitary places. For the gifts of life are the earth’s and they are given to all, and they are the songs of birds at daybreak, Orion and the Bear, and the dawn seen over the ocean from the beach. ”

Let’s face it. Beston is not for everyone. Jennifer Ackerman is a bit most contemporary in her text and prose. After all, Notes from the Shore was published in 1995. Her outlook on man altering nature is spot-on, “It’s in our nature to see order and when we don’t see it, to try to impose it. We have to put things through our minds to make sense of them, and our minds crave pattern and order. So maybe what we glimpse is only what we desire.” A statement that reminds me sometimes we should just allow nature to take its course and see what happens.

Another reason I gravitate to Notes from the Shore is that she spends a considerable amount of time writing about my favorite animal, Limulus polyphemus. She even reviews her experience counting horseshoe crabs during the late nights in May and June, an activity this Beach Chair Scientist did quite often during undergraduate internships. With that I will leave off with Ackerman’s description on the incredible nature of the horseshoe crab‘s ability to remain so steadfast and unchanged, “These creatures so durable that they antedate most other life-forms, so adaptable that their survival as a species may, for all we know, approach eternity.”

Image (c) goodreads.com

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Filed Under: Atlantic Horseshoe Crab, Beach, Fish, Ocean, Random Fun! Tagged With: , , , ,

It’s as easy as A, B, Sea: X for Xiphosura

February 27, 2011 by Leave a Comment

Xiphosura is the order of the Atlantic horseshoe crab and its three closest living related species.

Filed Under: Atlantic Horseshoe Crab

It’s as easy as A, B, Sea: H for Horseshoe Crab

February 8, 2011 by 1 Comment

 

Horseshoe crabs are an arthropod more closely related to spiders and scorpions than crabs and lobsters. They have a three part body: prosoma (head), opisthosoma (heavy shell with legs under it) and the telson (tail). This amazing body structure has been unchanged for over 200 million years. Interestingly enough, this is this Beach Chair Scientist’s favorite animal and there have been numerous posts about Limulus polyphemus. Read more here.

 

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Where have all the horseshoe crabs gone?

August 31, 2010 by 1 Comment

If you’ve kept on eye on the sandy shores of the Atlantic Ocean or eastern Gulf of Mexico over the past twenty years you’ve noticed a significant decline in the number of horseshoe crabs, Limulus polyphemus, covering the beach. As a marine educator and naturalist in my past life, I always said the decline was due to over harvesting for bait and pharmaceutical needs. This is only half the reason. Recently scientists also noted that climate change, with the sea level rise and temperature fluctuation, may be a cause of the decline.

Tim King, a scientist with the United States Geological  Survey, thinks that what happened during the Ice Age could happen again. With climate change comes a loss of habitat and a loss of diversity. These issues could have severe implications, not only for horseshoe crabs, but also for species that rely on them for sustenance. For instance, along the Delaware Bay the red knot eats the horseshoe crabs eggs at the midpoint of their migration. In the Chesapeake Bay, loggerhead sea turtles are struggling to find one of their favorite food sources, horseshoe crabs, and are retreating elsewhere to find food. Now that the link of a decline in the horseshoe crab population and climate change has been made fisheries managers can take this into consideration.

Images (c) Greg Breese, US Fish and Wildlife Service

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A Few Lines from Rehoboth Beach by Fleda Brown

August 4, 2010 by Leave a Comment

Dear friend, you were right: the smell of fish and foam
and algae makes one green smell together. It clears
my head. It empties me enough to fit down in my own

skin for a while, singleminded as a surfer. The first
day here, there was nobody, from one distance
to the other. Rain rose from the waves like steam,

dark lifted off the dark. All I could think of
were hymns, all I knew the words to: the oldest
motions tuning up in me. There was a horseshoe crab

shell, a translucent egg sack, a log of a tired jetty,
and another, and another. I walked miles, holding
my suffering deeply and courteously, as if I were holding

a package for somebody else who would come back
like sunlight. In the morning, the boardwalk opened
wide and white with sun, gulls on one leg in the slicks.

Cold waves, cold air, and people out in heavy coats,
arm in arm along the sheen of waves. A single boy
in shorts rode his skimboard out thigh-high, making

intricate moves across the March ice-water. I thought
he must be painfully cold, but, I hear you say, he had
all the world emptied, to practice his smooth stand.

Read more about this author here.

Filed Under: Algae (Seaweeds), Atlantic Horseshoe Crab, Beach, Egg Cases, Ocean, Random Fun! Tagged With: , , , ,

Just Flip ‘Em

June 25, 2010 by Leave a Comment

If you do not already know, the Atlantic horseshoe crab is my favorite animal. It just breaks my heart when I am home and see a few crabs stranded along the wrackline. One thing that can be done for the animals that are still alive is to ‘Just Flip ‘Em’ (JFE).

JFE is a program from the Ecological Research & Development Group, Inc. that promotes to the public the importance of flipping the gentle crustacean over so they can get back into the sea. A lot of folks are hesitant but the horseshoe crab cannot sting or bite you. The most important piece or information to remember is to flip them from the sides of their shells. This simple act can save thousands of crabs.

Image (c) horseshoecrab.org

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Why are horseshoe crabs essential to biotechnology?

April 28, 2009 by Leave a Comment

First of all, let’s chat biotechnology, or, ‘biotech’, as those in the industry call it.

The concept of biotech has been around for ages, just, not given the fancy term. For instance, planting seeds to produce food, fermenting juice for wine and churning milk into cheese (that are tested with the help of mycotoxin testing kits for the quality) are all processes that use some derivative of a plant or animal to benefit mankind. In the biotechnology and pharmaceutical fields of today, the Atlantic horseshoe crab (Limulus polyphemus) blood is a very important component in the process for testing drugs that can benefits humans that can be produced using nonhuman primate CRO method.

Their blood is used for the  Limulus Amebocyte Lysate (LAL) test is used to test for gram negative bacteria contamination in certain products before being released to the public. Horseshoe crab blood cells (amoebocytes) attach to harmful toxins produced by some types of gram negative bacterias. What is unique with the LAL, is that LAL does not distinguish between living or dead gram negative bacteria and detects either.

You do not want anything with a gram negative bacteria contamination. Gram negative contamination include: Escherichia coli, Salmonella, Neisseria meningitidis, Hemophilus influenzae, Klebsiella pneumonia.

The blood of the horseshoe crab has this unbelievable property where it will congeal in the presence of either living or dead gram negative bacteria (both are undesirable). This adaptation has never been able to be duplicated and consequently horseshoe crabs are often captured to have their blood drained and then released, all in the name of science.

Do you have another great question? Check out www.beachchairscientist.com and let us know what you always ponder while digging your toes in the sand!

Filed Under: Atlantic Horseshoe Crab

Are horseshoe crabs dangerous?

April 23, 2009 by Leave a Comment

No. I mentioned in the very first BCS blog entry that the horseshoe crab is a “sweetheart of an animal” and I will continue to defend that statement. Some people may think that the tail spine, or telson, is poisonous. What the telson is simply used for is to flip the animal over when a wave turns it onto its carapace. The tip of the telson is jabbed into the sand and the horseshoe crab rights itself over, somewhat like the act of throwing a javelin.

Do you have another great question? Check out www.beachchairscientist.com and let us know what you always ponder while digging your toes in the sand!

Filed Under: Atlantic Horseshoe Crab

Why do I always see so many dead crabs along the shoreline?

February 19, 2009 by Leave a Comment

Rest assure those crab skeletons are not all dead crabs. They are the molts from the animals. Crabs, lobsters, horseshoe crabs, and many other crustaceans go through a molting phase and the old shell is basically washed up in the wrack line.

The wrack line is the deposits from the ocean after the tide has gone back out to sea. It’s often defined by seaweed that entangles lots of fun ocean treasures such as sea beans, old leathery sea turtle eggs, and sometimes marine debris. It’s my favorite spot to explore!

Do you have another great question? Email info@beachchairscientist.com and let me know what you always ponder while digging your toes in the sand!

Filed Under: Algae (Seaweeds), Atlantic Horseshoe Crab, Beach Tagged With: , , ,

More reasons why I love the Atlantic Horseshoe Crab…

September 11, 2008 by 3 Comments

As I mentioned before, the horseshoe crab is a rather frightening looking creature, however quite the opposite is true, they are the steadfast, strong member of the ocean community. This animal, not only is a vital part of the Atlantic coast food chain, but has remained rather unchanged since before the time of the dinosaurs!

An animal that has been in existence since before the dinosaurs is quite impressive and the main reason I have gotten my 4 year old nephew to learn and love saying the scientific name for the Atlantic Horseshoe Crab, Limulus polyphemus. The “polly-femus” part always cracks him up.

But, seriously, they have remained relatively unchanged and evolved little in 260 million years!

How have they managed this impressive feat?

First of all, it is very difficult for predators to get overturn their tough curved shell and get into the crux of their underbelly!

Secondly, they can go a year without food!

Lastly, they are adaptable and can endure the harshest conditions (temperature and ocean salt levels)!

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

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