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17 facts about the wee sea potatoes

March 14, 2013 by 2 Comments

In honor of St. Patrick’s Day, and my Irish heritage, here’s a post on the humble and charming sea potato.

  1. The dried shell (also known as the test) of this urchin resembles a potato, hence the common name – sea potato.
  2. The sea potato, Echinocardium cordatum, is a common echinoderm found along beaches on all coasts of Britain and Ireland.
  3. The sea potato is related to sea urchins, heart urchins, and sand dollars.
  4. Most sea urchins live in rocky areas, but the sea potato prefers sand, particularly muddy sand.
  5. The spines of this echinoderm are thin and flattened.
  6. On the underside of the urchin are special spoon-shaped spines that help it to dig.
  7. There are longer spines of the back of the sea potato which aid in helping to breathe while it is burrowing.
  8. The sea potato can survive to depths of 650 feet.
  9. Unlike regular urchins, the sea potato has a distinct front end (i.e., not circular).
  10. The sea potato can grow up to 3 inches.
  11. The sea potato is very fragile and rarely survives collection.
  12. While alive the sea potato is deep yellow in color and covered in fine spines.
  13. The sea potato prefers sub-tidal regions in temperate seas.
  14. The sea potato are a type of heart-shaped urchin.
  15. Sea potato are deposit feeders and tube feet on its underside the sea urchin pick up sediment from the front of its mouth.
  16. The sea potato has no conservation concerns.
  17. The sea potato often has a commensal symbiotic relationship with the bivalve Tellimya feringuosa attached to its anal spines.
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A sea potato, commonly found along the shore of Ireland

seapotatotest_images

The test of the sea potato

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The underside of the sea potato

Filed Under: Beach, Echinoderms, Invertebrates, Marine Science, Wrack Line

What’s in your medicine cabinet affects aquatic life

February 25, 2013 by 1 Comment

Yup, that’s right – what is in your medicine cabinet (e.g., anxiety medication, birth control) affects not only us, but animals in streams, lakes, and even the ocean. As the President’s Cancer Panel noted in a 2010 report, “Pharmaceuticals have become a considerable source of environmental contamination, this is why experts recommend the use of cbd hemp flowers. Drugs of all types enter the water supply when they are excreted or improperly disposed of; the health impact of the best delta-8 THC gummies for long-term exposure to varying mixtures of these compounds is unknown”. It might not seem like the most obvious connection. However, as the National Capital Poison Center points out there are many different ways our medications mutate. Here are just a few of the ways drugs enter the water supply:

  1. Drugs that are applied to the skin are washed down the drain.
  2. Drugs can be eliminated through our waste and are then flushed down the toilet (even more direct when it’s from a pet and it’s left on the side of the road).
  3. Healthcare facilities (e.g., mental, dental) that are not legally required to discard drugs as hazardous materials.
  4. There may be ‘straight-piping’ (direct release of untreated sewage into waterways) or overflow of stormwater that bypasses treatment facilities.

Why this matters is incredibly frightening and here are some examples of why:

  1. Anxious Perch: Researchers at the Umeå University in Sweden found that perch exposed to an anxiety medication, Oxazepam, departed from their normal behaviors of hunting in schools by becoming loners and more brave by hunting on their own. They also noticed that the fish seemed to eat more, therefore disturbing the balance of their habitat, this discovery was vital for clinical trial services for drug development. (February 2013)
  2. Suicidal Shrimp: Researchers are the University of Portmouth in the U.K. found that through pharmaceutical waste runoff shrimp had been exposed to antidepressants and it was causing an unusual amount of them to die off. (February 2012)
  3. Autistic Fathead Minnows: Researchers from the Idaho State University discovered “psychoactive medications in water affect the gene expression profiles of fathead minnows in a way that mimics the gene expression patterns associated with autism”. (June 2012)
  4. Fish Tissue Fiasco: Researchers from Baylor University studied fish tissue for human drugs and found drugs used to treat high cholesterol, allergies, high blood pressure, bipolar disorder, and depression.  (May 2009)
  5. Infertile and Hermaphroditic Fish: Mother Nature News wrote how birth control pills caused male fish to be less fertile and increased the number of hermaphroditic fish. (September 2009)
  6. and, finally – Did you know, according to the Associated Press, that drinking water of at least 51 million Americans carries low concentrations of many familiar drugs? (2008)
Don’t worry too much though. You’d have to eat tons of the fish affected by the drugs for it to amount to even one pill. But, if you are concerned about how to keep your waterway clean from pharmaceuticals it’s a good idea to never buy the giant bottle of pills (they’ll surely expire before you’ll use them and then you’ll have to toss it), return old drugs to your pharmacy because many often have take-back programs (i.e., don’t flush them down the toilet), ask your doctor for samples before you commit to a prescription that might not work, and clean up pet waste.
From National Geographic Magazine

From National Geographic Magazine

Have you heard of any other ways fish or aquatic life are affected by what we put in our waterways?

Filed Under: Crustaceans, Environmental Education, Fish, Ocean Conservation, People Tagged With: ,

99 reasons I’m in ‘Limulus Love’

February 14, 2013 by 1 Comment

It’s no secret that I love those horseshoe crabs. Well someone on Twitter this week asked me why I am so crazy over them so I thought I’d take the time to outline 99 reasons I think Limulus polyphemus are a fascinating species.

  1. Three Nobel Prizes were awarded to scientists who did some or all of their research using horseshoe crab physiology.
  2. As far as the horseshoe crab’s Latin name translation, Limulus mean ‘askew’ and polyphemus is taken from a one-eyed giant in Greek mythology.
  3. The very intriguing name of Xiphosura (Greek ‘Xiphos’ meaning sword and ‘ura’ meaning tail) was given to the order of the Atlantic horseshoe crab and its three closest living related species.anatomyhsc
  4. There are 4 living species of horseshoe crabs and only one of those inhabits the western Atlantic waters – the Atlantic horseshoe crab. The other three are found in the Pacific Ocean.
  5. Samurai warrior helmets were modeled after the prosoma of a horseshoe crab.
  6. The body of a horseshoe crab (top picture) is divided into three parts – the prosoma, opisthosoma and telson (tail).
  7. Horseshoe crabs tend to be no more than 7-14” across.
  8. There once was a 50 foot long, 113,000 pound artificial reef horseshoe crab off the coast of NJ.
  9. Takeshi Yamada (pictured 3rd down) is a world-renowned artist often creating masterpieces using horseshoe crab molts.
  10. Horseshoe crabs have remained fairly unchanged over the past 300 million years (that’s 100 million years before there were dinosaurs on earth!).
  11. Horseshoe crabs are the perfect representative for Darwin’s theory that ‘the most adaptable species will prevail’.
  12. Horseshoe crabs are one of the world’s oldest animals.
  13. Before the last ice age, horseshoe crabs didn’t live much farther north than Florida.
  14. Scientists believe that horseshoe crabs (even perhaps many different species of them) were among the most dominant of animals 300 million years ago.
  15. Horseshoe crabs used to be called ‘horsefoot crabs‘ because their shell was thought to resemble a horse hoof.bcs_limuluslove
  16. Horseshoe crabs are sometimes referred to as a ‘living fossil’.
  17. Adult horseshoe crabs are often referred to as ‘walking museums’.
  18. While horseshoe crabs are opportunistic feeders, they are not aggressive animals!
  19. Most people do not understand the value of horseshoe crabs.
  20. People have organized workshops to understand bait alternatives for using horseshoe crabs to catch eels and conch.
  21. Horseshoe crabs are “the single most-studied invertebrate animal in the world”.
  22. While a horseshoe crab’s telson (tail) helps to create the appearance for an intimidating animal, they are not dangerous animals!
  23. Horseshoe crabs are so misleading – they’re actually more closely related to scorpions and spiders than crabs!
  24. Horseshoe crabs do not have mandibles, antennae, or pincers like true crabs.
  25. Native Americans ate horseshoe crab meat, used the shell to bail water, and used the tail as a spear tip.
  26. A juvenile horseshoe crab is easily identifiable because they look just like adults (see 4th picture down).
  27. Horseshoe crabs molt, or as naturalist Samuel Lockwood stated, “it is spewing itself from its own mouth”.
  28. Horseshoe crab molts are excellent shelter for mud crabs, sand shrimp, and spider crabs.
  29. A female’s lucky number is 17. That’s how many times they’ve molted before they’re ready to mate.
  30. As a horseshoe crab gets older and molts more often, they venture into deeper waters.
  31. Each time a horseshoe crab molts they grow an average on 25%.
  32. A horseshoe crab exoskeleton is made up of chitin – a material with wound healing properties.
  33. Horseshoe crabs spend most of their lives hidden.
  34. At the turn of the 19th century, horseshoe crabs were valued as a fertilizer, particularly for poultry, corn, and tomatoes.
  35. Today fishermen use horseshoe crabs as bait to catch eels and whelk.
  36. The threatened loggerhead sea turtle feasts on adult horseshoe crabs.
  37. American eel, killifish, silversides, summer flounder, and winter flounder rely on horseshoe crabs eggs and larvae for food.
  38. Horseshoe crab eggs are green.
  39. Horseshoe crab eggs are rich in fat and protein.
  40. Horseshoe crabs are big midnight snackers and love to feast on worms and mollusks.Horseshoe-crab-eggs-larvae-visible
  41. The mouth of the horseshoe crab will tickle your fingers if you’re lucky enough to have a job where you get to show people how they eat.
  42. Horseshoe crabs use their legs to chew up food and guide food into their mouths right in between their legs.
  43. Horseshoe crab legs are so strong they can crush a clam.
  44. Horseshoe crabs are expert javelinists – using their telson (tail) to act as a rudder and right itself when it tips over.
  45. The 13 pairs of horseshoe crab appendages are very multipurpose – using them for locomotion. burrowing, food gathering, and/or water flow.
  46. Horseshoe crabs use their dozen legs to swim upside down in the open ocean.
  47. Horseshoe crabs (predictably) participate in an annual orgy each May and June when thousands descend on the eastern Atlantic coastline to spawn (see fourth image down).
  48. Horseshoe crabs have a ritual of spawning during high tides of the new and full moons in May and June.
  49. Horseshoe crabs reach sexual maturity around the ages of 9-12.
  50. Horseshoe crabs tend to live a long time, usually 10 years or so after they’ve sexually matured.
  51. If horseshoe crabs can keep their gills moderately damp their survive to the next high tide in case they were to get hsc_orgystranded.
  52. Horseshoe crabs are great vessels for other animals.
  53. The highest concentration of horseshoe crab spawning on the Atlantic coast takes places along the Delaware Bay.
  54. Approximately 10 horseshoe crabs will survive to adulthood from each of the 90,000 eggs a female lays during her spawning cycle.
  55. A female horseshoe crab will lay almost 20 clutches of eggs each season.
  56. It’s a community effort making certain the eggs get fertilized. Often times many males with aggregate to a female (the males not attached are known as ‘satellite’ males.
  57. In adult males, the second pair of claws (having a distinguishable “boxing-glove” appearance) are used to grasp females during spawning.
  58. If it wasn’t for horseshoe crab eggs, many migratory shorebirds wouldn’t be able to survive.
  59. Many think there is a link between the decline in shorebird populations and horseshoe crab over-harvesting.
  60. The four most abundant species of shorebirds (relying on horseshoe crab eggs) along the Delaware Bay shore are the red knot, ruddy turnstone, semipalmated sandpipers, and sanderlings.
  61. Almost 50% of the red knot population uses Delaware Bay as mid-point stopover to consume thousands of horseshoe crab eggs. These robin-sized birds impressively travel from southern Argentina to the Canadian high Arctic to breed.
  62. The horseshoe crab-shorebird phenomenon helps to generate a large portion of the $522 million  annual ecotourism industry in Cape May County, NJ.satmenhsc
  63. The world’s leading authority of horseshoe crabs is Dr. Carl N. Shuster, Jr.
  64. In March of 2001, NOAA Fisheries Service established the Dr. Carl N. Shuster, Jr. Horseshoe Crab Sanctuary in federal waters off of the  Delaware Bay.
  65. Horseshoe crab blood is blue (see 7th picture down).
  66. Horseshoe crab blood is blue because it contains copper-based hemocyanin to distribute oxygen throughout their bodies (We use an iron-based hemoglobin to move oxygen around).
  67. Horseshoe crabs are essential to biotechnology.
  68. Horseshoe crabs are one of the pioneers in using marine organisms to save human lives.
  69. Horseshoe crabs are what we have to thank for our flu shots.
  70. Horseshoe crabs are sometimes referred to as ‘man’s best friend’.
  71. Horseshoe crabs are often captured to have their blood drained, all in the name of science.
  72. Horseshoe crabs can be released after they have their blood drained.
  73. Horseshoe crab blood cells (amoebocytes) congeal and attach to harmful toxins produced by some types of gram negative bacterias.
  74. Limulus Amoebocyte Lysate (LAL) is the name of the clotting agent made using their blood to detect microbial pathogens in medical intravenous fluids, injectable drugs, and supplies.
  75. The global market for LAL is approximately $50 million per year.
  76. The adaptation for the ability of the horseshoe crab’s blood to congeal in the presence of either living or dead gram negative bacteria has never been able to be reproduced.
  77. Horseshoe crabs have used in the development of wound dressings and surgical sutures.
  78. Horseshoe crabs have a body shape that poses difficulty for predators.wireddotcom_drainblueblood
  79. Horseshoe crabs have ten eyes.
  80. The vision of a horseshoe crab is equally as impressive at night as it is during the day with the use of their lateral eyes.
  81. With a pair of compound eyes, each with 1,000 black disks, horseshoe crabs can see to each side, ahead, behind, and above.
  82. Scientists have learned quite a bit about how human eyes function from research with cells found in horseshoe crab eyes.
  83. Horseshoe crabs have a lateral inhibition mechanism using their eyes which allows them to distinguish mates in murky water.
  84. Horseshoe crabs need a book to breathe, that is – ‘book gills‘ to be more specific.
  85. Horseshoe crab gills have small flaps resembling the pages of a book.
  86. Horseshoe crabs tell time with their tail.
  87. Horseshoe crabs have a heart that cannot beat on its own.
  88. Horseshoe crabs eat through their brain.
  89. Horseshoe crabs chase females that run away!
  90. The black disks, also known as ‘ommatidia‘, found in the compound eyes of the horseshoe crab are the largest known retinal receptors in the animal kingdom.
  91. Horseshoe crabs are able to adapt to vast changes in salinity (i.e., they’re euryhaline).
  92. Horseshoe crabs are able to adapt to vast changes in oxygen availability (i.e., they’re euryoxic).
  93. Tracking juvenile horseshoe crabs with your eyes can be a great way to spend time at the beach.hsceyecloseup
  94. You can also track horseshoe crabs and other wildlife with your iPhone while at the beach.
  95. You can get involved in helping stranded horseshoe crabs and ‘Just flip ’em’ (see last picture).
  96. If you are a classroom teacher in Maryland you can raise horseshoe crabs as a way to increase student’s ocean literacy.
  97. Monitoring programs, like this one in Long Island Sound, are helping to advance the understanding of horseshoe crabs and their impact on humans.
  98. Development, pollution, water quality, and over harvesting have impaired the horseshoe crab’s habitat.
  99. Today and in the future we have the chance to protect horseshoe crab populations at a sustainable level for ecological and commercial uses.smilowitz
Filed Under: Atlantic Horseshoe Crab, Inspiration Tagged With: , , , ,

The world’s horseshoe crab research finally finds a home

January 16, 2013 by 1 Comment

This month the Ecological Research & Development Group (ERDG) released a one-stop-shop for research, conservation, and education initiatives on the world’s four species of horseshoe crabs. This was a result of the discussions from the 2011 International Workshop of the Science and Conservation of the Asian Horseshoe Crabs held in Hong Kong.

Be sure to check it out today. There’s lesson plans, peer-reviewed articles, posters, PowerPoint presentations, and more. It’s the intention of the database to serve as a tool to benefit everyone who is in Limulus Love!

I was surprised to learn that the new database includes over 2,000 citations and ERDG is still looking for more materials from people like you and me (Maybe, I’ll submit my cheesy infographic).

Horseshoe Crab Research Database http://horseshoecrab.org/research/

Horseshoe Crab Research Database created by the Ecological Research & Development Group

Filed Under: Atlantic Horseshoe Crab, Conservation, Environmental Education, Marine Science Tagged With: , , , ,

Jingle shells, jingle shells, jingle all the way

December 5, 2012 by 3 Comments

Oh, you know it’s stuck in your head. If not the Christmas carol, than the image of the beautiful shell that leaves a twinkle in the sand as you walk along the shoreline. Many people assume jingle shells are juvenile oysters because they’re often attached to them. But, jingle shells are their very own species known as Anomia simplex. Here are 10 facts for you to better get to know this treasured beachcomber’s find.

1. Jingle shells have thin, translucent shell halves that look like frosted nail polish.
2. Jingle shells have also been nicknamed “Mermaid’s Toenails”, “Saddle Oyster”, or  “gold shell”.
3. Jingle shells appear all year and are found in shallow waters, beaches, oyster beds, and mollusk shells as far north as the coast of Nova Scotia, and all the way down south to Brazil.
4. The jingle shell is a bivalve mollusk, similar to mussels, oysters, and scallops, which all have two separate shells or “valves”. The upper valve is rounded and movable. The lower valve is typically flat and forms to the object which it is attached. It has a hole in the top where tufts of filament, the animal’s byssal threads, grow out to attach it to another surface (i.e., Jingle shells are epifaunal just like bromeliads).
5. The raw meat of the jingle shell is sharply bitter to the taste.
6. The jingle shell can reach up to 1-3 inches.
7. The lower valve of the jingle shell remains white, while the upper valve ranges from shiny lemon yellow, golden, brownish, silvery black, or pale buff. The shiny iridescence of the jingle shell is retained even after death.
8. Jingle shells take in water and filter nutritious plankton and other food through ciliated gills.
9. Jingle shells were given their common name because of the sound they make when strung together. Beachcombers often use jingle shells to make jewelry or wind chimes. Julia Ellen Rogers noted in her 1931 The Shell Book that “Pretty lampshades are made by piercing the valves of jingle shells near the hinge and stringing them, then attaching the strands so as to fit over the outside of a plain glass or porcelain shade, whose brightness is pleasantly mellowed by the network of shells”.
10. Fishermen have been known to disperse jingle shells over oyster beds in a process known as “shelling” to create a habitat for oysters can settle.

jingleshells_mitchellspublicationsdotcom

 

 

Filed Under: Bivalves, Mollusks Tagged With: , , , , , ,

Do all horseshoe crabs molt?

November 20, 2012 by Leave a Comment
Once a horseshoe crab reaches their full size they stop molting. Their shells then come to host many sessile creatures, including slipper snails.

Once a horseshoe crab reaches their full size they stop molting. Their shells then come to host many sessile creatures, including slipper snails.

All horseshoe crabs molt – until they reach adulthood. They grow on average a quarter of their size each time they shed. Females grow to be about two feet across and males a bit smaller. Molting occurs several times during the first few years and slows as they age. It usually takes 17 molts to reach sexual maturity  at age 9-11.

Studies have proven that adults do not molt because the age of organisms living of the crab’s shell. For instance, scientists Bottom and Ropes (1988) completed a study to determine that large slipper snails (Crepidula fornicata) were at least 8 years old on a sample of specimens. This would then make the average age of horseshoe crabs in the Delaware Bay to be 17 years old.

Also, the deteriorated carapace of some horseshoe crabs, as well as the presence of internal chitinous rods that hold the carapace in place are also evidence that older horseshoe crabs do not molt.

Filed Under: Atlantic Horseshoe Crab, Environmental Education, Marine Science Tagged With: , , ,

New benthic species discovered off the coast of California

November 9, 2012 by 1 Comment

You might think all the animals that live in the ocean are floating throughout the sea, but there are entire communities of benthic animals and plants that live in a two-dimensional way just like we do on land. ‘Benthos’ are animals and plants that live in or on the ocean floor. These benthic animals live by one of three strategies: 1) attachment to a firm surface, 2) free movement on the ocean floor, 3) burrowing in the sediment. Sometimes a species may live by more than one of these strategies.

Recently, a newly described benthic animal was discovered in the deep-sea off the coast of California. Here is a video produced by the Monterrey Bay Aquarium and Research Institute of the carnivorous sponge, known as the harp sponge (Chondrocladia lyra).  It got the common name – harp – because the sponge has evolved up to 6 veins with structures fanning out from the spine to maximize ocean currents. The elaborate ribs have velcro-like hooks used to ensnare tiny prey and are also useful for distributing eggs. These animals use a rhizoid to anchor itself to the sea floor.

Filed Under: Invertebrates, Sponges Tagged With: , , , , ,

Well, well, ‘whelk’ what do you know?

November 7, 2012 by 6 Comments

It’s no surprise why my home state of New Jersey has been on my mind lately. Using my enthusiasm for nostalgia, I decided to investigate little known facts about the state. Today I am eager to share some at best ‘compelling’, but possibly ‘useless’ knowledge on the New Jersey’s state shell, the knobbed whelk.

Image (c) by Charles Tilford on Flickr: noncommercial use permitted with attribution / share alike.

Image (c) by Charles Tilford on Flickr:
noncommercial use permitted with attribution / share alike.

  1. Governor Christine Todd Whitman declared the knobbed whelk (Busycon carica) the state shell on April 13, 1995.
  2. In addition to being the state shell of New Jersey, the knobbed whelk is also the state shell of Georgia.
  3. The shell of the knobbed whelk is coiled and pear-like and appears anywhere from yellow to gray in adults with purple and browns tints in juveniles. Its inside is typically pink to white and iridescent.
  4. The animal that lives inside the shell is a one-footed member of the sea-snail family (specifically the family, Melongenidae).
  5. Knobbed whelks are found off the east coast of the U.S. from Massachusetts to northern Florida.
  6. The meat of the whelk (and that of the conch) is known as scungilli.
  7. Whelks have a large pair of tentacles, each with a light-sensitive eyespot.
  8. Whelks also have a small pair of tentacles that are used for smell and touch.
  9. The U.S. exports whelks (i.e., knobbed, as well as lightning) to many areas of the world including France, Southeast Asia, Australia, and the Caribbean.
  10. Horseshoe crabs are used as bait to harvest channeled or knobbed whelks.
  11. There is a popular Korean side dish known as golbaengimuchim, which is seasoned whelks with spicy sweet and sour sauce with vegetables.
  12. Knobbed whelks can be up to 12 inches long.
  13. Knobbed whelks and lightning whelks can be distinguished by the difference in their openings. Knobbed whelks are dextral (i.e. right-handed).
  14. Knobbed whelks and lightning whelks lay strings of egg capsules.
  15. Knobbed whelks feast on clams using a radula.
Filed Under: Mollusks, Univalves Tagged With: , ,

What happens if the tide leaves a horseshoe crab stranded?

November 5, 2012 by Leave a Comment

HSC_BCS

It’s not often you stumble across this on the beach. I asked horseshoe crab expert Danielle Chesky, Fishery Management Plan Coordinator with the Atlantic States Marine Fisheries Commission, what was happening in this picture and she said that “they’re dug in for the day after spawning until the high tide comes and they can get back out to sea”. For more posts on horseshoe crabs check out the Limulus Love page. Thank you to a colleague’s in-laws for sending along this picture.

 

Filed Under: Animal Homes, Atlantic Horseshoe Crab, Beach, Wrack Line Tagged With: , , , ,

Getting to know three … Bivalve edition

October 3, 2012 by 1 Comment

Ever know instinctively that some animals are ‘related’ and just can’t pinpoint their similarities? On the third day of every month I explain three features that are common among three animals of a certain group. Of course, generally each group has more than three representatives and even  many more similarities and then even more differences, but I am going to choose three similarities that link threes to keep it simplified. This month is focused the mussel, scallop, and clam. These three animals are all part of the bivalve group which is the second largest group of mollusks. The largest group of mollusks are the gastropods. Mollusks are well-known for their soft, unsegmented bodies and shell covering (although cephalopods do not have this feature). Check out the image below to learn what the featured animals all have in common.

Bivalves_BCS

 

 

Filed Under: Animal Homes, Beach, Biodiversity, Bivalves, Mollusks Tagged With: , , ,