12 truths about diamondback terrapins (please, see #8)

  1. Each diamondback terrapin is a work of art. Their skin color ranges from pale to dark gray, or even black. The underside of their shell (plastron) ranges from yellow to green, or even black. But, those variations aren’t the reason for its name. If have the opportunity, be sure to check out the mesmerizing diamond-shaped growth rings on top of their shell (carapace).
  2. normal_ian-symbol-malaclemys-centrata_iandotumcesdoteduDiamondback terrapins are native to the eastern and southern United States (just like me)! They are distributed from Cape Cod, Massachusetts to Corpus Christi, Texas.
  3. Diamondback terrapins have feet just like Ashton Kutcher. Their feet are robustly webbed, enabling them to be strong swimmers – which they need to be since they live in coastal areas with fluctuating tidal changes.
  4. There is only one terrapin native to the United States that lives exclusively in brackish saltwater marshes and bays … you guessed it, the Diamondback terrapin!
  5. Diamondback terrapins have a mid-life crisis at 20. They can live upwards to 40 years.
  6. Female diamondback terrapins are gladiators compared to the males. The shell of the females will reach up to 12 inches while the males typically reach 6 inches.
  7. Diamondback terrapins feast on meat. That’s right … they’ve only accidentally ingested vegetation (just like my 2yo).  They prefer to dine on blue crabs, snails, mussels, clams, barnacles, or whatever else in common in their range. They are pretty industrious in their ability to crush shells with their uber strong upper and lower jaw.
  8. Female diamondback terrapins might live in the marsh, but they prefer to lay their nests (2 to 3 a year with up to 20 eggs a clutch) on the sand beach from May to July. This is why you’ll often see female terrapins tentatively crossing causeways linking mainland and barrier islands. Please drive the speed limit and slow down (stop!) for nesting female diamondback terrapins. This is the most important fact in this list.
  9. Diamondback terrapins take time to meditate. Ok, well, they remain dormant and slow their metabolism down when they hibernate during the winter by burrowing in the mud of the marshes.
  10. Female terrapins like it hot. A higher temperature of the nest produces more females.
  11. After hatching, young terrapins take their time adapting to life. Some remain in the nest during the winter although the majority enters the nearest body of water.
  12. Habitat loss, boat/car strikes, nest predation (1 to 3% of the eggs laid produce a hatchling), and crab pots are all threats of diamondback terrapins.

Resources/additional information:
http://www.vims.edu/research/units/programs/sea_turtle/va_sea_turtles/terps.php
http://www.aqua.org/explore/animals/diamondback-terrapin
http://www.defenders.org/diamondback-terrapin/basic-facts

 

Nudibranchs: The elusive butterflies of the sea

The 3,000 species of nudibranchs (noo-duh-brangk) boast more colors than a box of Crayola crayons and most nudibranchs “live no more than a year and then disappear without a trace, their boneless, shell-less bodies leaving no record of their brief, brilliant lives”.

These sea slugs are found all over the world and range in size from a quarter of an inch to just about a foot. The word “nudibranch” means “naked gills”. A name appropriate since their gills are exposed prominently outside of their bodies (not covered like other sea slugs).

These gastropods are remarkable for their defense mechanisms. A listing and description of some are listed below along with some select images of these brilliantly colored sea slugs.

Warning coloration: Bright, contrasting pigments warn prospective predators they’re are inedible.
Skin: They can be can be tough-skinned, bumpy, and abrasive.
Toxic secretions: Some feast on poisonous sponges and then absorb the toxins into their body which are secreted later when disturbed.
Stinging cells: Some accumulate the stinging cells (nemocysts) from their prey (e.g., fire corals, anemones, and hydroids) and then the stinging cells are emanated from their own body when distributed.

http://kids.nationalgeographic.com/kids/photos/strange-underwater-creatures/

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nudi3

Nudi4

Nudi5

I must admit that the title and inspiration of this post came from the book “The Highest Tide” (2005) by Jim Lynch. If you have time this summer it’s a must read if you think you might enjoy an homage to Rachel Carson secretly embedded in a coming of age story set along the coast of Puget Sound.

Image (c) top to bottom:

http://kids.nationalgeographic.com/kids/photos/strange-underwater-creatures/http://oceanexplorer.noaa.gov/explorations/05deepcorals/background/chemical_ecology/media/nudibranchs.htmlhttp://www.nsf.gov/news/mmg/mmg_disp.cfm?med_id=71085http://www.nationalgeographic.com/wallpaper/ocean/photos/nudibranchs/nudibranchs02-tritonia/http://photography.nationalgeographic.com/photography/photo-of-the-day/spanish-dancer-nudibranch/

Horseshoe Crab Round Up: May 2013

And, we’re concluding the first month of the horseshoe crab mating season for 2013. Over the past couple of weeks, many articles have come through the great worldwide web including some new creative introductions on the relationship of Limulus polyphemus and shorebirds, captivating expose on the capture of two horseshoe crab poachers, updates on the plight of the species after Hurricane Sandy, the discovery of a new bait that could reduce the horseshoe crab harvest, and even a information on raising awareness of the role horseshoe crabs since they play a role with QC endotoxin detection tests (but, read more to see that there may be a sustainable alternative). If you have anything other interesting reads for May please post a comment below.

Limulus polyphemus and Shorebirds (including efforts on tagging, etc)
Journey of shorebirds, horseshoe crabs to shore linked through the ages – May 1, 2013
Protecting ancient undersea creatures – May 9, 2013
Being ‘crabby’ might benefit mankind – May 10, 2013
Tagged Horseshoe Crabs at Big Egg Marsh Queens NY… – May 25, 2013
Shorebirds, Horseshoe Crabs and Stewards… – May 26, 2013
Volunteers help tag mating horseshoe crabs on Harbor Island – May 28, 2013

 

The Poaching Adventure
2 arrested for poaching horseshoe crabs from NY – May 28, 2013
It’s Dark, but We See You: Release the Horseshoe Crabs – May 28, 2013
NYPD Busts Horseshoe Crabs Poachers After Chopper Chase – May 29, 2013

After Hurricane Sandy Habitat Restoration
Restoring hurricane-damaged horseshoe crab spawning beaches on Delaware Bay – May 11, 2013
Workers race nature to rebuild Shore habitats before mating, migration season – May 20, 2013
After Sandy, a race against time to save an endangered shorebird – May 25, 2013

New Bait Alternative for Eel and Whelk
New bait may cut horseshoe crab bait use – May 30, 2013
New artificial bait could reduce number of horseshoe crabs used to catch eel, whelk – May 30, 2013

QC Endotoxin Detection Tests
Lonza Not ‘Shellfish’ When it Comes to Endotoxin QC Testing – May 21, 2013

Guest post: Cherilyn Jose of Ocean of Hope (where “Marine Animals Voice Their Wishes”)

I was honored she Cherilyn Jose asked if I could do a guest post for her, but not too shy that I didn’t ask her to reciprocate (I love the information she puts out there on her blog so I thought it was worth a chance!). She kindly did so, and am I ever thrilled! Here’s a bit of background on her and some prose on a favorite West coast species of her’s – the Dungeness crab.

Cherilyn Jose blogs at Ocean of Hope: Marine Animals Voice Their Wishes. She is a marine biologist, writer, and nature and underwater photographer. She is also an avid SCUBA diver and home aquarist. She asked me to do a post for her, but I told her … “only if you reciprocate”, and she kindly did so!dungenesscrab

Help! It’s Dungeness crab (pictured right) season here off of California, Oregon, and Washington. California’s crab season runs from November to June. Unlike many other ocean species that are in decline due to overfishing, Dungeness crabs are not in short supply. It may be due to females producing up to two million eggs at a time. I passed through 6 larval stages before becoming an adult and settling on the sandy or muddy seafloor.

The abundance of Dungeness crabs may also be due to my food preference, or lack thereof. I am a scavenger and I will eat, well, anything edible I come across. There is an increasing amount of plastic in the ocean, and I unfortunately can’t tell the difference between that and my real food sometimes. Plastic can be large like plastic grocery bags, or small like the microplastics that start at the bottom of the food chain and insidiously work themselves up into the bodies of top-level predators. Did you know that you carry several pounds of plastic in your body?

It is so tempting to get the “free” food from the crab traps and hoop nets, but I wouldn’t be alive today if I didn’t pass them up on a regular basis. It doesn’t help me that SCUBA divers are allowed to take us by hand while diving too.

Fortunately females are not allowed to be taken, as well as any crabs that are too small. Those crabs that are tossed back ensure another generation of crabs ends up on some human’s dinner plate. In the meantime, I’ll play the odds that I will survive another day past June-after all my lifespan can be up to 8 years!

 

What I know about whale sharks

Sure, you know that whale sharks are the largest fish in the sea (reaching up to 42 feet) and they sieve plankton for nourishment. Being that you’re clever and smart you must know these ten wicked facts about whales sharks, too – but, I’ll tell you again anyway.

  1. Whale-Shark-03Whales sharks have the thickest skin in the world – just about 10 centimeters thick!
  2. Whale sharks may have wide mouths for gulping plankton, but don’t worry – they can’t swallow a diver as their throats are exceptionally narrow in comparison to their mouths.
  3. Whale sharks don’t just eat plankton, they sometimes wait for fish to lay their eggs so they can eat those, too.
  4. In Vietnam, whale sharks are known as Ca ong, or “Sir Fish”.
  5. The whale shark was once worshiped in Vietnam, and along the coast you can still find ancient shrines along the coast.
  6. Whale sharks are covered with pale stripes and spots (see image).
  7. “What’s that bump?” Whale sharks attempt to get rid of skin parasites by rubbing themselves up against boats.
  8. Whales sharks are loners. They prefer to live, hunt, and travel alone.
  9. Most sharks live to be around 25 to 30 years old, however whales sharks and dogfish sharks can live to be 100 years or more!
  10. Whale sharks are thought to be able to give birth up to 300 pups at one time.

3 truths on the fables about ‘dolphin-safe’ labels

It all started recently as my 2 year-old showed those tendencies towards becoming a picky eater. I embarked on a supermarket safari for proteins and soon enough I found myself in the canned tuna aisle. Have you been there lately? It’s a little overwhelming with all of the labels. I usually just go for the salmon for the additional omega-3s, but I had a feeling the toddler would turn that down. Also, I am all about rites of passage and isn’t canned tuna with mayonnaise on toast right up there with peanut butter and jelly and macaroni and cheese? Given that I do care, especially with the recent findings of an Oceana report that states 1 in 3 fish are mislabeled,  the nerd in me had to navigate the meaning behind all those ‘eco-safe’ labels found on canned tuna.

Here’s some surprising truths behind the fables about the ‘dolphin-safe’ label you’ll need to know before baking your next casserole:

1) The U.S. wouldn’t sell anything that’s not ‘dolphin-safe’ – label or not. While it’s true that the U.S. has the most restrictive definition of what it means to be ‘dolphin-safe’ it’s also true that canned tuna is the #1 seafood import in the U.S. The internationally accepted definition of ‘dolphin-safe’ is “tuna caught in sets in which dolphins are not killed or seriously injured,” but the U.S. requires that “no tuna were caught on the trip in which such tuna were harvested using a purse seine net intentionally deployed on or to encircle dolphins, and that no dolphins were killed or seriously injured in the sets in which the tuna were caught.” Unfortunately, if we’re rarely eating tuna from the U.S. we can’t say how it’s caught.

2) ‘Dolphin-safe’ labels are designated by the government. I was shocked to realize that its independent observers (i.e., private organizations) making claims to what is ‘dolphin-safe’. But, then I remembered that tuna are an especially difficult species to manage given that they migrate all over the world. The good news on the horizon is that during his State of the Union address in January, President Obama mentioned the U.S. will begin negotiating a free trade agreement (FTA) with the European Union. What does this have to do with tuna fisheries? Well, apparently the talks for the FTA would include discussions on non-tariff barriers. Non-tariff barriers include “things like labels indicating a product’s country-of-origin, whether tuna is dolphin-safe, or whether your breakfast cereal has genetically-modified corn in it.” The need to be more consistent as to how we label tuna was also acknowledged by the World Trade Organization (WTO). The WTO noted that, “while well-intentioned, the ‘dolphin-safe’ labels are deceptive to consumers and quite outdated”. Also, according to the Campaign for Eco-Safe Tuna, “There’s no denying that more than 98% of the tuna in the U.S. market today is sourced from unmonitored and untracked fisheries where thousands of dolphins are killed every year.” That’s a frightening statistic if you’re trying to make the right choice on what can of tuna to purchase.

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Image (c) World Wildlife Fund

3) If it’s ‘dolphin-safe’ it must be safe for all marine life. Let’s cut to the chase here. Canned tuna that is troll or hook-and-line caught with fishing rod and reel combos is the best choice for a conscious consumer. Other methods of fishing for tuna (e.g., backdown technique, purse seines) have been shown to cause long-term stress to dolphins (leading to their eventual death), including heart and muscle lesions. You might also be disheartened to realize that sharks, billfish, birds, and sea turtles (see image) are often the unintended catch (known as ‘bycatch’) of fishing for tuna. The fish aggregating devices (FAD) commonly used to catch tuna are known as some as the most destructive fishing practices man has ever used.

Where does that leave me in the decision of what type of tuna to purchase for my family? As I mentioned, choosing hook and line (also known as ‘pole-caught’) canned tuna is the most sustainable choice. Fishing for tuna with hook and line 1) enables fish that are too small to be returned to the ocean, 2) practically eradicates any bycatch, and 3) ensures the ocean ecosystem to remain intact eliminating the potential loss of biodiversity. Be careful though since ‘line-caught’ can mean using a longline to catch tuna. However, this method produces ample bycatch as well.

Please feel free to comment below or email questions on this article to Ann McElhatton, Beach Chair Scientist, at info@beachchairscientist.com.

A Scientist’s Inspiration

Ryan K Morris/National Science & Technology Medals Foundation.

Ryan K Morris/National Science & Technology Medals Foundation.

For Dr. Penny Chisholm, a single look into the microscope as an undergraduate student set off a chain of events that led to a lifetime of work, important new research changing our understanding of the oceans and, just recently, an honor from President Obama at the White House.

The Lee and Gerldine Martin Professor of Environmental Studies at the Massachusetts Institute of Technology (MIT), Dr. Chisholm recently shared her thoughts with Beach Chair Scientist on her recent National Medal of Science Award and her research work. She also discusses her work as children’s book author, even sharing her cure for writer’s block.

BCS: You described your recent National Medal of Science Award as a high point of your career and a thrill – something you probably couldn’t have imagined when you were an undergraduate. What first sparked your interest in microbial oceanography?
CHISHOLM: I first viewed phytoplankton under a microscope as an undergraduate at Skidmore College.  I found them beautiful and fascinating.  After a few detours, my studies in graduate school focused on a single species of phytoplankton called Euglena, which is one of the “lab rats” among the phytoplankton. I used it to begin to understand (literally) how these cells get through their day.  But I soon realized that the oceans held enormous challenges and studying them would broaden my horizons. So I sought a post-doc at Scripps Oceanographic Institution to where I studied phytoplankton in the wild.

BCS: After receiving word of your award, you told the MIT newspaper that the honor was particularly gratifying because Phytoplankton had been under-noticed despite being the base of the ocean’s foodweb. That said, what has the medal meant to you in terms of the exposure both for the marine microbiology field and for your research?
CHISHOLM: The Medal came as a complete surprise.  It is not something that is common in my field as it is relatively small compared to some others that are highly represented among the Medalists.  I feel that I accepted the award on behalf of the many oceanographers who have pushed our field forward in leaps and bounds over the past decade.  In addition, the Gordon and Betty Moore Foundation has generously funded Marine Microbiology for the past 8 years, which has made a tremendous difference in what we have been able to discover.

BCS: For those of us who aren’t in the field, what should we know about this microorganism and why is it so important in helping us get a better understanding of our planet?
CHISHOLM: Phytoplankton are microscopic plants that form the base of the food chain in lakes and oceans. Through photosynthesis- in which they use the sun’s energy to build organic carbon (living matter) from carbon dioxide gas drawn from the air –  they produce the food for all of the other organisms in the ecosystem, from small zooplankton on up to fish. They draw as much CO2 out of the atmosphere each year, and produce as much oxygen, as all the plants on land.  As such they play an important role in balancing the global carbon cycle, which in turn has an influence on Earth’s climate.

My research for the past 25 years has been on a single species of phytoplankton called Prochlorococcus. It is the smallest and most abundant photosynthetic cell on Earth, and is responsible for a sizable fraction of photosynthesis in the oceans.

BCS: Were there any particular people – in or out of science — who helped and encouraged your interest in science at an early age? How so? What’s your message to young people considering getting into the field today?
CHISHOLM: My interest in science grew slowly as I went through school.  I think the most significant step was when my undergraduate advisor at Skidmore College mentioned to me that I could get a PhD if I wanted to. It had never occurred to me.  I loved studying, so that sounded a lot better than getting a job after I graduated.  I was also drawn to science as a “way of knowing”.  I remember being impressed by the idea that you could make measurements and do experiments, and write the results up in a publication and people would believe you.  I think I found appealing the idea of science as a platform for being heard.  Perhaps growing up in the ’50s- when women’s voices did not carry much weight – influenced me in that regard.

BCS: You’re also the author of two children’s books. What if any similarities exist in your work as an author and as a scientist?
CHISHOLM: Working on the children’s books has helped me learn how to boil concepts down to their very essence.  The truth is that we made these books with the hope that not only children, but parents and teachers would learn from them.  The books, which are narrated by the Sun, cover some very fundamental concepts about life on Earth and our dependency on plants and photosynthesis,  that most people do not understand.  I believe that if we all share this understanding, along with a sense of awe about life on our planet, we will have more respect for all of life on Earth and our dependency on it.

BCS: What’s next for you as a writer?
CHISHOLM: I have a few things on my plate.  The most immediate is third children’s book with Molly Bang, called “Buried Sunlight”.  It is about fossil fuels, how they were made over the history of the Earth, and how burning them in a few hundred years time is changing the planet.

BCS: Do scientists get writers block, too – if so, how do you tackle it?
CHISHOLM: Of course!  What I do is go for a walk.  That usually removes the block, and, more importantly, opens new channels.

To learn more about Dr. Chisholm’s research, visit http://chisholmlab.mit.edu, and see her children’s books, Living Sunlight: How Plants Bring Earth to Life and Living Sunlight: How Tiny Plants Feed the Seas.

Molly Malone’s cockles and mussels

On the way home from work yesterday I had a driveway moment and could not stop listening to a story on All Things Considered on the benefits of forgoing the pub this Sunday and instead preparing some heartwarming Irish food at home to celebrate Erin go bragh. The story featured a recipe – Molly Malone’s Cockle and Mussel Chowder – from Rachel Allen, a popular Irish TV Chef, and I got to thinking on how I think it’s time to briefly feature those bivalves on Beach Chair Scientist! Here are 5 facts about cockles and mussels so you can have some fodder if you like to pretend to be the host of a show while cooking for your family.

Cockles

Cockle shells

Cockle shells

  1. There are more than 200 species of cockles.
  2. Cockles have a distinct rounded, heart-shaped shell with ribs that fan out through the length of the shell (they’re actually evenly spaced on the exterior of the shell).
  3. Cockles prefer intertidal areas with sand and mud beaches and depths up to 60 feet. Cockles are distributed world-wide, but the common cockle (Cerastoderma edule) is found widely distributed around the coastlines of Northern Europe (extending west to Ireland, the Barents Sea in the north, Norway in the east, and as far south as Senegal).
  4. Cockles move with a powerful muscular foot. They’ve even been witnessed springing with this strong foot on the bottom of the ocean floor.
  5. Cockles are not important commercially.

Mussels

mussels_wired

Mussel shells

  1. Mussels have wedged-shaped, asymmetrical shell that is longer than wide. They’re typically dark blue, blackish, or brown, while the interior is silvery and somewhat nacreous.
  2. Mussels are filter feeders and feed on plankton and other microscopic, free-floating sea creatures in seawater.
  3. Mussels provide shelter and protection from heat, desiccation, and predators for many smaller marine organisms.
  4. According to Wired, “Chemists recently made prototype bandages with an inkjet printer filled with adhesive proteins taken from mussels, whose remarkable “feet” — a tangle of fibers that anchor them to rocks — have made them the most widely studied specialist in marine clinging”.
  5. 90% of the world’s mussels are cultured, with the major producers being China, Spain, Italy, Thailand, France, and New Zealand. Don’t fret, the U.S. has tough regulations on its imports of mussels.

Click here for the lyrics to the Irish song Cockles and Mussels, or Molly Malone. Erin go bragh!

17 facts about the wee sea potatoes

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

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The test of the sea potato

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The underside of the sea potato

CITES recognizes important marine species

You might think that sharks are a predator that we want to eradicate, but that’s far from the truth of the matter. For a healthy ocean we need the top predator. For 5 species of sharks – oceanic whitetip, scalloped hammerhead (pictured below), great hammerhead, smooth hammerhead, and porbeagle sharks – there was some inspiring news during the 16th meeting of the Conference of the Parties for the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES). Proposals were adopted that would give them greater protection and provide them with less risk from overfishing (According to the Guardian, “Those fishing for oceanic whitetip, porbeagle and three species of hammerhead shark will now require strictly controlled permits to export the fins”) for these sharks. However, the move will need to be adopted completely by a final plenary session scheduled for Thursday. It’s a particularly significant move considering CITES meetings take place every three years and that CITES has not traditionally leaned towards protecting marine species due to the intense political and economic issues that are related to fisheries issues. According to the Washington Post, “Elizabeth Wilson, who manages the Pew Environment Group’s global shark campaign, said the broad array of countries backing the proposals this year helped produce success this time around”.

Globally,  sharks are in peril and overexploited due in major part to a voracious demand for shark fins, especially in Asian markets, since it’s the primary ingredient in shark fin soup (more affordable and more popular than ever at Asian weddings). While it might be a difficult culture shift for the expanding Asian middle class (a delegate at CITES stated, “It would be like telling the French not to have champagne at their wedding“), ultimately it’s what has to be done since shark populations have fallen to such low levels. As they saw off the coast of North Carolina once sharks were overfished rays thrived and then destroyed the lucrative bay scallop fishery. Here is another resource outlining the importance of sharks to the ocean ecosystem.

Scalloped hammerhead shark (sphyrna lewini)

Scalloped hammerhead shark (sphyrna lewini) from NatGeoTV