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In this week's Ask Asta, we will explore Andrew's question; "What's the difference between shrimp and prawns, and how can you tell them apart?" Read on to find out! In the infamous movie Forrest Gump, Bubba said it best;" Shrimp is the fruit of the sea!" But what about prawns? How do they compare?  Image taken from Crosby.com This plate contains bite-sized, firm and tender morsels of undersea deliciousness. Imagine this has just been delivered to your table at a nice restaurant. I'll let you devour it, after you answer one simple question: Are these shrimp, or prawns? Why, you say, does that matter? Also, you say, why is Asta torturing me with food? Because we're imagining, silly. So, what's your answer?  Did you say that this was a lovely plate of Garlic grilled shrimp? Because if you did, you'd be wrong.
Or right. Depending on which country you're standing in. Have I confused you yet? Let me explain.
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In this weekly series, Asta answers your most unusual questions about the ocean. Got a good question? Ask Asta yourself! Email her at asta@Literasea.ca!  Photo from myinterestingfiles.com  Image from dailydawdle.com Have you ever taken a bubble bath? Bubble baths are my favorite way to relax. When I know my water is the right temperature and I've got enough water to warm up the tub, I pour soap into the stream of water from the tap. Seconds later, I have a bounty of bubbly foam to relax in! Is this the same kind of foam you see at the beach sometimes? It is similar, but the foam you see at the beach didn't come from soap and water running from a tap! In fact, tap or 'fresh' water and ocean water are very different. If you were to look at sea water under a microscope, you would see that every drop of seawater contains plenty of dissolved organic material, like decaying plants and animals, microplankton, salts, fats and proteins.  A single drop of sea water can contain all this.. imagine everything you touch when you go swimming! Photo from www.itsoktobesmart.com  Photo courtesy of Roger Edwards. These materials usually float in the water invisibly, and decrease the surface tension of the water, similar to the way soap does in the tub. In particularly rough weather, when the wind, waves and currents agitate sea water, tiny bubbles that form together in large quantities. These bubbles stick to each other due to their own surface tension, and this creates what we know as sea foam. Sea Foam, also known as Spume (my absolute FAVORITE new word!) is a natural phenomenon, and can be formed anywhere in the world. Usually, you will observe just a little foam, right at the water line between the ocean and the beach. However, Australia has had several incidences in which the entire beach, and even nearby beach towns, have been completely covered in sea foam! The amount of foam created is dependent on the level of wind, chop, and surfactant material in the sea water at the time. Sometimes, large sea foam events are linked to naturally occurring ocean processes, like phytoplankton blooms.  Is Sea Foam Dangerous? Just like in the bathtub, sea foam usually disappears after several hours or days. Most of the time, touching or interacting with sea foam is harmless to humans. However, not all sea foam is good sea foam. Sometimes, sea foam forms after contaminants have entered the marine environment. When crude oil, motor oil, detergents, or sewage build up in the marine environment, a smelly brown "chocolate mousse"-like sea foam can develop, and can be very persistent. You definitely would not want to bathe in that stuff! Sea foam can also be created after outbreaks of harmful algal blooms (from species such as dinoflaggellates or cyanobacteria) people to have respiratory (breathing) problems and skin irritation. A good rule of thumb is to enjoy the beauty of sea foam from afar if it's any color other than white!  Where have you seen Sea Foam?
Let us know where and when you've encountered sea foam, and what you think caused it! If you have a chance, you can even take a sample and look at it under a microscope. Leave your comments below! References: Atkins, J. 24/05/2009,"Warnings on sea foam on beaches" 702 ABC Sydney Article. Retrieved April 30, 2014. http://blogs.abc.net.au/nsw/2009/05/warnings-on-sea.html?site=sydney&program=north_coast_emergency Associated Press. "Raw: Sea Foam Blankets Australia Beach Town". Youtube Video. Retreived April 30, 2014. https://www.youtube.com/watch?v=-dvEmroCHXs Elert. E. 11/26.2012. "FYI: What is Sea Foam? Where does it come from?" Popular Science Article.http://www.popsci.com/science/article/2012-11/fyi-what-causes-sea-foam-and-it-dangerous Retrieved April 30, 2014. Innovateus Article. 2014. "What is Sea Foam?" Retrieved April 30, 2014. http://www.innovateus.net/science/what-sea-foam NOAA. January 29, 2013. "What is Sea Foam?"Retreived April 30, 2014. http://oceanservice.noaa.gov/facts/seafoam.html Life's Little Mysteries Staff. March 9, 2012. "How does Sea Foam form?". LiveScience Article. Retrieved April 30, 2014.http://www.livescience.com/33760-sea-foam-form.html Sharda. November 30, 2011. "What is Sea Foam and How is it Created?" Marine Insight Article. Retrieved April 30, 2014. http://www.marineinsight.com/marine/environment/what-is-sea-foam-and-how-it-is-formed/  Find out more about a dolphin's fins and a porpoise's purpose below! Dolphins and Porpoises may not seem all that different when you view them in the water. But if you look a little closer, you can notice some distinct differences between these two unique species. Both dolphins and porpoises originate from a lineage of of warm blooded, carnivorous ocean creatures, a lineage they share with whales, seals and sea lions in the order Cetacea (derived from the Greek word Ketos, meaning "large sea creature"). Both species also belong to the suborder Odontoceti, a group of animals known as the "toothed whales." Porpoises and dolphins share some common characteristics as well. They have similar body shapes, and often are found foraging and swimming in the same parts of the ocean. They are also both highly intelligent and use echolocation to interact with other members of their family or "pod" over large distances under water. When it comes to behavior, attitude and lifestyle, these two animals show some distinct differences. Check out how dolphins and porpoises compare in our "porpoise"ful comparisons chart!
 Photo Courtesy of wild whales.org. Video By Bioexpedition. Did you know… that both Porpoises and Dolphins can end up as prey for another species of Dolphin? The largest species of dolphin on the planet actually go by the name "Killer whale" or Orcinus Orca in fancy latin! Orcas are notoriously efficient team predators, meaning that they often work together to herd and hunt other marine mammals, like seals, sea lions and even porpoises and dolphins. Check out this amazing video of Pacific White Sided Dolphins being hunted by a hungry pod of Orcas! Video courtesy of youtube from 11MOAX.  References:
NOAA online. Last Updated March 14, 2014. "What's the difference between dolphins and porpoises?"Retrieved March 28 2014. http://oceanservice.noaa.gov/facts/dolphin_porpoise.html Wonderopolis."How Are Dolphins and Porpoises Different?"Retrieved March 28 2014. http://wonderopolis.org/wonder/whats-the-difference-between-dolphins-and-porpoises/ BC Cetacean Sightings Network. June 17, 2013. "Dolphin Vs. Porpoise: What's the Difference?" Retrieved March 28, 2014. http://wildwhales.org/2013/06/dolphin-vs-porpoise-whats-the-difference/ Diffen: Compare Anything Site. 2014. "Dolphin Vs. Porpoise." Retrieved March 28, 2014. http://www.diffen.com/difference/Dolphin_vs_Porpoise Dolphins World Online. 2014. "What is the Difference Between A Dolphin and A Porpoise?" Retreived April 2, 2014. http://www.diffen.com/difference/Dolphin_vs_Porpoise  Asta loves exploring and studying the exciting world under the sea. Each week, she will attempt to learn and answer her reader's most burning marine science questions, and provide some resources that help turn the question into a lesson plan! This weeks question comes from Ilan, age 5: "Do fish sleep? How?"  Fish may not curl up in a comfy bed like humans do, but they still make time for rest and refreshment. They can't get any shuteye though because fish don't have eyelids!
 A white tip slumber party! From DutchSharkSociety.org  Photo of a Zebrafish. Taken from Wikipedia commons.
There are still plenty of unanswered questions about fish sleep. Fish all seem to sleep slightly differently.
Maybe this would be a cool subject to research as a biologist! What do you think this knowledge could be useful for? References:
Asta loves exploring and studying the exciting world under the sea. Each week, she will attempt to learn and answer her reader's most burning marine science questions, and provide some resources that help turn the question into a lesson plan! This week, she delves into the world of the prickly pinnipeds, to answer a reader's question: "Why do Seals need Whiskers? What do they do with them?" -Sam, Age 10  Photo courtesy of http://www.cafeknaus.ch/sites/default/files/flying_burger.jpg Imagine this.... You come home from a busy day at school and your tummy's rumbling with hunger. You go into the kitchen to try and make your dinner, but the power's out and you can't see a thing! Worse yet, every time you grab for a bite of your favorite food, it zooms off away from you! What senses would you rely upon to relieve the rumble?  Photo courtesy of asknature.org. We may not have to worry too much about our food escaping from our refrigerator, but for the common harbour seal (also known as Phoca Vitulina), chasing their food in the dark is a pretty common problem. Harbour seals are members of the taxonomic clade "Pinnipedia". In Latin, this word means "feather or fin foot". This order includes 33 different types of marine mammals, but all of them share some characteristics, like long flat flippers, both at the front and rear of their bodies. Harbor seals are a member of the Phocidae family, also known as "true seals". They can be differentiated from other pinniped species by their lack of external ears, streamlined bodies and their long facial whiskers, known as mystacial vibrissae. Check out this great video from Lunchbox Lectures to learn more about the physiology of the Harbour Seal!  Are these cool? Photo From https://pbs.twimg.com
Harbour Seals don't just think whiskers look cool, like some humans do. They actually use their whiskers (also known as mystacial vibrissae) to receive tactile (touch) information from their surroundings. As harbor seals grow and mature into adulthood, they grow a series of long white hair like white bristles (called vibrissae) on either side of their noses. These long hairs are attached to the seal's muzzle, and are surrounded by motion sensing cells and nerves. The vibrissae have a "specialized undulated surface structure" which allows them to detect the speed and direction of water currents. The nerves attached to the vibrissae tell the seal's brain which direction a fish or animal might have moved through the water nearby by identifying its " hydrodynamic trail" (also known as a wake pattern.) Noticing an animals wake pattern can help seals discover another animal's direction, location, size, and other details about where the animal is going, and fast! This is really helpful info for a seal swimming in dark or noisy water.  A very cool study was conducted using a seal named Henry at the Marine Science Center in Germany recently (2011). A scientist called W. Hanke and his colleagues wanted to find out how seals used their vibrissa to hunt for prey, so they covered Henry's ears and eyes, and trained Henry to follow the trail of a variety of differently shaped fish tails. Even 35 seconds after motion had been created in the water, Henry could accurately track the movements of the tails, and was able to tell the types of tails apart!  Another interesting study last year showed that seals can actually use their vibrissae to measure the relative size of their food. Seals can judge the size of a fish based on the wake they leave as they move through the water, and decide between a bigger fish and a smaller one.
More than just a fashion statement, the harbour seal's whiskers help it survive! References: Bates, M. July 13, 2012. "Whiskers Seal the Deal."Psychology Today online. Retrieved February 6, 2014.http://www.psychologytoday.com/blog/animal-minds/201207/whiskers-seal-the-deal Hanke W, Witte M, Miersch L, Brede M, Oeffner J, Michael M, Hanke F, Leder A, Dehnhardt G. August 2010. "Harbor seal vibrissa morphology suppresses vortex-induced vibrations." Retrieved February 6, 2014. J Exp Biol;213(Pt 15):2665-72. doi: 10.1242/jeb.043216. Davies, E. 17 Feburary, 2013. "Seals judge size using their whiskers." BBC Nature article. Retrieved, February 6, 2014 from http://www.bbc.co.uk/nature/21442501 Daily Mail, 12 May 2011. "Harbor Seals use whiskers to detect fattest fish." Daily Mail Article.Retrieved February 6, 2014 from http://www.dailymail.co.uk/sciencetech/article-1386368/Harbour-seals-use-whiskers-detect-fattest-fish.html The Journal of Experimental Biology.May 16, 2011. "Seals sense shapes using their whiskers to feel wakes". ScienceDaily. Retrieved February 6, 2014 from www.sciencedaily.com/releases/2011/05/110512083141.htm  Clams are delicious, nutritious and fun to find at the beach, but did you know that they can also be detectives? These incredible bivalves can be used to help us find clues on how our environment becomes polluted, so that we can stop pollution where it starts, and protect our water sources!  How can an animal with no head, no arms and no legs tell us about the health of the ocean? Clams may have no way to communicate with us, but they certainly can be used to help indicate the health of the waters they live in. Clams are bivalve mollusks, meaning they have two hard shells protecting them from predators, held together by a hinge joint, ligaments and adductor muscles (for a great lesson on clam dissection, click here!). They mostly feed on phytoplankton, which they filter out from the water around them. Using their incurrent siphon, clams draw water into their protected shell palace. They then strain out organic particles from the incoming water using their gills, and sweep the food towards their mouth with the help of a layer of mucus. The water is then pushed out of clam's shell using the excurrent siphon. That's why you might see a clam squirt at you at the beach!  Clams are clever at filtering their food, but unfortunately they sometimes get more than what they bargained for. Along with their favorite phytoplankton, sometimes bivalves also pick up less desirable substances such as pesticides, lead, arsenic and PCB's (polychlorinated biphenyls). These pollutants accumulate in the delicate tissues of the clams, and are also traceable in their calcium carbonate shells. This process, known as bioaccumulation, is detrimental to the functioning of the clam, and also detrimental to the organisms that rely on clams for food- and that includes us.
Fortunately, scientists have found a way to use the cleaning power of clams to help indicate environmental pollution. Researchers are now placing clams in waterways and shorelines where pollution might be present. After several months of letting the animals grow and interact with the environment, scientists can retrieve the clams and conduct a chemical analysis on the clam's tissues. Using stable isotope techniques, the flesh of the clam can be analyzed to let the scientists know what kind of contaminants are present in that particular location. Not only will this research help us understand where chemicals are present, it may also help us determine their origin. Clams placed near rivers and industrialized coastlines, are compared to clams in other locations to see which locations are the most polluted. For more information on this type of research, check out the work of Dr. Ruth H. Carmichael and her colleagues at the Dauphin Island Sea Lab! It isn't just scientists that are using clams for detective work, students are also getting involved in the process! High school students in Washington are teaming up with Dr Harriette Phelps, Ph.D., a biologist at the University of the District of Columbia, to help understand how chemical contaminants are entering their local waters. Check out this great article from Science Today to learn about how they're doing it! It's pretty amazing that we can use filter feeders to help understand and mediate environmental impacts! For lesson plans on clams in the class room, check out: Clam Vocabulary from the Down East Institute for Applied Marine Research and Education: http://www.downeastinstitute.org/assets/files/Lesson%20Plans/Lesson%202/L%201-5%20%20word%20list.pdf Some cool clam crafts from about.com: http://homeschooling.about.com/od/unitssubjsci/qt/clamcrafts.htm A great comparative lesson for middle school students on clams and squid from Betterlesson.com: http://betterlesson.com/lesson/6946/compare-and-contrast-a-squid-and-a-clam References: American Geophysical Union. "Clam Cleanup-Biologists Clam up Waterways to Determine Sources of Pollution. Science Daily Journal Online Article. Published January 1, 2009. Retreived January 17, 2014. http://www.sciencedaily.com/videos/2009/0110-clam_cleanup.htm Biology Junction "Clam Dissection." Web article. http://www.biologyjunction.com/clam_dissection.htm Dauphin Island Sea Lab. "These Shells Don't Clam Up: Innovative Technique To Record Human Impact On Coastal Waters."ScienceDaily, 13 Dec. 2008. Web. http://www.sciencedaily.com/releases/2008/12/081202133226.htm Klappenbach, L. "Bivalves." About.com article. 2014. http://animals.about.com/od/molluscs/p/bivalves.htm  The holiday season is upon us, so we've decided to hand out some prezzies!
Every day for the next twelve days we will be posting a new marine creature with a photo and description! It's like a chocolate calendar filled with fish, crabs and strange creatures beyond your wildest dreams!... Okay, well that doesn't sound that appealing, but I'm sure you'll love all the photos that we took while volunteering at the Shaw Ocean Discovery Centre! Enjoy! The Twelve Days of Fish-Mas!  "The Water Brothers is an eco-adventure documentary series following brothers, Alex and Tyler Mifflin, as they explore the world, uncovering the most important water stories of our time." From the Water Brothers Website: The Series These guys came on board Sea Dragon to do ocean plastic research in the North Pacific Gyre. They made a sweet video about their experience. This video explains the issue very well with cool animations, interviews and more! "The Brothers embark on a sailing adventure to the middle of the Pacific Ocean to the remote “Great Pacific Garbage Patch”, a massive collection of plastic waste congregated together by swirling ocean currents known as gyres. What does the patch look like? How does it affect wildlife and the seafood we eat? Where in the world did this inconceivably massive amount of plastic come from and from what human activities, and more importantly, what can be done about it? The Water Brothers bring us some answers to this strange and disturbing phenomenon."
From the Water Brothers Website: Plastic Ocean  In this interesting article from Smithsonian Magazine author Joseph Stromberg examines a frightening phenomenon in which microplastic particles in the ocean are absorbing harmful chemicals. These chemical-laced plastic pieces are mistaken for food by fish and thereby the chemicals enter the food chain. The effects of bioaccumulation and biomagnification mean that the fish we eat may contain increased amounts of these toxins.
Researchers conducted controlled lab experiments with some troubling results: “We saw significantly greater concentrations of many toxic chemicals in the fish that were fed the plastic that had been in the ocean, compared to the fish that got either clean plastic or no plastic at all,” Rochman says. “So, is plastic a vector for these chemicals to transfer to fish or to our food chain? We’re now fairly confident that the answer is yes.” Read more: http://blogs.smithsonianmag.com/science/2013/11/how-plastic-pollution-can-carry-flame-retardants-into-your-sushi/#ixzz2mANYHCMw Follow us: @SmithsonianMag on Twitter  Asta's article in Marine Science Today has seen over 30,000 views in only a week! This amazing individual has accomplished a fantastic feat with her Masters Degree Internship with Pangaea Explorations! In December Asta will have earned her degree as a Master of Professional Science from the Rosenstiel School of Marine and Atmospheric Science (RSMAS). Check out thsi article about the work she did this summer.
Photo: Andrew Murgatroyd Link: Asta Mail: Citizen Science and an Expedition to the Great Lakes |
