Good Bacteria Turns Bad

This article ties in with the presentation that i will be presenting on next week. Coral bleaching is the whitening of coral, from the loss of their symbiont. Coral bleaching is an increasing problem due to the increased water temperatures. Coral reefs are very important to the human economy and to a vast diversity of animals.

This article talks about the bacteria that live on coral reefs, in normal conditions these bacteria produce a mucus layer that protects the corals. This mucus layer prevents the corals from getting infections from bacteria. However, with the increasing temperature of the water the mucus layer breaks down and the good bacteria are replaced with pathogenic (bad) bacteria. This model has also shown that once the water temperatures return to normal the pathogenic bacteria remain on the corals. The mechanism is not quite understood to explain the pathogenic bacteria remaining on the corals when temperatures return to normal. The water temperatures have been increasing over the past years and many steps need to be taken to improve coral reef habitats before they are lost forever.

Good Bacteria Turns Bad

Loggerheads Unveiled

 Loggerhead turtles are currently a threatened species. However, these turtles on the verge of becoming endangered and are appearing in decreasing numbers. Research by a team of University of Florida biologists from the Archie Carr Center for Sea Turtle Research shows that turtles are unique. The turtles live and eat where they please, but surprisingly they do not eat or live in large numbers. Loggerhead turtles are known to be extensive travelers. They can swim thousands of miles and eat many different bottom-dwelling species such as crab and whelks. However. research has shown that the turtles chose what they eat and prey mostly on what they prefer to eat. The research also has shown that individual turtles stay within a certain range and do not travel far away from the place they make home. The researchers know this because they biopsied fifteen female loggerhead turtles. The removed tissue was observed using mass spectrometry.  The readings showed different densities that correlated with what they ate and where they were living.  The research followed the turtles for a twelve year time span. Future research is being conducted to help predict where the turtles will live and what they will eat. The research then can be used to protect the turtles and help their population size increase.

Are marine microbes our answer to plastic pollution?

Microbes are the most numerous of marine organisms, and recent studies are underway to see just how these organisms interact with plastics in the ocean. Plastic pollution is a big problem, because in the environment, it can take thousands of years to break down. Over time, the size of plastic decreases in the ocean because of natural forces wearing on it. The tiny fragments are dangerous because they can absorb toxins that can be ingested by marine animals. Researchers at the University of Sheffield and the Center for Environment, Fisheries, and Aquaculture science are providing evidence that the type of microbes that grow on these plastic fragments significantly varies from the microbial groups that colonize the wider environments. These microbes may be contributing to the breakdown of plastic pollution and toxins in the marine environment. Using DNA experiments, these researchers are finding that plastic is quickly colonized by many species of bacteria that together form a biofilm along the plastic surface. This biofilm is only formed by certain types of marine bacteria. It's going to take more research to fully understand the impact these bacteria have on plastic pollution, but these experiments could offer insight into the impacts of plastic pollution on the global environment.
Picture from: http://www.surfrider.org/kauai/SR_Kauai/RiseAbovePlastics_files/Snapshot%202008-04-14%2016-30-34.jpg

Barnacles enriching the trophic dynamics of the Galapagos waters

Researchers debate what happens to key sources of food during strong upwelling currents. As we learned in class, a strong upwelling can carry larvae from organisms like barnacles from their offshore home out to sea where they would die.

New Research shows that barnacles, a key food source in fact thrive in strong upwellings. When a strong upwelling is present the barnacle larvae is more likely to be recruited to the rocky walls. When this happens the predators of the barnacles, like hogfish and whelks flock to these strong upwelling zones creating dynamic ecosystems where there were thought to be none.

Several studies have shown that strong upwelling zones aren't good environments for barnacles to live and have shown this before. The new research was done in deeper waters and the research was done by one of the only teams to be working in these waters in the Galapagos Islands.

To learn more click here

Giant crocodile in the United States

Recent studies have been done on the ancient giant crocodile Deinosuchus. Deinosuchus can grow to 29 feet long and can eat dinosaurs as large as them. This current study has been analyzing the jaw and fossilized crocodile dung, some of these specimens are from Georgia.It is predicted that these giant crocodiles fed on dinosaurs and large sea turtles.

Professor Schwimmer and his student Harrell believe dinosaurs were the main diet and preferred food; these conclusions were drawn based on the jaw size, teeth markings on dinosaur bones, and the evidence found in the fossilized dung. The evidence supporting this are the Deinosuchus teeth marks in the bones of dinosaurs found in many different locations in North America

The dung that was analyzed showed many shell fragments and sand particles; this led to the determination that they live in shallow marine waters. Schwimmer and Harrell recently presented their finding in many locations in the US.

Giant crocodile in the United States

Are Bioluminescent Bacteria Behind Milky Seas Legend?

For several Centuries, sailors have told stories of so called "milky seas." These 'milky seas' seemed to be glowing a dim white light. According to the log of the S.S. Lima as it sailed off the coast of Somalia 11 years ago, they were surrounded by waters that appeared as a field of snow or clouds in all directions. Scientist have been able to go back and look at satellite pictures at the time of this voyage and were able to find pictures confirming the glowing sea. Scientist say that this glow is caused by bioluminescent bacteria. One might ask how many bioluminescent bacteria would it take to light up the seas? Well if one were to cover the earth in a 4 inch layer of sand and then count all of the individual grains of sand in that layer, thats how many it would take. These glowing seas typically only last a few days are usually found in the Indian Ocean.

Scientist hypothesize that the bacterium Vibrio harveyi is responsible for this bioluminescence. There are dinoflagellates that will give off light as well. These organisms however must be physically stimulated to produce a brief flash of light. V. harveyi seem to give off a continuous light on their own. One hypothesis that is mentioned for the bacterium to continuously glow is to attract fish so they can enter their guts and live there.

The article and a minute long video can be found here.

Seaweed the New Diet Fad?

With obesity on the rise in America, American's are looking for alternatives to diet and exercise. According to Dr Iain Brownlee and Prof Jeff Pearson of Newcastle University,  naturally occurring seaweed may help reduce the amount off fat that is absorbed by the body. The seaweed contains a natural source of dietary fiber called Alginate that helps reduce the amount of fat that is absorbed by the body. The Alginate has been scientifically proven to reduce the amount of fat absorbed by the body than current over the counter treatments available right now. According to the test, the seaweed tests better than white bread and may prevent 75% of the fat eaten during that meal from being absorbed by the body. According to researchers at Sheffield Hallam University, a different type of seaweed can be used instead of salt in preserved foods. This would help decrease the excess salt that is consumed by humans. This could ultimately help reduce future heart problems caused by excessive salt intake. Whether your looking to lose weight or protect your heart, seaweed may be the answer for a healthier lifestyle.

These articles can be found on Sciencedaily:  

     http://www.sciencedaily.com/releases/2010/03/100321203508.htm
     http://www.sciencedaily.com/releases/2008/09/080919075129.htm

Sea urchin growth

Researchers Amy Johnson and Olaf Ellers are studying how sea urchins (and echinoderms in general) can grow. Somehow, they can do it without having to shed their shells or skeletal plates.

They discovered that as urchins grow, the collagenous tissue inside, outside, and between their skeletal plates softens. The shell inflates like a balloon. The collagen stretches and expands gaps between the plates from the inside, while containing them from the outside. Eventually, the tissue between the plates is reabsorbed and is replaced by hard shell. This mechanism is similar to the growth of a vertebrate skull. [1]

Scientists want to use this information to make “sea farms” of sea urchins possible. Only two experimental hatcheries are in use right now: a commercial one in Lubec, Maine, and another developed by the University of New Hampshire. If they are successful, they could “seed” areas overharvested for sea urchins to restore their populations. (Sea urchins are a delicacy in Japan. In 1993, 30 to 40 million pounds were harvested.)

They are still looking into what makes sea urchins reproduce, grow, and thrive. This research is complicated by the fact that it takes sea urchins six years to reach sexual maturity.
Right now they aren’t sure yet if sea urchin sea farms would be economically viable.

[1] Bowdoin Researchers Seek Methods to Spur Sea Urchin Growth
http://www.bowdoin.edu/news/archives/biology/000222.shtml

Sea urchins may see with their feet

Check out this timely new post from Creaturecast on how sea urchins use photoreceptors all over their body to form visual images.  There are also some nice photos of tube feet.

It points out how much more there is to learn about common marine organisms, simply because no-one has thought to look.

Oyster Reefs Invaded

The Olympian Oyster, commonly found on Tomales Bay in California, has begun to vanish due to humans moving certains species beyond their natural borders and habitats. Native and exotic species relationships may have an effort on the loss of critical habitats due to this discovery. David L. Kimbo, marine biologist and his colleagues from The Florida State University Coastal and Marine Laboratory are responsible for this discovery. The loss of this Olympian Oyster will be dramatic because they provide many settlement habitats for different species. With this study, the habitat management and conservation efforts in Florida will be more successful to help restore the oysters. The Atlantic Coast crabs and snails are the explanation for this oyster decline because of the predator-prey mismatch. The native and non native species being introduced has caused the oyster habitat to become interrupted, which has lead to decline. Kimbo and his team are planning to keep studying this interaction to try and protect those Olympian oysters.

• Reading the full article will give a more detailed explanation of this oyster decline.

Olympian Oysters

• Picture shows the Intertidal Zone of Tomales Bay in California, the oysters are present on the rocks.

Scientists find evidence of hyrothermal vents off of the coast of Antarctica

In the past several decades, more than 220 hydrothermal vents have been found around the world. Up until recently, no one has ever looked for them in the freezing cold waters of Antarctica. Hydrothermal vents are known for releasing volcanically heated water from deep within the planets underwater mountain ranges. The chemicals found in these vents are known to influence the biodiversity and chemistry of the ocean, much like sunlight on land. By analyzing thousands of oceanographic measurements, a team of scientists were able to place six hypothetical vents on the Pacific Antarctic ridge. These vents were pinpointed using two important facts; 1) they are areas where the ocean is stratified with layers of lighter water sitting on top of denser water, 2) when a seafloor vent erupts, it releases gases rich in Helium-3, which mixes with ocean water and stays within a density layer that forms a plume that can stretch thousands of miles. When these scientists were analyzing Helium-3 content in the water, they came across a random plume in the southern portion of the Pacific Ocean. This plume was located below a well known plume coming from the East Pacific Rise. But the new plume was too deep to have the same source. Using approximately 25,000 salinity, temperature and depth measurements, the researchers compiled a map of ocean density layers in that region. They located the plume along a single density layer and compared that layer to the topographic map of the region to find out where the plume would intersect. The sites they identified cover 340 miles of ridge line with a chain of volcanic mountains that lies about 3 miles below the oceans surface. They haven't found the vents, but they have narrowed down the places they could look. The map that these scientist created will be helpful in narrowing down the search sites. Once they are within a few kilometers of the vent, they will be able to detect the rich minerals flowing out of it. Study of the vents on the Pacific Atlantic Ridge will offer valuable insight into how the biodiversity varies between the Pacific and Indian Oceans.

Radulas and oysters

After talking about the various lethal things that gastropods do with their radulas, I thought you might like this post from the Deep Sea News.

And check out this video on the blue crab fishery in North Carolina:

Types of breakers

I got this on a bit late, but check it out if you have time before class on Monday.

Sea squirts that may be able to cure Alzheimer's

Alzheimer's disease is the most common form of dementia, the most feared age related disease. There is no cure only drugs that can slow the affects. The key to curing the disease is the removal of the plaque build up in the brain.

Researchers from the university of San Diego have found a sea squirt that may hold the key to curing this disease; the sea squirt Ciona intestinalis. While not actually being able to cure any disease through some magical protein the sea squirt is the humans closest invertebrate relative and shares 80% of its DNA with humans making it an amazing model for DNA studies with its ability to incorporate foreign DNA.

This Sea squirt can exhibit the traits of someone with Alzheimer's disease if given the DNA of someone with the disease to incorporate into themselves. While not being able to cure the disease the sea squirt gives us the next best thing; a model to quickly and effectively study Alzheimer's.

For more information click here

Humpback Whales to the Rescue

Allomaternal care (maternal care provided by an individual towards offspring other than one’s own) has been demonstrated by numerous species however, more recent observations now include humpback whales.

The NOAA Fisheries Service expedition, which first observed this behavior, was sailing from South America to the Antarctica Peninsula in search of killer whales and recording their hunting tactics. A main component of a killer whale’s diet is Weddell seals. Researchers aboard the vessel, Robert Pitman and John Durban, were shocked as they watched ten killer whales agitate two adult humpback whales. Further observation revealed a Weddell seal swimming between the two humpbacks. However, it could not be proven the humpback whales were truly protecting the seal; oftentimes killer whales will try to antagonize the larger humpbacks to determine if any are sick or weak.

To the expedition’s surprise a week later they witnessed a different pair of humpback whales preventing a killer whale from attacking a seal. As a group of killer whales successfully dislodged the Weddell seal from its ice flow, the helpless seal immediately swam towards the pair of humpbacks (who were swimming nearby). The humpback closest to the seal, rolled on its back and pushed the seal onto its chest (using its flippers). Following the second display of such behavior the researchers concluded humpback whales were indeed exhibiting allomaternal care towards the seals.

*This blog post was derived from the article titled, “Save the Seal” published in Natural History’s November 2009 issue.

Update from the outer banks

It's been a good week down here at the beach.  Perfect weather for a few days giving way to wind and rain today.  We saw lots of interesting wildlife, from your standard shells and crab parts on the beach, a good diversity of shore birds, a pod of dolphins, one whale, a fox and lots of deer.

Here's a little practice with your knowledge of Atlantic Coast mollusks.  How many of the following taxa can you name:

And here are some shots of taxa that we will work with in lab this week - Arthropods and Echinoderms. The sea star on the left (the genus Asterias) was pretty fresh, but dead, and became a bit smelly over the last few days.  The other sea star is Astropecten.  The crabs are all specimens of Persephona punctata - a purse crab.  There were lots of these washed up on the beach.

Check back for another post tomorrow that will have some video on types of breakers.  This will be one of our topics for Monday's class.

Based on research on dolphins, it has been found that the way we treat them may affect them psychologically. Dolphin brains are very large and are second to humans based on the brain to body size relationship. Their brains are very well developed and have many of the same characteristics as our brains do. They are able to recognize themselves and are very intelligent animals.

When humans capture them and put them in captivity for entertainment purposes, they may be doing psychological damage to the dolphins. In knowing this, capturing dolphins has become an issue under ethical scrutiny. It has become an issue to figure out what effects we could be having on these delicate animals. Hopefully more research can be done in order to determine what effects we are having on dolphins. We need to protect all animals and we need to know whether we are doing harm or good.

Severe Red Tides Predicted for 2010

Many studies have been conducted to watch for red algal blooms. These red blooms are indirectly toxic to humans, because filter feeding mussels eat the algae. The toxins are passed to humans when ingested, which causes paralytic shellfish poisoning (PSP).

Scientists follow algae cysts that settle during colder times of the year, in order to monitor the severity of algae blooms. When toxicity levels become to high local fisheries are shut down to protect human health. Alexandrium fundyense is a toxic algae being monitored by the NOAA scientists in the Gulf of Maine. Over the past few years Alexandrium fundyense dormant cysts have been increasing in abundance and producing large blooms. These algae are transported, by winds and currents, a large distance on the New England coast Near the end of 2009 water samples surveyed an abundance of cysts in the water, leading to the prediction of a severe and toxic algae bloom.


Severe Red Tides Predicted for 2010

Powerpoint presentation

Hey all,

I realize this is a little late for our lab practical but I have put together a PowerPoint presentation that has pictures of all the shells that we identified in lab. If you would like me to send you the presentation, I would be more than happy to attach it to an email. Just shoot me an email at khuff1@ashland.edu and I'll send you a copy. I'll check my email before I go to bed but if you still want the PowerPoint regardless, I can still send it to you. Just thought I would offer.

Barnacles Flourish in Zones with Upwelling

Most marine ecologists believe that larvae of barnacles and mussels hitch a ride on offshore currents in the presence of upwelling, therefore most of the larvae are absent from coastal intertidal zones. Jon Witman and his team members have recently concluded that barnacles are actually present in zones with vertical upwelling and attach onto rock walls even more when the current is stronger. In vertical current zones the larvae are being bounced up against the rocky walls and find a spot to latch onto according to Witman. He refers to this process as "a contact game" where the larvae are using the rocks to settle. This study can change how scientist view the effect upwelling has on marine communities. Witman and his team believe that this study can prove true to other rocky intertidal organisms and ecosystems as well, if more underwater experiments are conducted.

The full article gives more insight into the study Witman and his team conducted.

• Article:
• Image: Barnacles, credit to Jon Witman and Brown University