Tag Archives: Algae


The Algae Which are Bent on World Domination?

An Israeli Ph.D student’s case study on a kind of deadly algae, may just help to make drinking water safer for people and animals alike.

It almost sounds like a zany plot from a cartoon from a super villain: A beautiful, yet very deadly, kind of blue-green algae, forces other microorganisms found in fresh water to do its bidding, which enables them to over run the water, and threaten the health of people and animals all over the world.

These devious cyanobacteria algae – known as the thorns in the sides of the freshwater populaces – are not cartoon characters however. A paper recently published on August the 12th in the journal Current Biology, a scientist over at the Hebrew University of Jerusalem explains to us how they take over their competition and are very prolific, raising concern around the world due to the detrimental impact they could pose on the quality of water.

By enlightening us on how the algae function, Yehonatan Bar-Yosef’s case study can help other experts find out how to deal with this threat and ensure that drinking water is safe for humans and animals all over the world.

Back in 1994, a huge bloom of this toxic algae was discovered in Lake Kinneret, which is also known as the Sea of Galilee. A lot of the potable water for Israel is taken from the Kinneret, so this discovery really raised red flags.

Luckily for us Bar-Yosef is delving into the matter, and could conceivably come up with an enzyme to help battle this dastardly algae.

Good luck Bar-Yosef, we are all rooting for you. Hopefully he will crack the code, and help everyone in the world.

Coral Facing Imminent Threat From Toxic Algae

Reefs

Healthy reef

Blooms of toxic algae could possibly wipe out coral reefs.

Researchers who have been studying the coral reefs in the Gulf of Oman have sounded the alarm after a big algae bloom laid waste to an entire coral reef in just three short weeks.

Some ninety-five percent of the hard coral directal under the algae died off, and seventy percent fewer fish were found in the vicinity.

The algae grows rapidly and hog all the sunlight and oxygen which the coral need to survive.

Add in climate change, development along the coasts, overfishing and pollution and you have a rather bleak outlook for the coral reefs of the world.

The biggest threat facing the coral reefs is climate change, which has caused many coral bleaching events around the globe.

However, this latest discovery, which was published in the journal Marine Pollution Bulletin postulates that algal blooms are just as much a threat to the coral reefs.

Scientists from the United Nations University Institute for Water, Environment and Health had taken it upon themselves to study the environment of two different coral reefs in the Gulf of Oman.

After they finished up their first study, an algae bloom which measured over 500 square kilometers happened in the area.

After the scientists made a return visit some three weeks after the fact, they discovered that the coral under the bloom had been almost completely destroyed.

So, it appears that the coral is facing yet another threat, algae. Scientists are now working on a way to help the reefs, but since this is a new phenomena it might take some time.

Damsel Fish Control Algae: Cultivate What they Like

There is a certain kind of damsel fish, the Stegastes Nigrigans, which will actually selectively cultivate the algae they prefer to feed on. They have shown to actually encourage the growth of Polysiphonia, their preferred food, and limit the growth of other algae which they can’t digest as well. Researchers, which are writing in the open access journal BMC Evolutionary Biology, have been investigating the algae preferences of damselfish and explore their intricate cultivating practices all across the Indo-West Pacific region.

Hiroki Hata from Ehime University, Japan, worked with a team of researchers to explore this ‘gardening’ behavior. He said, “We surveyed 320 territories of 18 damselfish species and thoroughly examined algae from each fish territory from coral reefs in Egypt, Kenya, Mauritius, the Maldives, Thailand, Borneo, the Okinawa Islands, and the Great Barrier Reef. We found that although the crop alga species shifted in the West Indian Ocean, the intensive farming by damselfish was seen throughout this geographic range”.

It has been found that damselfish do not posses any organs which would allow them to process cellulose fibers, and they aren’t able to digest many species of algae. The most common type of algae they feed on is the red algae known as Polysiphonia. Unfortunately, this kind of algae is not very competitive and the damselfish lend a helping hand by killing off competing algae.

Lake Erie In Dire Condition

Buffalo, New York – The NOLENS (Near shore and Offshore Lake Erie Nutrient Study) is going to be wrapping up the month, after a long year of rigorous research which was headed by Chris Pennuto. Chris Pennuto, a research scientist at the Buffalo State College Great Lakes Center, is a biology professor who has taken an interest in the state of Lake Erie.

The central part of the research was focused on the question “Why didn’t Lake Erie’s health improve as expected when the amount of phosphorus discharged into the lake decreased?”

Other members who were a part of the project were Lyubov Burlakova, a research sicentist associated with the Buffalo State College Great Lakes Center; Alexander Karatayev, who directs the center; and Alicia Perez-Fuentetaja, a research scientist and associate professor of biology.

Back in the 60’s, Lake Erie was all but considered defunct. Ironically, one of the most prominent factors which caused Lake Erie to be in this defunct status was it’s level of nutrients. Karatayev explained, “Nutrients are like calories. You need calories to live, but if you eat too many of them, you can get very, very sick.” One of the nutrients on that list is phosphorous.

For this reason, and a variety of other contributing factors, Lake Erie has huge algal mats still growing on the lake bottom. Pennuto and his team are slowly getting to the bottom of it, and hope to have a plan of action to present soon, to remedy the situation.

Thousands of seabirds killed by algae on the U.S. west coast

An algae bloom stretching from the Olympic Peninsula in Washington state to the northern parts of Oregon has killed thousands of seabirds by stripping them of the natural oils that keep them waterproof. Without these oils, seabirds quickly get wet and succumb to hypothermia.

This is huge,” says Professor Julia Parrish, a marine biologist who leads a seabird monitoring group at the University of Washington. “It’s the largest mortality event of its kind on the West Coast that we know of.”

Similar mass-deaths have taken place along the coast of California before, but this is the first time it is reported from the states of Oregon and Washington. Also, as far as we know, the California die-offs affected hundreds of seabirds, not thousands.

The so called algae “bloom” consists of tiny single-celled algae of the species Akashiwo sanguinea.

Marine biologists have not been able to determine the reason for the sudden appearance of up to a million Akashiwo sanguinea cells per litre seawater, but recent storms in the area may have contributed to the severity of the problem by breaking up the algae.

When the algae get whipped, it turns into what can best be described as a bubbly soap which sticks to the seabirds.

It looks like they’re [the seabirds] lying in a sea of bubble bath,” said Greg Schirato, regional wildlife program manager for the Washington Department of Fish and Wildlife.

Clemson researchers claim algae killed the dinosaurs

dinosaurAccording to geologist James W. Castle and ecotoxicologist John H. Rodgers, both of the Clemson University in South Carolina, toxin-producing algae caused or contributed to the mass extinction of dinosaurs.

After spending two years analyzing data from ancient algal deposits, so called stromatolite structures, the researchers have found evidence that blue-green algae where present in sufficient quantities to kill off countless numbers of plants and animals living in the ocean or on land at the time. Blue-green algae may not seem very harmful, but they produce toxins and deplete oxygen.

Other researchers have suggested that phenomena such as volcanic activity, climate change, sea level changes or asteroids are responsible for the five major extinctions and a number of other significant die-offs during the part of Earths history during which life with skeletons or shells have existed. According to Castle and Rodgers, all these phenomena contributed to the mass deaths but algae was the most important factor.

The fossil record indicates that mass extinctions… occurred in response to environmental changes at the end of the Cretaceous; however, these extinctions occurred more gradually than expected if caused solely by a catastrophic event,” Castle and Roger argue in their work.

The part of the study that has caused the most debate so far is the warning that current global warming may cause similar die-offs, since our current environmental conditions show significant similarity to times when mass die-offs have occurred.

This hypothesis gives us cause for concern and underscores the importance of careful and strategic monitoring as we move into an era of global climate change,” Castle and Roger writes, adding that the level of modern toxin-producing algae is presently increasing, and their geographic distribution is expanding

The paper has already gained a lot of attention within the scientific community.

Scientists from around the world have been sending us data that support our hypothesis and our concern about the future,” says Rodgers. “I look forward to the debate this work will generate. I hope it helps focus attention on climate change and the consequences we may face.”

You can download the entire “Hypothesis for the role of toxin-producing algae in Phanerozoic mass extinctions based on evidence from the geologic record and modern environments” from Clemson University.

http://www.clemson.edu/media-relations/files/articles/2009/2336_295_mass_extinctions.pdf

The work has also been published in the March 2009 issue of the journal Environmental Geosciences.

Ocean-going robot will warn us of harmful algal blooms

ESPThe Monterey Bay Aquarium Research Institute (MBARI) have developed an aquatic robot capable of collecting algal cells from the ocean and extracting the genetic information needed to identify them. The robot, which can accurately be described as a seafaring mobile analytical laboratory, can also extract toxins from the algae samples, thereby allowing scientists to assess the risk to humans and wildlife.

The MBARI-designed robot, formally known as the Environmental Sample Processor, or ‘ESP,’ for short, has now been successfully used by scientists from NOAA’s National Centers for Coastal Ocean Science to conduct the first remote detection of an algal species and its toxin below the ocean’s surface.

The global distribution, frequency, duration and severity of harmful algal blooms are believed to be on the increase and the new robot will make it much easier for scientists to assess the situation and relay accurate information to coastal managers and public health officials.

MbariOur public health monitoring program is one of the many groups that can benefit directly from the ESP technology and ability to provide an early warning of impending bloom activity and toxicity,” said Gregg Langlois, director of the state of California’s Marine Biotoxin Monitoring Program. “This is critical information for coastal managers and public health officials in mitigating impacts on the coastal ecosystem, since the toxicity of these algae can vary widely from little or no toxicity to highly toxic.”

The information obtained by ESP is transmitted to the laboratory via radio signals.

More details about the project can be found in the June issue of the journal Oceanography.

Pictures by mbari

Record breaking Gulf of Mexico ‘Dead Zone’ this summer

gulf of mexicoAccording to predictions made by a team of NOAA-supported scientists from the Louisiana Universities Marine Consortium, Louisiana State University, and the University of Michigan, the Gulf of Mexico “dead zone” is likely to become record big this summer. If there predictions are true, we will see a dead zone the size of New Jersey (7,450 to 8,456 square miles). Additional flooding of the Mississippi River since May can however increase these numbers even further.

What is the Gulf of Mexico ‘dead zone’?

The dead zone is an area off the coast of Louisiana and Texas in the Gulf of Mexico where the oxygen level seasonally drops so low that most life forms living in and close to the bottom dies.

Dead zones are the result of large amounts of nutrients reaching the water, e.g. through waterways polluted by sewage and agricultural runoff. The excess nutrients stimulate rapid and massive algae growth in the affected area, a so called algae bloom. When the algae die, they sink to the bottom where oxygen dependant bacteria begin to break them down. The decomposition process consumes vast amounts of oxygen and soon the bottom and near-bottom waters become so oxygen depleted that all sorts of oxygen breathing organisms begin to die. This so called hypoxic area (an area where the oxygen levels are low to non-existent) is not just a problem for wildlife; it can also damage the economy of nearby states since it destroys habitat necessary for commercial and recreational Gulf fisheries.

The largest dead zone on record appeared in 2002 and measured 8,484 square miles.

Mississippi and Atchafalaya Rivers too rich in nutrients

During April and May this year, the Mississippi and Atchafalaya Rivers experienced heavy water flows that were 11 percent above average.

The high water volume flows coupled with nearly triple the nitrogen concentrations in these rivers over the past 50 years from human activities has led to a dramatic increase in the size of the dead zone,” said Gene Turner, Ph.D., a lead forecast modeler from Louisiana State University.

As with weather forecasts, this forecast uses multiple models to predict the range of the expected size of the dead zone“, said Robert Magnien, Ph.D., director of NOAA’s Center for Sponsored Coastal Ocean Research. “The strong track record of these models reinforces our confidence in the link between excess nutrients from the Mississippi River and the dead zone.”

Communication between corals and algae may be impaired by climate change

The intricate symbiotic relationship between reef building corals and algae seem to rely on a delicate communication process between the algae and the coral, where the algae is constantly telling the coral that the algae belongs inside it, and that everything is fine. Without this communication, the algae would be treated as any other invader, e.g. a parasite, and be expelled by the coral’s immune system.

Researchers now fear that increased water temperature will impair this communication system, something which might prove to be the final blow for corals already threatened by pollution, acidification, overfishing, dynamite fishing, and sedimentation caused by deforestation.

According to a new report, a lack of communication is likely to be the underlying cause of coral bleaching and the collapse of coral reef ecosystems around the world.

Reef building corals can defend themselves and kill plankton for food, but despite this they can not survive without the tiny algae living inside them. Algae, which are a type of plants, can do what corals can’t – use sunlight to produce sugars and fix carbon through photosynthesis.

coral reef

Some of these algae that live within corals are amazingly productive, and in some cases give 95 percent of the sugars they produce to the coral to use for energy,” said Virginia Weis, a professor of zoology at Oregon State University. “In return the algae gain nitrogen, a limiting nutrient in the ocean, by feeding off the waste from the coral. It’s a finely developed symbiotic relationship.

If this relationship were to collapse, it would be death sentence for the reef building corals.

Even though the coral depends on the algae for much of its food, it may be largely unaware of its presence, said Weis. We now believe that this is what’s happening when the water warms or something else stresses the coral – the communication from the algae to the coral breaks down, the all-is-well message doesn’t get through, the algae essentially comes out of hiding and faces an immune response from the coral.”

This internal communication process, Weis said, is not unlike some of the biological processes found in humans and other animals.

Researchers now hope that some of the numerous species of reef building corals found globally and their algae will be more apt at handling change.

With some of the new findings about coral symbiosis and calcification, and how it works, coral biologists are now starting to think more outside the box,” Weis said. “Maybe there’s something we could do to help identify and protect coral species that can survive in different conditions. Perhaps we won’t have to just stand by as the coral reefs of the world die and disappear.”

The new research has been published in the most recent issue of the journal Science and was funded in part by the U.S. National Science Foundation.

Green plume from Venezuela have now reached the Virgin Islands and Puerto Rico

A strange algae plume has turned the normally crystal clear Caribbean Sea around the Virgin Islands green down to a depth of roughly 80 feet (25 metres) and sharply decreased visibility in these popular dive waters. How and if the plume will have any long-term effect on the region’s marine life remains unknown.

Tyler Smith, assistant professor at the Center for Marine and Environmental Studies at the University of the Virgin Islands, said that when he went diving Tuesday the visibility inside the plume was no more than 10 feet (3 metres). Below 80 feet, the water was just as clear as normally.

The reason behind the extraordinary plume can be found in South America, in the Orinoco River which flows through Venezuela before reaching the Atlantic Ocean. When the Orinoco outflow is larger than normal, the vast amounts of nutrient-rich freshwater from Venezuela cause a major algae bloom in the nearby ocean. Mixed fresh- and saltwater is lighter than seawater and will therefore rise to the top of the water column.

Orinoco virgin islands

It’s very stable, so it just sits there,” Smith explains.

Carried by currents, the algae plume has now spread from the South American east-coast to the Caribbean Sea and can currently be seen not only off the British and U.S. Virgin Islands but in Puerto Rican waters as well. The first patch was noticed by Smith and his colleagues in the waters off St. Croix on April 9.

When the amount of photosynthesising alga increases in a region, it attracts all sorts of organisms that feed on algae and make it possible for these populations to boom as well. The algae plume around the Virgin Islands supports an entire food chain of marine life, including plankton, jellyfish, crustaceans and fish. It is not dangerous to swim or scuba dive in, but some people might dislike the high density of jellyfish.

This is an event that occurs every year, but we haven’t seen it come this far north,” says Trika Gerard, marine ecologist with the U.S. National Oceanic and Atmospheric Administration (NOAA). In a stroke of good luck, a NOAA research vessel was scheduled to research reef fish in these waters from April 7 to April 20 – right at the peak of the unexpected plume.

To find out more about how the plume effects marine life, the Caribbean Fisheries Management Council is urging anyone who goes out fishing in the green plume to report their location, target species and success rate of each trip. According to local fishermen the fishing is always awfully bad when the water is green, but this has not been scientifically researched yet and all data is of interest.

You can reach the Caribbean Fisheries Management Council by calling (787) 766-5927. Their website is http://www.caribbeanfmc.com.