Monday, August 29, 2011
Jellyfish Invasion
Monday, August 22, 2011
Great Barrier Reef - Algal Blooms

The Sea in many places is here cover’d with a kind of a brown scum, such as Sailors generally call spawn; upon our first seeing it, it alarm’d us, thinking we were among Shoals, but we found the same depth of Water were it was as in other places.
Sailing through the Coral Sea outside the Great Barrier Reef, Captain James Cook made those observations on August 28, 1770. His journals contain the first mention of the long brown filaments of cyanobacteria that arecommon along the Australian coast.
On August 9, 2011, the Moderate Resolution Imaging Spectroradiometer (MODIS) on the Aqua satellite captured this view of a similar band of brown between the Great Barrier Reef and the Queensland shore. Though it’s impossible to identify the species from satellite imagery, such red-brown streamers are usually trichodesmium.Sailors have long called these brown streamers “sea sawdust.”
Trichodesmium, a form of cyanobacteria, are small, usually single-celled organisms that grow in the ocean and produce food through photosynthesis like plants. They play an important role in Earth’s oceans because they convert nitrogen gas from the atmosphere to ammonia, a fertilizer that plants can use to grow. At the same time, trichodesmium removes carbon dioxide from the atmosphere. Their blooms often occur in warm, nutrient-poor waters. Charles Darwin observed one such bloom from the HMS Beagle in 1832, marveling that “their numbers must be infinite.”
References
- Cook, J. (1771). Captian Cook’s journal during his first voyage round the world made in H.M. Bark 1768-71.University of Adelaide, 2010. Accessed August 16, 2011.
- Darwin, C. (1845). Voyage of the Beagle. Published on Literature.org. Accessed August 16, 2011.
- Kuring, N. Great Barrier Reef. NASA Ocean Color Web. Accessed August 16, 2011.
- University of California Museum of Paleontology. (n.d.). Introduction to the cyanobateria. Accessed August 16, 2011.
- Woods Hole Oceanographic Institution. (2002, September). Trichodesmium. Accessed August 16, 2011.
NASA Earth Observatory image created by Jesse Allen, using data obtained from the Land Atmosphere Near-real time Capability for EOS (LANCE). Caption by Holli Riebeek.
- Instrument:
- Aqua - MODIS
Barents Sea - Algal Bloom

Brilliant shades of blue and green explode across the Barents Sea in this natural-color image taken on August 14, 2011, by the Moderate Resolution Imaging Spectroradiometer (MODIS) on the Aqua satellite. The color was created by a massive bloom of phytoplankton that are common in the area each August. The clear view is a rare treat since the Barents Sea is cloud-covered roughly 80 percent of the time in summer.
Plankton blooms spanning hundreds or even thousands of kilometers occur across the North Atlantic and Arctic Oceans every year. Many species thrive in the cooler ocean waters, which tend to be richer in nutrients and plant life than tropical waters.
In this image, the milky blue color strongly suggests that the bloom contains coccolithophores, microscopic plankton that are plated with white calcium carbonate. When viewed through ocean water, a coccolithophore bloom tends to be bright blue. The species is most likely Emiliana huxleyi, whose blooms tend to be triggered by high light levels during the 24-hour sunlight of Arctic summer. The variations in bloom brightness and color in satellite images is partly related to its depth: E. huxleyi, can grow abundantly as much as 50 meters below the surface.
Other colors in the scene may come from sediment or other species of phytoplankton, particularly diatoms. The Barents Sea usually witnesses two major bloom seasons each year, with diatoms peaking in May and June, then giving way to coccolithophores as certain nutrients run out and waters grow warmer and more layered (stratified).
The area in this image is located immediately north of the Scandinavian peninsula. The region is a junction where several ocean current systems—including the Norwegian Atlantic, the Persey, and east Spitsbergen currents—merge and form a front known as the North Cape Current. The intersecting waters, plus stiff winds, promote mixing of waters and of nutrients from the deep.
Ice-covered for most of the year, the shallow Barents Sea reaches its warmest surface temperatures (6.6 C) in August, when ice cover is at a minimum and the water is freshest (less saline due to ice melt and river runoff) and most nutrient depleted. Those conditions, researchers have found, are perfect for coccolithophores to take over from other species and dominate the surface waters.
In a 2009 paper by Signorini et al, the researchers note:
Coccolithophores, among which E. huxleyi is the most abundant and widespread species, are considered to be the most productive calcifying organism on earth. They are important components of the carbon cycle via their contribution and response to changes in atmospheric CO2 levels...Coccolithophores appear to be advancing into some sub-Arctic Seas and climate change induced warming and freshwater runoff may be causing an increased frequency of coccolithophore blooms within the Barents Sea.
NASA recently sponsored a research cruise—known as ICESCAPE—in Arctic waters north of Alaska and Canada. Researchers were sampling coccolithophores there, among other species and environmental characteristics, to get a better view of the Arctic Ocean ecosystems and how they may be changing. The cruise is over, but you can still read the daily postings from six weeks at sea. Click here.
Related Reading
- Signorini, S. R., and C. R. McClain (2009), Environmental factors controlling the Barents Sea spring-summer phytoplankton blooms. Geophysical Research Letters, 36, L10604, doi:10.1029/2009GL037695.
- NASA Earth Observatory (1999) What is a Coccolithophore?" Accessed August 17, 2011.
- NASA (2011) ICESCAPE Blog. Accessed August 17, 2011.
NASA image courtesy Jeff Schmaltz, MODIS Rapid Response Team at NASA GSFC. Caption by Mike Carlowicz and Holli Riebeek, with interpretation from Barney Balch (Bigelow Laboratory) and Norman Kuring and Sergio Signorini of NASA's Goddard Space Flight Center.
- Instrument:
- Aqua - MODIS
Saturday, August 20, 2011
Algal Bloom in NY/NJ Bight: Help Needed!
Friday, August 19, 2011
Algal Bloom in NY/NJ Bight: Help Needed!
A huge algal bloom, indicated by the green color in the ocean water, was observed on August 17, 2011 in this True Color Satellite Image. The Mid-Atlantic Regional Association Coastal Ocean Observing System, MARACOOS, has posted this image and additional information and data on its website, click here. The bloom covered much of the New York/New Jersey Bight which extends from Montauk, NY (the tip of Long Island) to Cape May, NJ. Tuesday, August 2, 2011
Omega-3 taken in pregnancy could protect infants' health: study
Omega-3 taken in pregnancy could protect infants' health: study
UNITED STATES
Wednesday, August 03, 2011, 04:20 (GMT + 9)
A new study by Emory University suggests that babies will be protected against illness during early infancy if their mothers consume omega-3 fatty acids from supplements or fish during pregnancy.
The findings of the randomized, placebo-controlled trial were published online in the journal Pediatrics.
Scientists followed about 1,100 pregnant women and 900 infants in Mexico. The women were given daily supplements of 400 mg of Docosahexaenoic Acid (DHA) in the algal form or placebo from 18 to 22 weeks gestation through childbirth.
The researchers said no fear should exist of mercury contamination in DHA from algae, HealthDay reports.
Children whose mothers took DHA supplements were found to suffer from fewer colds and shorter illnesses at one, three and six months of age.
"This is a large scale, robust study that underscores the importance of good nutrition during pregnancy," said Usha Ramakrishnan, PhD, associate professor, Hubert Department of Global Health at Emory’s Rollins School of Public Health.
Ramakrishnan noted that, according to the study, pregnant women who take 400 mg of DHA are more likely to deliver healthier babies.
“There is research to suggest that the fatty acid composition of many of our cells—particularly the immune cells—affect their function,” Ramakrishnan commented,Health.com reports.
At one month of age, the infants in the DHA group had a reduced incidence of cold symptoms by 25 per cent, such a shorter duration of cough, phlegm and wheezing.
At three months of age, those infants spent 14 per cent less time sick.
At six months of age, those infants experienced shorter duration of fever, nasal secretion, difficulty breathing and rash, even though they had a longer duration of vomiting.
Ramakrishnan and her colleagues previously reported findings that babies of women pregnant with their first child who consumed 400 mg DHA during pregnancy delivered babies 100 g heavier at birth and 3/4 cm longer at 18 months of age.
The researchers also detected increased DHA levels in breast milk, and all of the infants in the study were breastfed.
“Recommending women to take a dose of up to 400 milligrams of DHA during pregnancy would be safe, [but] how much of a benefit there is we don’t know yet,” Ramakrishnan concluded.
The study was funded by the NIH and the March of Dimes Foundation.
Saturday, July 30, 2011
Agricultural pollution blamed for Lake Erie blooms, fish woes
Agricultural pollution blamed for Lake Erie blooms, fish woes
Published: Friday, July 29, 2011, 3:05 PM Updated: Friday, July 29, 2011, 3:13 PM
D'Arcy Egan, the Plain DealerRecent rains have pushed a load of nutrients from the major rivers to Lake Erie, provoking algal blooms around the lake like this one in 2010 and causing low oxygen zones.HURON, OHIO
The blooms are back on Lake Erie, and are just as destructive as in the 1960s when the most productive fishing lake in the world was declared dead. An overload of nutrients was the culprit a half-century ago. It is again, but from a different source.
Farmers from around the region are now being blamed.
"In the 1960s, we had an overload of nutrients from sewage treatment plants, industrial plants and phosphate-rich laundry detergent," said Jeff Tyson, the head of Lake Erie fishery management at the Lake Erie Research Unit in Sandusky. The walleye and whitefish populations plummeted and the popular blue pike became extinct.
"We managed to make changes starting in 1972 with the passage of the Great Lakes Water Quality Act, controlling the point source of phosphate pollution and banning phosphates in laundry detergent."
It worked.
Phosphate pollution declined, algal blooms subsided and walleye, yellow perch and smallmouth bass thrived. Lake Erie became the Walleye Capital of the World in the 1980s.
In recent years, farmers have been planting more corn to take advantage of high prices driven by the production of ethanol. They are loading fields with phosphate-rich fertilizer to enhance yields. As a result, silt, sediment and fertilizer are finding their way into the Lake Erie watershed. The problem is compounded by the U.S. Corps of Engineers dumping massive amounts of nutrient-rich sediment dredged from the Maumee River into Lake Erie
After a relatively dry summer, the rains over the last couple of weeks have resulted in major runoff from farm fields, triggering an algae-green cast to Western Lake Erie. Viewing satellite images of Lake Erie, the green waters are most evident near the mouth of the Maumee River, a major Lake Erie tributary.
"We fished just west of West Sister Island last week, and found low oxygen levels in that area," said Justin Chaffin, a PhD student at the University of Toledo's Lake Erie Center. "All of the walleye we caught were close to the surface, above the low oxygen layers caused by the bloom."
Tyson said the waters east of Kelleys Island are suffering from low oxygen, as well.
"Because of the low oxygen levels the fish move out, or they move up," said Tyson. "Walleye and even yellow perch will suspend over the low oxygen areas, sometimes diving down to the bottom to feed."
Anglers are finding large numbers of walleye in surprisingly shallow water from Huron to Vermilion where oxygen levels are normal, but not in deeper waters a few miles offshore, where catches had been very good a month ago. In some areas, anglers are finding yellow perch suspending well off the bottom, despite most of their preferred forage is found close to the lake bottom.
Eutrophication, when a body of water is inundated with an overload of nutrients that stimulate excessive plant and algae growth, is the biggest problem Lake Erie fisheries manager now face, said Tyson.
"Percids, the yellow perch and walleye, do not do well in a eutrophic lake," said Tyson. "We saw that in the 1960s, when their numbers crashed. It's happening again."
Unfortunately for Lake Erie anglers who favor perch, walleye and smallmouth bass, the species of fish that do well in eutrophic waters are sheepshead, channel catfish, white bass and white perch. The proliferation of white perch, a native of brackish water along the eastern U.S. coast that arrived in Lake Erie through the Welland Canal many years ago, is also impacting schools of yellow perch, said Tyson.
"There's no quick fix," said Tyson. "We have to make changes all around the watershed and limit the nutrients flowing into Lake Erie. We have to get the U.S. Department of Agriculture, the Ohio Department of Agriculture and the Ohio EPA on board. We must provoke a major change in farming practices."
Friday, July 29, 2011
Despite bit of a stench, Franklin's water is harmless
Despite bit of a stench, Franklin's water is harmless
Kevin Walters | The Tennessean
Until cooler temperatures or more rainfall come this way, the distinct odor of the drinking water coming from some taps in Williamson County and elsewhere will probably linger.
Officials with the county’s primary water supplier, the Harpeth Valley Utilities District, say the mix of lower water levels in the Cumberland River, scarce rainfall and extended hot temperatures of 95-100 degrees have spurred algae blooms in the water.
Those algae blooms create compounds — known as geosmin and 2-methyl isoborneol or MIB — that have left many wrinkling their noses and smarting from the water’s taste, despite increased water treatment.
Ultimately, water management officials say the treated tap water is safe to drink. But if you feel like the smell is more prevalent and the problem more widespread than in summers past, you aren’t alone.
“This year appears to be worse than usual, as of right now,” said John Barnes, assistant general manager of the utility district.
Reports of foul-smelling water come from as far away as Nashville, Hendersonville and cities in Rutherford County.
“It’s really everybody who has surface water,” said Franklin City Administrator Eric Stuckey. “It’s really everybody.”
Much of Williamson County’s water comes from the Cumberland River. Water is pumped here by Harpeth Valley for use by cities and other utility districts. In addition to buying water from HVUD, the city of Franklin pumps some of its drinking water from the Harpeth River and treats it at its Franklin water plant.
In Franklin, water department staffers have been furiously flushing water lines to get rid of the foul-smelling water. More than 200 hydrants have been flushed since the problem surfaced last week, city officials said, and staffers worked more than 122 hours of overtime.
At first, the problem seemed heaviest in southern parts of the cities, but reports of foul-smelling water have spread.
City spokeswoman Milissa Reierson said crews are focusing on hydrants located on dead-end lines, as those seem to be having the most difficulties.
Stuckey said he feels like the problem has lessened somewhat in recent days.
“I don’t know when it will completely resolve,” Stuckey said. “Rain helps. Lower temperature helps.”
To help improve the water’s taste at home, Barnes recommends chilling the drinking water, which might decrease the smell, or using a carbon filter for drinking water, which should improve the odor and taste.
“There shouldn’t be any concern about the safety of the water,” Barnes said.
Contact Kevin Walters at 615-771-5472 orkewalters@tennessean.com
