Tuesday, April 19, 2011

Tilapia in Sewage Ponds


J. Samuel Suffern, S. M. Adams, B. G. Blaylock
C. C. Coutant and C. A. Guthrie
Environmental Sciences Division
Oak Ridge National Laboratory
Oak Ridge, Tennessee 37830


Studies vere conducted to evaluate the potential of monosex hybrid
tilapia ( ? T_. mossaabica x ^ T. hoi-norum) in waste-heat polyculture
systems. The optimum growth temperature for this! hybrid vas found to be
32 C in laboratory experiments. Experiments in sewage pond cage culture
in the temperature range 01" 23-33°C at stocking densities of ^ 53 fish/m
were also conducted. At fish sizes between 5 and: 12 cm TL, estimated
annual pr-durtion is approximately 50,003 kg/ha/yr (50,000 Ib/acre/yr).
Pish in the sewage oxidation ponds grsv significantly faster than
fish fed trout chow at optinun ter.pcrs.ture in the laboratory, even
though temperatures in the sewage ponds averaged below the optimum
growth temperature. Techniques to accelerate growth rates are being
explored. Exposure to garsna radiation (530 rads), known to cause significant
increases in channel catfish growth rate;, was found to have a
similar effect on tilapia. After a 20-week growth period, exposed fish
weighed an average of 20^ more than controls.

Spring Lake - HAB - Alum

Spring Lake waterfront community optimistic for alum’s prolonged progress

Village of Spring Lake

Village of Spring Lake

Spring Lake, Mich. residents are pleased with the continued results of an aluminum sulfate, or alum, treatment on Spring Lake. For years, the lake was plagued with algal blooms, rendering the water unusable for recreation. Whilealgal blooms manifest naturally and possibly seasonally contingent on weather and water condition, their growth can be provoked by human activity such as industrial and agricultural waste drainage as well as natural factors like temperature and water traits.

High numbers of algal bloom result in lower levels of dissolved oxygen and death of aquatic plant and animal life. Spring Lake is extremely eutrophic and has high percentages of nutrient cycling, which caused prevalent algal blooms to appear in summer months. However, a Grand Valley State University studyconducted in 2010 has confirmed water quality in the lake has improved tremendously.

Six years ago, the Spring Lake Board devised a multipart plan to improve and watch over the lake’s water quality for a decade. The project included treating the lake with aluminum sulfate. Before treatment, Spring Lake’s phosphorous levels were approximately 325 parts per billion. In 2005, nearly 1.2 million gallons of alum were sprayed over deep sections of the lake.

Alan Steinman, director of GVSU’s Water Resources Institute, said the 2010 study measured the 2005 phosphorus levels against 2010 levels, and he found they had plummeted to less than 30 parts per billion. Although phosphorus levels have increased somewhat, Steinman is optimistic.

“…It is still significantly lower than 2003. I was very pleased by the continued effectiveness of the alum,” he said.

Steinman is not the only one pleased with the results. Bruce Kennedy, a Spring Lake resident, remembers the condition of the lake prior to treatment.

“The algae blooms we experienced in the past were like pea soup,” he said, adding that he thought the alum treatment has worked well.

Although the treatment has been largely successful, Steinman warned against treating the alum as a cure-all. The alum deals with the effects of the problem rather than the problem itself, he said. It attaches itself to the phosphorus, removing it from the water and pulling it into the sediments at the bottom of the lake.

“The alum treatment has been effective five years later,” he said. “But it is impossible to say how much longer it is going to last.”

Spring Lake waterfront residents hope for continued success from chemical treatment [Muskegon Chronicle]
Spring Lake Phosphorus Project-Project Information [Annis Water Resources Institute]
Algal blooms in fresh water [Water Encyclopedia]
The Reduction of Internal Phosphorus Loading Using alum in Spring Lake, Michigan [Wetland Biogeochemistry Laboratory, University of Florida]

Image Credit: http://www.springlakevillage.org/


Alum only deals with the symptom and not the problem.

The quantity used is very large - 1.2 Million gallons.

Alluminium may accumulate and become toxic

(if Copper sulfate were to be used as an Algaecide, copper would accumulate)

Tuesday, April 5, 2011

Redondo Beach, California Fish Kill

Nothing fishy about sardine kill

April 5, 2011 By Pamela J. Johnson

Doctoral candidate Beth Stauffer (left), research technician Alyssa Gellene, and Astrid Schnetzer, assistant research professor, all of David Caron's laboratory use an EcoMapper to measure the oxygen level and other water data toward the end of the cleanup effort at King Harbor. Credit: Carl Oberg

Algal bloom specialist David Caron knows exactly what caused the death of 2.5 million sardines at King Harbor and is producing a paper on his research. The city of Redondo Beach gave him

The few million silvery that recently went belly up at Redondo Beach have been removed and the rotten egg smell has nearly dissipated.

But the fish kill story at King Harbor is not over.

“We’re going to have one of the best documented events of this kind that has ever been done probably anywhere in the world,” said David Caron, professor of biological sciences in USC Dana and David Dornsife College of Letters, Arts and Sciences.

“Our sensor equipment was in the water before, during and after it happened; luckily we had one right at ground zero,” Caron said. “And we physically got there the day it happened.”

Caron and his team are compiling their research on the March phenomenon in which more than 2 million — 175 tons — of sardines swam into the marina and died. An expert in aquatic ecosystems, Caron and his researchers are working closely with the city of Redondo Beach and King Harbor in finding answers about what caused the phenomenon and how such a fish kill may be prevented. They are also monitoring what is being done with the fish corpses.

Instruments suspended in the harbor throughout the event revealed that the fish were killed by a lack of oxygen in the harbor water — not toxins from an algal bloom which some news outlets had erroneously reported. Caron’s team also used an EcoMapper to help characterize water quality. The EcoMapper is a self-propelled device that traverses the water with a scanning sonar, mapping the ocean floor and collecting real-time water quality data.

“The fish were jammed in a small space in the harbor and ran out of oxygen,” Caron said. Although not the cause of death, the stomachs in the dead fish contained algae that produced domoic acid, a heterocyclic amino acid associated with harmful algal blooms. They ate the toxins before crowding into the harbor and running out of oxygen, Caron said, adding that a significant toxic algal bloom did exist in the coastal waters off the Palos Verdes Peninsula at the time of the event.

Caron and his researchers have been studying King Harbor since a fish kill occurred there in 2005. In 2006, they began taking weekly water samples and the next year, installed sensors that measure in part the temperature, salinity, chlorophyll and plant pigment in the water. Their sensors record the measurements every half hour, detecting any and toxic algae that may be present.

“This allows us to have a finger on the pulse on what’s going on out there,” Caron said. “This most recent event happened virtually overnight.”

Early March 8, Caron received a call from one of the marinas about the dead fish, which had started perishing overnight. Several of Caron’s researchers were dispatched right away. Astrid Schnetzer, research assistant professor, was one who arrived the first day, then returned to collect samples and measurements for several consecutive days with engineering technician Carl Oberg, lab technician Alyssa Gellene and Ph.D. candidates Beth Stauffer and Erica Seubert.

“It became so packed with sardines you couldn’t see the water,” Schnetzer recounted, adding that in some places a 3-foot-thick layer of fish had settled along the harbor floor. “Fish corpses were everywhere. It looked as if you could walk between the boats across the sardines.”

After a few days, it got worse.

“The smell made me nauseous,” she said. “People were complaining that it made their eyes burn. It was the most rotten straightforward smell you can imagine.”
All their effort was worth it.

“We’ve been there waiting for something like this to happen for five years,” Caron said. “When these events usually happen, we’re basically chasing the ambulance. By the time we get there it’s over. In this case, we were there before it happened.”

Caron and his team have also been honored by the city of Redondo Beach, which acknowledged their assistance and expertise involving handing the fish and the inquiries surrounding the event. Caron has given many interviews on the science behind what occurred, has worked with the city on cleanup and is still monitoring the aftermath.

Right now, Caron is ensuring that all toxins in the fish are removed before they are turned into compost.

“The composting process should take care of any toxins,” he said, holding up a coin medallion engraved with King Harbor that Redondo Beach City Council members gave him during a recent public meeting to symbolize their appreciation. “No one has ever looked at the toxins [from a fish-die] during the composting process before.

“We know that in toxic blooms, the toxins don’t stay around forever, they get degraded by bacteria, light and increased temperatures. In the sea, there is a chemical and biological degradation of toxins, that we know. We don’t know if that applies to composting, but we’re about to find out.”

He’s not a fish behaviorist, so cannot say definitively what drove so many fish into the harbor at once. It could have been that predators chased the schools into the harbor, he said. Or possibly the domoic acid they ate caused the fish to become disoriented and swim erratically.

“You can speculate all sorts of things, but in fact nobody really knows what toxins will do to behavior in fish,” Caron said. “In the past, people have suggested it might cause swimming abnormalities but most recent evidence suggests that it probably doesn’t.”

Larger mammals such as sea lions who feed on toxic blooms do develop distinct neurological symptoms — resulting from nausea to convulsions and seizures to death, he said.

“There were thousands of birds feeding on the dead fish,” Caron said. “And we haven’t seen an abnormal increase in the mortality of birds or marine mammals, so that’s a good sign.”

Caron and his team’s research will also help Redondo Beach come up with solutions that may help the city avoid a similar situation in the future such as possibly putting an oxygenation system in place at the harbor. The Redondo Beach Patch reported that cleanup would cost the city at least $300,000.

“They may use it only once every three years or so,” Caron said of the aeration scheme, one of many possible solutions. "But they are going to avoid a costly problem.”

Provided by University of Southern California (news : web)

Saturday, April 2, 2011

Lake Winnipeg, Canada

Winnipeg Free Press - PRINT EDITION

Losing the lake

David Suzuki narrates CBC documentary on the failing health of Manitoba's freshwater jewel and its global implications

David Suzuki narrates CBC documentary on the failing health of Manitoba's  freshwater jewel and its  global implications

Enlarge Image

David Suzuki narrates CBC documentary on the failing health of Manitoba's freshwater jewel and its global implications

As TV-documentary titles go, it doesn't get much more direct, urgent and plaintive than this: Save My Lake.

That's the strongly worded sentiment contained in Sunday's special-edition broadcast of CBC's The Nature of Things with David Suzuki (7 p.m. on CBC), and the body of water so desperately in need of salvation is pretty close to home: Lake Winnipeg.

"Lake Winnipeg is a huge example of what is happening to lakes all over the world," says Kemp, co-director and executive producer of the film for Toronto-based Stornoway Productions. "This is happening to any place where you've got sewage effluent or fertilizer or agricultural runoff working its way through the water system. It's a universal issue, and it has to be dealt with.It is, says filmmaker Paul Kemp, a very local story with huge global implications.

"People have begun to wake up to the idea that the oceans are threatened, but maybe it's time to start thinking about the fresh water and the watersheds of our country, too."

Kemp, who was born in Winnipeg but currently resides in Toronto, said the inspiration for doing a documentary examination of Lake Winnipeg's plight came from a startling event that arose while engaged in the most mundane of cottage-country activities.

"A couple of years ago, I was walking with my son along one of the beaches at Victoria Beach, and he went into the water and came out covered, up to his neck, in green goop," he said. "It was just caked on. I thought, 'We're not going in there any more,' and made myself a promise that I was going to look into it.

"We've always had a cottage; I've been going to that neck of the woods -- either Victoria Beach or Albert Beach -- for coming up on 40 years of my life, and I'm 41 now. I remember, when I was growing up, canoeing in that water, even drinking the water, and never thinking too much about the water quality."

After doing a bit of research and consulting with a couple of scientists to try to understand the reasons for his green-slime scare, Kemp felt there was enough to the story to justify pitching it to the public broadcaster. He admits he was a bit surprised by the swift and certain level of support the story received.

Save My Lake couldn't come at a better time for folks who live and work on Lake Winnipeg, including Dr. Al Kristofferson, the Gimli-raised scientist who heads the Lake Winnipeg Research Consortium.

"Using satellite imagery, we've been able to go back a couple of decades, and in the last decade, we've seen consistent larger (algae) blooms, in some cases covering the entire north basin of the lake," said Kristofferson. "It has become very evident to all of us, and it's been over the last 15 or 20 years that it has become very noticeable."

In shooting Save My Lake last summer, Kemp and his film crew accompanied Kristofferson on one of their research trips around the lake, during which they collected water samples and core specimens from the lake's bottom. The evidence they found suggests that Lake Winnipeg's downward spiral may have begun much earlier than most observers believe.

"One way you can actually go back in time is to take a core sample of the sediment of the lake," he explained. "You take a cylinder and drive it down into the sediment, and the farther down you go, the farther back in time you go. There's a core that was taken in the north basin in 1994, and that core, if you examine it carefully, indicates that this problem isn't something that just happened in the last 20 years. This is something that has been building for the last 50 years."

To say the least, working on this film was an eye-opening experience for Kemp. He said the most interesting -- and, from an environmental perspective, alarming -- aspect of his Lake Winnipeg education has been learning the massive scope of the land mass that empties into the lake.

"I didn't realize how big the watershed of Lake Winnipeg is," he said. "I didn't realize that if you flush your toilet in Calgary or Banff, it's eventually going to work its way to Lake Winnipeg. Lake Winnipeg is the end of the pipe for some massive rivers -- even the Bow River and the South Saskatchewan River make their way to the lake.

"I knew about the Red and the Assiniboine and the Winnipeg River, because I grew up there, but I guess I didn't realize that whatever flows off of every farm in Western Canada ends up working its way to the lake.... (The watershed) actually goes through four provinces and four states."

As alarming as the information in Save My Lake seems, both Kemp and Kristofferson agree that there is reason for optimism. The issue has been identified; action is being taken; and, as the success of efforts to rehabilitate Lake Erie a couple of decades ago has shown, Lake Winnipeg's current algae-bloom crisis needs to be viewed as a solvable problem.

"I hope we start to recognize that we're all part of the problem, and we can all be part of the solution," said Kemp. "It sounds like a cliché, but the fact is that everything we do -- from the soap we use to the fertilizer that goes on our farmland to where our sewage goes -- has to be looked at.... It's a very difficult issue, because there are so many 'point sources' of pollution contributing to the problem."