There are very few articles on the Internet about the role of Diatoms in the food chain and need for silica by Diatoms.
The Soundkeeper of Long Island Sound has written one such article on the research done by Dr Ellen Thomas of Yale University.
The Soundkeeper Mr Backer is also a State Representative of Connecticut.
http://www.soundkeeper.org/update_detail.asp?ContentID=299
Attack of the Jellifish--Is nitrogen pollution changing the food chain in the Long Island Sound?
By: Terry Backer and Julia Hyman
Ellen Thomas, PhD, a professor at Yale and Wesleyan University, released findings showing that nitrogen pollution, and perhaps warming waters, may have changed the basis of the food chain in the Long Island Sound. Her research shows that a key shift in populations of microscopic algae has been occurring over the last several decades. This fundamental shift in the Sound’s menu of who eats what is likely to cause many familiar species’ populations to decrease.
At the base of the Sound’s food chain are diatoms--single celled organisms that are found in fresh and salt water. Foraminifera, or forams, are also single celled organisms which adopt dazzling and intricate shapes with many looking like exotic microscopic seashells. Until recently the most common foram in the Sound was Elphidium excavatum, which eats diatoms. For 10,000 years diatoms were the most important microscopic algae suited to the Sound’s water temperatures and nutrient levels (including nitrogen). The marine biota that we know thrived, either directly or indirectly, on these organisms.
Historically, and up until the 1990s, E. excavatum was the dominate species of foram in the Sound. E. excavatum as well as copepods (small crustaceans eaten by many fish), rely on a diet of diatoms to maintain their population. Diatoms need not only nitrogen to grow (like other plants), but also need silica which they use to form a thin exoskeleton, just like grass contains some silica. Humans add a lot of nitrogen to the Sound from polluted runoff and sewage treatment plants, but no silica, so that ratio (N/Si) becomes unfit for diatoms to thrive so that now, other microscopic algae are out-competing diatoms. This is happening in parts of the Sound right now, especially in western Long Island Sound.
Excessive nitrogen from sewage treatment plants, polluted runoff from storm water and other sources has pushed the nitrogen-silica ratio out of whack, and thus lowered the population of diatoms available for E. excavatum. Other micro-organisms, like cyanobacteria, commonly known as blue-green algae, do not need silica to survive, and in fact many species of cyanobacteria thrive in high nitrogen environments, but these organisms are not suitable as food for many animals at the bottom of the food chain. Cyanobacteria are not a good food source for most organisms, the reason being that they’re just too small to eat.
As diatom availability drops so do populations of its consumers, eventually leaving a gap to be filled. This is where another species of foram steps up:Ammonia beccarii, which has a much wider food range. It eats diatoms andother algae. This wider diet gives A. beccarii a great advantage on E. excavatum. A. beccarii has always existed in the Sound, but in lower numbers compared to E, however, it is now becoming the dominant species in western Long Island Sound.
WHO CARES?
We do. The decreasing population of E. excavatum signifies a fundamental shift in the Sound’s food chain. Our good old, traditional E. excavatum is slipping to second place in favor of A. beccarii, the species more tolerant of excessive nitrogen levels. Small diatom-feeding organisms form the base of a food chain that begins with diatoms and ends with animals we like to eat like lobster, scallops, and many fish.
Attack of the Killer Jellyfish?
Here’s the rub: Jellyfish are one of the few organisms that have no problem eating blue green algae. Jellies can feed on smaller particles in the water. This shift in the food chain could mean jellyfish become dominant over the seafood we crave. Couple this with pH changes and warming waters and we have the stuff of a B-grade movie. Jellyfish don’t appear on many menus here…yet. They can be poisonous and, as many know, uncomfortable to swim with, to say the least. Also, jellies feed on the larval stage of many of the animals we eat, which further causes their population to drop.
These tiny forams are sending a message to us about our pollution in the Sound. Are we listening?
Foraminifera
5/4/2007
Friday, May 29, 2009
Thursday, May 28, 2009
Diatoms in the food chain
http://bayviewcompass.com/archives/960
Flood of ‘08 served up feast for fish
May 28, 2009
By Jennifer Yauck
One year ago this month, a series of severe storms moving across the Midwest dropped nearly a foot of rain on the Milwaukee area in just 10 days. The deluge caused widespread flooding that damaged homes and businesses, washed out roads, closed the airport, and belched plumes of sediment, debris, and sewage into Lake Michigan.
But the flood may also have delivered food to some of Lake Michigan’s fish when they needed it most.
Among the many things the area’s swollen rivers carried out to Lake Michigan during and after the storms was a mix of the rivers’ microscopic algae (phytoplankton), including diatoms, said Carmen Aguilar, a scientist at the Great Lakes WATER Institute. Diatoms are one of the largest forms of phytoplankton and the only form having glass-like cell walls made of silica. Diatoms also are packed with lipids, making them a nutritious meal for newly hatched fish and the tiny aquatic animals that newly hatched fish also eat.
“Compared to other phytoplankton, diatoms are like juicy steaks,” said Aguilar, who has been studying Lake Michigan’s diatoms and other phytoplankton for over a decade.
According to Aguilar, diatoms historically accounted for most of the phytoplankton found in the sun-fueled spring blooms in the Milwaukee-area waters of Lake Michigan. Those blooms typically begin in shallow, nearshore waters in late April and May, and spread to offshore waters in May and June, where they eventually sink. In the past, the diatom-rich blooms nourished the tiny animals that in turn nourished the babies of spring-spawning fish such as perch, which hatch around mid-June.
This satellite image of Lake Michigan was taken July 10, 2008, one month after the storms. The colors reflect the concentration of chlorophyll, a pigment found in phytoplankton, in the lake’s surface waters. Higher concentrations of chlorophyll (red) indicate a higher abundance of phytoplankton (most of which were diatoms in this case), while lower concentrations (blue) indicate lower abundance. The highest abundances of phytoplankton are seen at the mouths of major rivers around the lake (1-Milwaukee River drainage; 2-Two Rivers; 3-Sturgeon Canal; 4-Northern Green Bay/Death’s Door; 5-Muskegon Lake drainage; 6-Portage Lake/Frankfort drainage area). ~courtesy William Balch, Bigelow Laboratory for Ocean Science
But the makeup of the blooms began changing around 2003, according to Aguilar. That’s when the invasive quagga mussel-a voracious filter feeder with a fondness for diatoms-became well established in Lake Michigan. As a result of the quaggas’ feeding habits, the diatom population has declined significantly in recent years in the areas that Aguilar studies-within about 40 miles of Milwaukee-if not beyond.
The diatom decline, in turn, has left each year’s batch of newly hatched perch and other baby fish struggling to survive on a less nutritious diet, said Aguilar. As a result, these fish have a smaller chance of growing into adults and producing new young to sustain their populations. For an already struggling fish like perch, whose population in the Wisconsin waters of Lake Michigan dropped from a high of 23.6 million to a low of 264,000 since the early 1990s, that’s not good news.
But last year’s baby fish may have caught a break in the form of the June flood, which Aguilar said forced massive amounts of water-and diatoms-through the area’s rivers and out into Lake Michigan in a giant plume. She and her colleagues investigated the plume during a research cruise aboard the WATER Institute’s Neeskay June 10, 2008, just two days after the heaviest rains. What they found surprised them. “Outside the plume it was the same old, same old, but inside the plume there were diatoms everywhere,” said Aguilar. “Everybody was like, ‘Wow!’”
What’s more, the diatoms flourished unusually late into the summer-mid-July-and drifted unusually far-to the middle of the lake-as the plume expanded. Based on analysis of water samples for silica, the material found in diatom cell walls, and chlorophyll, a green pigment found in diatoms and other phytoplankton, Aguilar estimates some areas of the lake had two to three times more diatoms in 2008 than in 2007.
Most importantly for perch, all those diatoms entered the food web right around hatching time. Aguilar and fellow scientist Russell Cuhel suggest that such coincidences can dramatically improve baby perch survival, and may explain why some years have a “baby boom” of perch larvae. Such booms have occurred in the past during so-called El Niño years, when storms increased the lake’s turbulence and stimulated diatom growth in May and June, they said. And anecdotal reports suggest that the alewife, another Lake Michigan prey fish that also would have benefited from the 2008 influx of diatoms, reproduced in much higher numbers last year compared to other recent years.
So far, 2008 hasn’t stood out as a boom year, based on initial assessments by the Wisconsin Department of Natural Resources. But booms often do not become evident until several years later, when fish are bigger and more easily captured during assessments. Such was the case for perch born in 1998, 2002, and 2003.
Should 2008 eventually prove to be a strong year, it would provide a small boost to the diminished perch population, said Aguilar-but it would still only be a small step toward significant recovery.
Jennifer Yauck is a science writer at the Great Lakes WATER Institute. GLWI (glwi.uwm.edu) is the largest academic freshwater research facility on the Great Lakes.
AMAZING FLOOD
The Milwaukee River drains an area of almost 700 square miles before converging with the Menomonee and Kinnickinnic Rivers in downtown Milwaukee. After a series of severe rainstorms between June 5 and 14, 2008, water flowed through the Milwaukee River at a rate as high as 60,000 gallons per second, according to U.S. Geological Survey readings taken at Estabrook Park. That’s 32 times the normal June flow rate of 1,870 gallons per second!
Flood of ‘08 served up feast for fish
May 28, 2009
By Jennifer Yauck
One year ago this month, a series of severe storms moving across the Midwest dropped nearly a foot of rain on the Milwaukee area in just 10 days. The deluge caused widespread flooding that damaged homes and businesses, washed out roads, closed the airport, and belched plumes of sediment, debris, and sewage into Lake Michigan.
But the flood may also have delivered food to some of Lake Michigan’s fish when they needed it most.
Among the many things the area’s swollen rivers carried out to Lake Michigan during and after the storms was a mix of the rivers’ microscopic algae (phytoplankton), including diatoms, said Carmen Aguilar, a scientist at the Great Lakes WATER Institute. Diatoms are one of the largest forms of phytoplankton and the only form having glass-like cell walls made of silica. Diatoms also are packed with lipids, making them a nutritious meal for newly hatched fish and the tiny aquatic animals that newly hatched fish also eat.
“Compared to other phytoplankton, diatoms are like juicy steaks,” said Aguilar, who has been studying Lake Michigan’s diatoms and other phytoplankton for over a decade.
According to Aguilar, diatoms historically accounted for most of the phytoplankton found in the sun-fueled spring blooms in the Milwaukee-area waters of Lake Michigan. Those blooms typically begin in shallow, nearshore waters in late April and May, and spread to offshore waters in May and June, where they eventually sink. In the past, the diatom-rich blooms nourished the tiny animals that in turn nourished the babies of spring-spawning fish such as perch, which hatch around mid-June.
This satellite image of Lake Michigan was taken July 10, 2008, one month after the storms. The colors reflect the concentration of chlorophyll, a pigment found in phytoplankton, in the lake’s surface waters. Higher concentrations of chlorophyll (red) indicate a higher abundance of phytoplankton (most of which were diatoms in this case), while lower concentrations (blue) indicate lower abundance. The highest abundances of phytoplankton are seen at the mouths of major rivers around the lake (1-Milwaukee River drainage; 2-Two Rivers; 3-Sturgeon Canal; 4-Northern Green Bay/Death’s Door; 5-Muskegon Lake drainage; 6-Portage Lake/Frankfort drainage area). ~courtesy William Balch, Bigelow Laboratory for Ocean Science
But the makeup of the blooms began changing around 2003, according to Aguilar. That’s when the invasive quagga mussel-a voracious filter feeder with a fondness for diatoms-became well established in Lake Michigan. As a result of the quaggas’ feeding habits, the diatom population has declined significantly in recent years in the areas that Aguilar studies-within about 40 miles of Milwaukee-if not beyond.
The diatom decline, in turn, has left each year’s batch of newly hatched perch and other baby fish struggling to survive on a less nutritious diet, said Aguilar. As a result, these fish have a smaller chance of growing into adults and producing new young to sustain their populations. For an already struggling fish like perch, whose population in the Wisconsin waters of Lake Michigan dropped from a high of 23.6 million to a low of 264,000 since the early 1990s, that’s not good news.
But last year’s baby fish may have caught a break in the form of the June flood, which Aguilar said forced massive amounts of water-and diatoms-through the area’s rivers and out into Lake Michigan in a giant plume. She and her colleagues investigated the plume during a research cruise aboard the WATER Institute’s Neeskay June 10, 2008, just two days after the heaviest rains. What they found surprised them. “Outside the plume it was the same old, same old, but inside the plume there were diatoms everywhere,” said Aguilar. “Everybody was like, ‘Wow!’”
What’s more, the diatoms flourished unusually late into the summer-mid-July-and drifted unusually far-to the middle of the lake-as the plume expanded. Based on analysis of water samples for silica, the material found in diatom cell walls, and chlorophyll, a green pigment found in diatoms and other phytoplankton, Aguilar estimates some areas of the lake had two to three times more diatoms in 2008 than in 2007.
Most importantly for perch, all those diatoms entered the food web right around hatching time. Aguilar and fellow scientist Russell Cuhel suggest that such coincidences can dramatically improve baby perch survival, and may explain why some years have a “baby boom” of perch larvae. Such booms have occurred in the past during so-called El Niño years, when storms increased the lake’s turbulence and stimulated diatom growth in May and June, they said. And anecdotal reports suggest that the alewife, another Lake Michigan prey fish that also would have benefited from the 2008 influx of diatoms, reproduced in much higher numbers last year compared to other recent years.
So far, 2008 hasn’t stood out as a boom year, based on initial assessments by the Wisconsin Department of Natural Resources. But booms often do not become evident until several years later, when fish are bigger and more easily captured during assessments. Such was the case for perch born in 1998, 2002, and 2003.
Should 2008 eventually prove to be a strong year, it would provide a small boost to the diminished perch population, said Aguilar-but it would still only be a small step toward significant recovery.
Jennifer Yauck is a science writer at the Great Lakes WATER Institute. GLWI (glwi.uwm.edu) is the largest academic freshwater research facility on the Great Lakes.
AMAZING FLOOD
The Milwaukee River drains an area of almost 700 square miles before converging with the Menomonee and Kinnickinnic Rivers in downtown Milwaukee. After a series of severe rainstorms between June 5 and 14, 2008, water flowed through the Milwaukee River at a rate as high as 60,000 gallons per second, according to U.S. Geological Survey readings taken at Estabrook Park. That’s 32 times the normal June flow rate of 1,870 gallons per second!
Saturday, May 23, 2009
NOAA Eutrophication Update
http://ccma.nos.noaa.gov/publications/eutroupdate/Key_findings.pdf
"Factors influencing eutrophication (nitrogen load and susceptibility) were high for the majority of assessed systems.
"The majority of estuaries assessed had overall eutrophic conditions rated as moderate to high.
"If only assessed systems are considered, conditions have improved in 13 estuaries, worsened in 13, and remained the same in 32 systems...."
"Factors influencing eutrophication (nitrogen load and susceptibility) were high for the majority of assessed systems.
"The majority of estuaries assessed had overall eutrophic conditions rated as moderate to high.
"If only assessed systems are considered, conditions have improved in 13 estuaries, worsened in 13, and remained the same in 32 systems...."
Wednesday, May 20, 2009
Diatom Algae bloom
http://www.tcpalm.com/news/2009/may/19/algae-in-atlantic-could-move-southward-from/
Algae in Atlantic could move southward from Brevard County
By Tyler Treadway
TREASURE COAST — It looks bad, it smells bad, and it may be heading our way.
The algae floating in the Atlantic off Brevard, Flagler and Volusia counties isn't dangerous; but it deserves monitoring, say scientists.
"It's not red tide," said Cindy Heil, senior research scientist and leader of the red tide group at the Fish and Wildlife Research Institute in St. Petersburg, "that's the main thing. It's not toxic and it's not harmful."
But Brian LaPointe, a research professor at Harbor Branch Oceanographic Institute at Florida Atlantic University in Fort Pierce, said the current algae bloom could be a precursor of a red tide bloom.
Red tide can cause eye, nose and throat irritations similar to a cold. People with severe or chronic respiratory conditions are cautioned to avoid red tide areas. When red tide is present in large concentrations, it can produce toxins that kill fish. Shellfish from areas with red tide shouldn't be eaten.
"You can get what we call a series succession," said LaPointe, who's been studying algae blooms for more than 25 years. "First you have a diatom bloom like the one we're seeing now, then you see other species becoming dominant. It's not unusual for a red tide to follow a diatom bloom."
The clouds have discolored water since late April and, have been identified as the diatom algae, Thalassiosira.
"It's a single-cell plant that's the basis of the food chain," Heil said. "What's causing the problem is that there's just so many of them."
Heil said the algae isn't formed in a single mass but is "lots of little masses" that can be as small as "tens of yards across. But I've also seen them a couple of miles long."
The bloom potentially could kill sea life if it sucks up more oxygen than it produces through photosynthesis, Heil said, "but there haven't been any reports of impacts due to a net loss of oxygen."
In extremely rare instances, she added, the algae also can kill fish and shellfish by clogging their gills.
LaPointe said the recent rains along the Treasure Coast and Space Coast to the north could exacerbate the situation by flushing nutrients into coastal waters.
"Historically, red tides follow rainfall and discharges," LaPointe said, "and since we've had a drought for a while, that first flush of fresh water will be carrying a lot of nutrients."
It's possible, Heil said, that the algae blooms could travel south to the Treasure Coast.
The Treasure Coast's last outbreak of red tide, in December 2007, moved south from Volusia and Brevard counties; and the current diatom algae bloom could do the same.
"Although the Gulfstream moves south to north," Heil said, "coastal currents tend to go north to south. It gets moved around by tides and currents. It's already moved around quite a bit."
Algae in Atlantic could move southward from Brevard County
By Tyler Treadway
TREASURE COAST — It looks bad, it smells bad, and it may be heading our way.
The algae floating in the Atlantic off Brevard, Flagler and Volusia counties isn't dangerous; but it deserves monitoring, say scientists.
"It's not red tide," said Cindy Heil, senior research scientist and leader of the red tide group at the Fish and Wildlife Research Institute in St. Petersburg, "that's the main thing. It's not toxic and it's not harmful."
But Brian LaPointe, a research professor at Harbor Branch Oceanographic Institute at Florida Atlantic University in Fort Pierce, said the current algae bloom could be a precursor of a red tide bloom.
Red tide can cause eye, nose and throat irritations similar to a cold. People with severe or chronic respiratory conditions are cautioned to avoid red tide areas. When red tide is present in large concentrations, it can produce toxins that kill fish. Shellfish from areas with red tide shouldn't be eaten.
"You can get what we call a series succession," said LaPointe, who's been studying algae blooms for more than 25 years. "First you have a diatom bloom like the one we're seeing now, then you see other species becoming dominant. It's not unusual for a red tide to follow a diatom bloom."
The clouds have discolored water since late April and, have been identified as the diatom algae, Thalassiosira.
"It's a single-cell plant that's the basis of the food chain," Heil said. "What's causing the problem is that there's just so many of them."
Heil said the algae isn't formed in a single mass but is "lots of little masses" that can be as small as "tens of yards across. But I've also seen them a couple of miles long."
The bloom potentially could kill sea life if it sucks up more oxygen than it produces through photosynthesis, Heil said, "but there haven't been any reports of impacts due to a net loss of oxygen."
In extremely rare instances, she added, the algae also can kill fish and shellfish by clogging their gills.
LaPointe said the recent rains along the Treasure Coast and Space Coast to the north could exacerbate the situation by flushing nutrients into coastal waters.
"Historically, red tides follow rainfall and discharges," LaPointe said, "and since we've had a drought for a while, that first flush of fresh water will be carrying a lot of nutrients."
It's possible, Heil said, that the algae blooms could travel south to the Treasure Coast.
The Treasure Coast's last outbreak of red tide, in December 2007, moved south from Volusia and Brevard counties; and the current diatom algae bloom could do the same.
"Although the Gulfstream moves south to north," Heil said, "coastal currents tend to go north to south. It gets moved around by tides and currents. It's already moved around quite a bit."
Saturday, May 16, 2009
Beneficial freshwater algae
http://www.ecy.wa.gov/programs/wq/plants/algae/lakes/OtherFreshwaterAlgae.html
Beneficial freshwater algae
Algae are a diverse group of organisms that occur in various shapes and sizes and have different ecological roles. Thousands of species of algae occur world-wide in both fresh and marine waters. Many species of freshwater algae float in the water, but others are attached to submerged rocks or aquatic plants. Most freshwater species are inconspicuous and do not create problems for humans. There are only a dozen or so, so-called "bad actors" that are considered problem-causing algae.
Algae typically serve as an important and welcome part of a lake or pond ecosystem. They form the base of the food chain and are a vital component of lakes. Algae provide a source of food, energy, and shelter for zooplankton (tiny water animals), fish, and other lake organisms. They can play a crucial role in the ability of a ecosystem to absorb nutrients and heavy metals.
The most commonly encountered groups of freshwater algae are green algae, diatoms, and blue-green algae (more correctly known as cyanobacteria). A large and varied group called green algae are the likely ancestors of terrestrial plants. Green algae contain bright, grass-green pigments, and are more abundant than all the other groups. The cells of green algae may occur singly, as spherical colonies, or as filaments. Sometimes filamentous green algae can create problems when it grows in "cotton candy" type clouds in the water. Generally most green algae are highly palatable and a good food source for zooplankton.
Diatoms appear as yellow-green or yellow-brown algae that occur singly or more rarely in colonies. The cell wall comprises two separate valves or shells formed of silica (a major component of glass). The two shells fit together as do the two halves of a petri dish. Because of the silica valves, diatoms often occur in beautiful shapes when viewed under the microscope. Diatoms reproduce through cellular division and also sexually. Each time an existing diatom divides, the silica valves get smaller. Over time, individual cells of a diatom population become smaller and smaller. Luckily for diatoms, their sexually produced offspring are able to secrete entirely new cell walls. World-wide, diatoms provide a major food resource for zooplankton and also produce atmospheric oxygen (http://www.ucmp.berkeley.edu/chromista/diatoms/diatomlh.html). Some marine diatoms can produce a toxin called domoic acid. Domoic acid can accumulate in shellfish and poison humans http://hjs.geol.uib.no/diatoms/Hazards/index.html-ssi). Freshwater diatoms do not produce this toxin. In Washington, diatoms are often the first algae to bloom in early spring. See photographs of diatoms at: http://www.bgsu.edu/departments/biology/facilities/algae_link.html
Blue-green algae (cyanobacteria) contain green, blue, and often red pigments. Blue-greens create problems when their excessive growth produces algae blooms, and few people view them as beneficial organisms in a lake environment. Blue-green algae are discussed elsewhere on Ecology's website.
Other types of algae found in lakes include: Euglenoids, dinoflagullates, brown algae, stoneworts/brittleworts, and desmids. This list is not inclusive of all the kinds of algae that are found in freshwater. Most freshwater algae do not cause problems in lakes. Because they provide a food source for zooplankton, they tend to be rapidly consumed and rarely cause the prolonged blooms that can occur with blue-green algae.
Beneficial freshwater algae
Algae are a diverse group of organisms that occur in various shapes and sizes and have different ecological roles. Thousands of species of algae occur world-wide in both fresh and marine waters. Many species of freshwater algae float in the water, but others are attached to submerged rocks or aquatic plants. Most freshwater species are inconspicuous and do not create problems for humans. There are only a dozen or so, so-called "bad actors" that are considered problem-causing algae.
Algae typically serve as an important and welcome part of a lake or pond ecosystem. They form the base of the food chain and are a vital component of lakes. Algae provide a source of food, energy, and shelter for zooplankton (tiny water animals), fish, and other lake organisms. They can play a crucial role in the ability of a ecosystem to absorb nutrients and heavy metals.
The most commonly encountered groups of freshwater algae are green algae, diatoms, and blue-green algae (more correctly known as cyanobacteria). A large and varied group called green algae are the likely ancestors of terrestrial plants. Green algae contain bright, grass-green pigments, and are more abundant than all the other groups. The cells of green algae may occur singly, as spherical colonies, or as filaments. Sometimes filamentous green algae can create problems when it grows in "cotton candy" type clouds in the water. Generally most green algae are highly palatable and a good food source for zooplankton.
Diatoms appear as yellow-green or yellow-brown algae that occur singly or more rarely in colonies. The cell wall comprises two separate valves or shells formed of silica (a major component of glass). The two shells fit together as do the two halves of a petri dish. Because of the silica valves, diatoms often occur in beautiful shapes when viewed under the microscope. Diatoms reproduce through cellular division and also sexually. Each time an existing diatom divides, the silica valves get smaller. Over time, individual cells of a diatom population become smaller and smaller. Luckily for diatoms, their sexually produced offspring are able to secrete entirely new cell walls. World-wide, diatoms provide a major food resource for zooplankton and also produce atmospheric oxygen (http://www.ucmp.berkeley.edu/chromista/diatoms/diatomlh.html). Some marine diatoms can produce a toxin called domoic acid. Domoic acid can accumulate in shellfish and poison humans http://hjs.geol.uib.no/diatoms/Hazards/index.html-ssi). Freshwater diatoms do not produce this toxin. In Washington, diatoms are often the first algae to bloom in early spring. See photographs of diatoms at: http://www.bgsu.edu/departments/biology/facilities/algae_link.html
Blue-green algae (cyanobacteria) contain green, blue, and often red pigments. Blue-greens create problems when their excessive growth produces algae blooms, and few people view them as beneficial organisms in a lake environment. Blue-green algae are discussed elsewhere on Ecology's website.
Other types of algae found in lakes include: Euglenoids, dinoflagullates, brown algae, stoneworts/brittleworts, and desmids. This list is not inclusive of all the kinds of algae that are found in freshwater. Most freshwater algae do not cause problems in lakes. Because they provide a food source for zooplankton, they tend to be rapidly consumed and rarely cause the prolonged blooms that can occur with blue-green algae.
Wednesday, May 13, 2009
Chesapeake Bay Program - President Obama -more studies and reports
http://www.washingtonpost.com/wp-dyn/content/article/2009/05/12/AR2009051203232.html
Federal Action on the Bay
President Obama wades into the Chesapeake.
Wednesday, May 13, 2009
AS EXPECTED, the meeting of the Chesapeake Executive Council yesterday did not come up with any magical prescriptions for the deteriorating health of the bay. But it was accompanied by something new, and potentially valuable: an executive order from the president that commits the federal government to a more direct and assertive role in cleaning up the nation's largest estuary.
The Chesapeake Bay Protection and Restoration order establishes a Federal Leadership Committee to oversee and coordinate all state and federal activities to clean the waterway. Lisa P. Jackson, administrator of the Environmental Protection Agency, will lead the outfit. She will consult with Cabinet secretaries and state authorities to devise a master plan for the bay's revival. The order also commands federal agencies with land in the watershed to implement land management practices that will benefit the health of the bay. Authority under the Clean Water Act is Ms. Jackson's hammer to ensure that the goals President Obama sets out are met.
On the one hand, you could look at yesterday's meeting with a certain weariness. Officials from the federal government, along with the six states and the District of Columbia that share the bay's 64,000-square-mile watershed, promised -- surprise! -- more studies and reports. A draft report on the key challenges to protecting and restoring the bay is due within 120 days. Final reports from the Agriculture, Commerce, Defense and Interior departments are due within 180 days. A draft of the overall strategy for public comment is also due within 180 days, with the final document submitted within one year. As if nodding to the work already being done by states, including Maryland, Virginia and the District, Mr. Obama encourages them to keep going before the final strategy has been adopted. But there's been so much study of what ails the waterway that these deadlines surely could be met earlier.
On the other hand, Mr. Obama's leadership could prove to be a big deal. Not since 1984 has a president shown such concern for the sorry state of the Chesapeake Bay. That's when President Ronald Reagan mentioned it in his State of the Union address and put a dollop of money into the budget to fund what would become the Chesapeake Bay Program of the EPA. But despite that program and unending promises, conditions in the bay have only declined in the two and a half decades since. Now Mr. Obama has put the full weight of the White House behind cleaning up the historic waterway. If the effort fails this time, he'll own it.
Federal Action on the Bay
President Obama wades into the Chesapeake.
Wednesday, May 13, 2009
AS EXPECTED, the meeting of the Chesapeake Executive Council yesterday did not come up with any magical prescriptions for the deteriorating health of the bay. But it was accompanied by something new, and potentially valuable: an executive order from the president that commits the federal government to a more direct and assertive role in cleaning up the nation's largest estuary.
The Chesapeake Bay Protection and Restoration order establishes a Federal Leadership Committee to oversee and coordinate all state and federal activities to clean the waterway. Lisa P. Jackson, administrator of the Environmental Protection Agency, will lead the outfit. She will consult with Cabinet secretaries and state authorities to devise a master plan for the bay's revival. The order also commands federal agencies with land in the watershed to implement land management practices that will benefit the health of the bay. Authority under the Clean Water Act is Ms. Jackson's hammer to ensure that the goals President Obama sets out are met.
On the one hand, you could look at yesterday's meeting with a certain weariness. Officials from the federal government, along with the six states and the District of Columbia that share the bay's 64,000-square-mile watershed, promised -- surprise! -- more studies and reports. A draft report on the key challenges to protecting and restoring the bay is due within 120 days. Final reports from the Agriculture, Commerce, Defense and Interior departments are due within 180 days. A draft of the overall strategy for public comment is also due within 180 days, with the final document submitted within one year. As if nodding to the work already being done by states, including Maryland, Virginia and the District, Mr. Obama encourages them to keep going before the final strategy has been adopted. But there's been so much study of what ails the waterway that these deadlines surely could be met earlier.
On the other hand, Mr. Obama's leadership could prove to be a big deal. Not since 1984 has a president shown such concern for the sorry state of the Chesapeake Bay. That's when President Ronald Reagan mentioned it in his State of the Union address and put a dollop of money into the budget to fund what would become the Chesapeake Bay Program of the EPA. But despite that program and unending promises, conditions in the bay have only declined in the two and a half decades since. Now Mr. Obama has put the full weight of the White House behind cleaning up the historic waterway. If the effort fails this time, he'll own it.
Fish Kills in North Dakota
"Significant" Winter Fish Kills Reported in Area Lakes
By North Dakota Game and Fish Department
May 11, 2009, 10:01
BISMARCK - A long winter caused a prolonged ice pack, and coupled with near-record snowfall throughout much of the state, resulted in conditions that made it difficult for fish in some lakes to receive enough oxygen to survive.
Scott Gangl, fisheries management section leader for the North Dakota Game and Fish Department, said 37 winterkills have been confirmed so far. The majority were in the western half of the state, where lake water levels were very low going into winter.
“The winter of 2008-09 was on par with the epic winter of 1996-97, when 46 lakes experienced winterkill,” Gangl said. “Similar to that winter, all is not lost.”
Fisheries personnel have already started restocking efforts on some lakes that experienced winterkill. “We are stocking with hatchery raised fish, or fish transported from another lake with an abundance of the preferred species,” Gangl said. “These fish may take a while to grow to catchable size, but in two to three years there should be populations of fish for anglers to catch.”
The severity of a die-off may vary by lake, but usually there are some fish left in the lake. “Most of the lakes that experienced winterkill are prone to die-offs,” Gangl said. “So while there was some disappointment in losing good fisheries, there weren’t many surprises.”
Fisheries biologists are in the process of sampling suspected winterkill lakes to document the severity of the die-offs. Biologists use three levels to describe the severity of a fish kill: total, where all fish died; significant, where the game fish population is greatly reduced; or partial, where dead fish were observed but game fish are still present.
Confirmed lakes with winterkill are listed by fisheries management districts. Anglers can contact the local Game and Fish Department fisheries supervisor to get more information on the status of these lakes, or to report fish kills that may not be on the list.
North Central – Jason Lee, Riverdale, 654-7475
·North Carlson Lake, Ward County – significant
·Coal Mine Lake, Sheridan County – significant
·Cottonwood Lake, McHenry County – significant
·Crooked Lake, McLean County – significant
·South Carlson Lake, Ward County – partial
Northeast – Randy Hiltner, Devils Lake, 662-3617
·Harvey Dam, Wells County – significant
·Island Lake, Rolette County – significant
·School Section Lake, Rolette County – significant
·Sykeston Dam, Wells County - significant
Northwest – Fred Ryckman, Williston, 774-4320
·McLeod (Ray) Reservoir, Williams County – significant
·Nelson-Landers Pond, Ward County – total
·Skjermo Lake, Divide County – significant
·Stanley Reservoir, Mountrail County – total
·Tioga Dam, Williams County - total
South Central – Paul Bailey, Bismarck, 328-6688
·Beaver Lake, Logan County – significant
·Braddock Dam, Emmons County – significant
·Cherry Lake, Kidder County – significant
·Dollinger-Schnabel Lake, McIntosh County – significant
·Fresh Lake, Kidder County – significant
·Lake No. 5, Kidder County - significant
Southeast – Gene Van Eeckhout, Jamestown, 253-6480
·Crystal Springs, Stutsman County – partial
·Bisek Slough, Richland County – significant
·Boom (Marion) Lake, LaMoure County – significant
Southwest – Jeff Hendrickson, Dickinson, 227-7431
·BarZ Dam, Dunn County – total
·Cedar Lake, Slope County – significant
·Danzig Dam, Morton County – significant
·Dickinson Reservoir (Patterson Lake), Stark County – significant
·Gascoyne Lake, Bowman County – significant
·Holocek Dam, Bowman County – total
·Mirror Lake, Adams County – significant
·Odland Dam, Golden Valley County - partial
In addition, East Spring Lake Pond in Williams County, Watford City Park Pond in McKenzie County, Beach City Pond in Golden Valley County, Belfield Pond and Dickinson Dike in Stark County, and Gaebe Pond in Morton County suffered fish kills this winter. However, those ponds are stocked with catchable size fish, typically consisting of trout, sunfish or catfish. Anglers visiting these ponds may notice some dead fish, but there are recently stocked fish to catch.
http://www.ksjbam.com/artman/publish/article_1791.shtml
By North Dakota Game and Fish Department
May 11, 2009, 10:01
BISMARCK - A long winter caused a prolonged ice pack, and coupled with near-record snowfall throughout much of the state, resulted in conditions that made it difficult for fish in some lakes to receive enough oxygen to survive.
Scott Gangl, fisheries management section leader for the North Dakota Game and Fish Department, said 37 winterkills have been confirmed so far. The majority were in the western half of the state, where lake water levels were very low going into winter.
“The winter of 2008-09 was on par with the epic winter of 1996-97, when 46 lakes experienced winterkill,” Gangl said. “Similar to that winter, all is not lost.”
Fisheries personnel have already started restocking efforts on some lakes that experienced winterkill. “We are stocking with hatchery raised fish, or fish transported from another lake with an abundance of the preferred species,” Gangl said. “These fish may take a while to grow to catchable size, but in two to three years there should be populations of fish for anglers to catch.”
The severity of a die-off may vary by lake, but usually there are some fish left in the lake. “Most of the lakes that experienced winterkill are prone to die-offs,” Gangl said. “So while there was some disappointment in losing good fisheries, there weren’t many surprises.”
Fisheries biologists are in the process of sampling suspected winterkill lakes to document the severity of the die-offs. Biologists use three levels to describe the severity of a fish kill: total, where all fish died; significant, where the game fish population is greatly reduced; or partial, where dead fish were observed but game fish are still present.
Confirmed lakes with winterkill are listed by fisheries management districts. Anglers can contact the local Game and Fish Department fisheries supervisor to get more information on the status of these lakes, or to report fish kills that may not be on the list.
North Central – Jason Lee, Riverdale, 654-7475
·North Carlson Lake, Ward County – significant
·Coal Mine Lake, Sheridan County – significant
·Cottonwood Lake, McHenry County – significant
·Crooked Lake, McLean County – significant
·South Carlson Lake, Ward County – partial
Northeast – Randy Hiltner, Devils Lake, 662-3617
·Harvey Dam, Wells County – significant
·Island Lake, Rolette County – significant
·School Section Lake, Rolette County – significant
·Sykeston Dam, Wells County - significant
Northwest – Fred Ryckman, Williston, 774-4320
·McLeod (Ray) Reservoir, Williams County – significant
·Nelson-Landers Pond, Ward County – total
·Skjermo Lake, Divide County – significant
·Stanley Reservoir, Mountrail County – total
·Tioga Dam, Williams County - total
South Central – Paul Bailey, Bismarck, 328-6688
·Beaver Lake, Logan County – significant
·Braddock Dam, Emmons County – significant
·Cherry Lake, Kidder County – significant
·Dollinger-Schnabel Lake, McIntosh County – significant
·Fresh Lake, Kidder County – significant
·Lake No. 5, Kidder County - significant
Southeast – Gene Van Eeckhout, Jamestown, 253-6480
·Crystal Springs, Stutsman County – partial
·Bisek Slough, Richland County – significant
·Boom (Marion) Lake, LaMoure County – significant
Southwest – Jeff Hendrickson, Dickinson, 227-7431
·BarZ Dam, Dunn County – total
·Cedar Lake, Slope County – significant
·Danzig Dam, Morton County – significant
·Dickinson Reservoir (Patterson Lake), Stark County – significant
·Gascoyne Lake, Bowman County – significant
·Holocek Dam, Bowman County – total
·Mirror Lake, Adams County – significant
·Odland Dam, Golden Valley County - partial
In addition, East Spring Lake Pond in Williams County, Watford City Park Pond in McKenzie County, Beach City Pond in Golden Valley County, Belfield Pond and Dickinson Dike in Stark County, and Gaebe Pond in Morton County suffered fish kills this winter. However, those ponds are stocked with catchable size fish, typically consisting of trout, sunfish or catfish. Anglers visiting these ponds may notice some dead fish, but there are recently stocked fish to catch.
http://www.ksjbam.com/artman/publish/article_1791.shtml
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