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Sunday, September 30, 2012 | By Science
[MARINE_BIOLOGY_INTERNATIONAL] Fish to shrink as global warming leaves them gasping for oxygen
| By Science
Oslo, NORWAY - Fish are likely to get smaller on average by 2050 because global warming will cut the amount of oxygen in the oceans in a shift that may also mean dwindling catches, according to a study on Sunday.
Average maximum body weights for 600 types of marine fish, such as cod, plaice, halibut and flounder, would contract by 14-24 percent by 2050 from 2000 under a scenario of a quick rise in greenhouse gas emissions, it said.
"The reductions in body size will affect whole ecosystems," lead author William Cheung of the University of British Columbia in Canada, told Reuters of the findings in the journal Nature Climate Change.
His team of scientists said a trend towards smaller sizes was "expected to have large implications" for ocean food webs and for human "fisheries and global protein supply."
"The consequences of failing to curtail greenhouse gas emissions on marine ecosystems are likely to be larger than previously indicated," the U.S. and Canada-based scientists wrote.
They said global warming, blamed on human burning of fossil fuels, will make life harder for fish in the oceans largely because warmer water can hold less dissolved oxygen, vital for respiration and growth.
"As the fish grow bigger and bigger it will be difficult to get enough oxygen for growth. There is more demand for oxygen as the body grows. At some point the fish will stop growing," Cheung said of the study, based on computer models.
GASPING
As water gets warmer, it also gets lighter, limiting the mixing of oxygen from the surface layers towards the colder, denser layers where many fish live. Rising water temperatures would also add stresses to the metabolic rates of fish.
The scientists said fish stocks were likely to shift from the tropics towards cooler seas to the north and south.
Average maximum sizes of fish in the Indian Ocean were likely to shrink most, by 24 percent, followed by a decline of 20 percent in the Atlantic and 14 percent in the Pacific. The Indian Ocean has most tropical waters of the three.
The study said a computer model projected that ranges for most fish populations would shift towards the poles at a median rate of 27.5 km to 36.4 km (17.1-22.6 miles) a decade from 2000 to 2050.
Adding to climate change, other human factors "such as over-fishing and pollution, are likely to further exacerbate such impacts," they wrote.
Cheung said the shrinking of fish would have big but unknown effects on marine food chains. Predator fish like cod that swallow prey whole would become less fearsome, perhaps allowing smaller species to thrive.
"Cod ... can only eat fish that can fit into their mouth. They are not like lions or tigers" that can attack animals that are larger than they are, he said.
The climate scenario used in the study would mean an increase in world temperatures of between 2 and 5.4 degrees Celsius (3.6 to 9.7 Fahrenheit) by 2100, the second biggest gain of six scenarios used by the U.N. panel of climate experts.
"The results will be quite similar," using other scenarios, Cheung said.
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[MARINE_BIOLOGY_INTERNATIONAL] Volunteers clean up fishing line litter that can kill birds
| By Science
Volunteers clean up fishing line litter that can kill birds
Leah Palmer and Dylan Quinn, students from Sarasota High School, pick fishing line out of mangrove islands Saturday in Roberts Bay for the Sarasota Bay Watch's Annual Fishing Line Cleanup Day.
Staff photo / Shannon McFarland
By Shannon McFarland
Saturday, September 29, 2012 at 10:41 p.m.
SARASOTA COUNTY - The isolated mangrove islands in Roberts Bay are normally left alone, free from people and other animals that would disturb the host of nesting seabirds.
But in the fall, between nesting seasons, the Sarasota Bay Watch and other volunteers venture along the edge of the mangroves, searching for a nearly invisible threat to the birds — fishing line.
Equipped with gloves, scissors, trash bags and long PVC pipes with hooks at the end, the volunteers split up into groups to hunt for the deadly lines that can tangle the birds in trees and kill them.
Lee Fox, the founder of Save Our Seabirds, says that hundreds of birds are killed every year. She took a rescued pelican to show volunteers what to do if they found a live entangled bird.
About 70 people helped hunt for the fishing line, including volunteers from the Sarasota Audubon Society and a high school marine biology class.
They split into groups to clean up 23 areas, focusing on the trees and rookeries.
Kayakers checked the mangrove tunnels. Power boats traveled to remote rookeries. One larger boat ferried a group of students to several small islands, where they walked through waist-deep water along the edges of the mangroves looking for fishing line, which takes 600 years to naturally decompose in the ocean, according to the Washington, D.C.-based Ocean Conservancy.
"We really want fishermen to be more careful," said Ann Paul, a member of the Sarasota Audubon Society, as she waded in Roberts Bay.
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[MARINE_BIOLOGY_INTERNATIONAL] White Shark Diets Vary With Age and Among Individuals
Saturday, September 29, 2012 | By Science
Santa Cruz, CA — Many white sharks shift from fish to marine mammals as they mature, but individual sharks show surprising variability in dietary preferences.
White sharks, the largest predatory sharks in the ocean, are thought of as apex predators that feed primarily on seals and sea lions. But a new study by researchers at the University of California, Santa Cruz, shows surprising variability in the dietary preferences of individual sharks.
The researchers described their findings in a paper published online September 28 in PLoS ONE. They analyzed the composition of growth bands in shark vertebrae to trace variations in diet over a shark's lifetime. Stable isotopes of carbon and nitrogen incorporated into an animal's tissues serve as a natural tracer of dietary inputs.
"We did find that white shark diets changed with age, as expected, but we were surprised that the patterns and extent of change differed among individuals," said Sora Kim, who led the study as a UCSC graduate student and is now at the University of Wyoming.
The researchers analyzed vertebrae of 15 adult white sharks that had been caught along the west coast (14 off California and one off Baja California). Sharks in this population consume a wide range of prey, including seals, sea lions, dolphins, fish, and squid. But not every shark eats the same mix of prey, said coauthor Paul Koch, professor of Earth and planetary sciences at UCSC.
"We confirmed that the diets of many individuals observed at seal and sea lion rookeries shift from fish to marine mammals as the sharks mature," he said. "In addition, we discovered that different individual sharks may specialize on different types of prey. These two types of flexibility in feeding behavior are difficult to document using traditional methods, but may be very important for understanding how the population is supported by the eastern Pacific ecosystem and how it may respond to changes in that ecosystem."
The National Oceanic and Atmospheric Administration (NOAA) recently announced that it will consider whether to protect the west coast population of white sharks under the Endangered Species Act.
Tagging studies have shown that the white sharks found along the California coast have a regular migratory pattern, cruising coastal sites from late summer to early winter and moving to offshore areas during the rest of the year. While sharks within this population may have predictable movement patterns, the new study shows that there are important dietary and behavioral differences among individual sharks.
The study relied on vertebrae obtained from white shark specimens in various collections. The sharks had been caught at different times and places along the coast from 1957 to 2000. "Interestingly, we do see a small shift in diet as marine mammal populations increased after the passage of the Marine Mammal Protection Act in 1972," Kim said.
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[MARINE_BIOLOGY_INTERNATIONAL] KOI HERPESVIRUS DISEASE - UNITED KINGDOM (03): (ENGLAND)
| By Science
KOI HERPESVIRUS DISEASE - UNITED KINGDOM (03): (ENGLAND)
********************************************************
A ProMED-mail post
<http://www.promedmail.org>
ProMED-mail is a program of the
International Society for Infectious Diseases <http://www.isid.org>
Date: Mon 24 Sep 2012
Source: The Fish Site [edited]
<http://www.thefishsite.com/fishnews/18311/koi-herpesvirus-outbreak-confirmed-in-suffolk>
Movements of fish into, out of, and within a fishery in Beccles,
Suffolk, have been restricted, following the confirmation of Koi
herpesvirus.
Cefas [Centre for Environment, Fisheries & Aquaculture Science] acting
on behalf of Defra [Department of Food Environment & Rural Affairs]
has issued a confirmed designation prohibiting the movement of fish
to, from and within Henstead Fishing Lakes, Henstead, Beccles, Suffolk
and applying the following additional control measures.
Under the requirements of the designation the fishery has also been
directed to establish and maintain on-site facilities for the
disinfection of angling equipment prior to being taken out of the
designation area and anglers must comply with their use.
A sample was taken from the affected site following reported deaths of
fish showing clinical signs associated with this disease. The sample
tested positive for the presence of Koi herpesvirus.
--
Communicated by:
ProMED-mail from HealthMap Alerts
<promed@promedmail.org>
[Koi herpesvirus disease (KHD) in common carp (_Cyprinus carpio_)
disease has been reported throughout the world. The disease is
transmitted by fish to fish contact and it is also possible that the
disease can spread through contaminated water, nets and other
equipment. As other herpesviruses, KHD has the capacity to remain
latent in infected fish and become activated and cause disease when
some stressors trigger it. More information on KHD is found in OIE
Aquatic Manual chapter (2009 update), which is available at
<http://www.oie.int/fileadmin/Home/eng/Health_standards/aahm/2010/2.3.06_KHVD.pdf>.
A map of the affected area can be accessed at
<http://healthmap.org/r/3yA0> - Mod.PMB]
[Images of koi carp:
<http://upload.wikimedia.org/wikipedia/commons/thumb/9/90/Six_koi.jpg/220px-Six_koi.jpg>.
- Mod.JW]
[see also:
Koi herpesvirus disease - UK (02): (England) 20120911.1289935
Koi herpesvirus disease - USA: (MO) 20120624.1178973
Koi herpesvirus disease - UK: (England) 20120619.1173349
Koi herpesvirus disease - Sweden: (VG) OIE 20120517.1135973
Koi herpesvirus disease - Italy: (VN), OIE 20120513.1131835
2011
----
Koi herpesvirus disease - UK: (England) 20111027.3192
Die-off, carp - USA (06): (IN) koi herpes virus 20111005.2999
Koi herpesvirus disease - Spain: OIE 20110808.2408
Die-off, carp - USA (05): (MI): koi herpes virus 20110807.2386
2010
----
Koi herpesvirus disease - UK: (England) 20100828.3069
Undiagnosed fish die-off - USA (02): (NJ) koi herpesvirus susp.
20100528.1773
Koi herpesvirus, carp - USA: (CA) 20100523.1707
2009
----
Koi herpesvirus disease - UK (02): (England) 20090918.3273
Koi herpesvirus disease - UK 20090814.2893
Koi herpesvirus, carp - USA: (AZ) 20090703.2395
Koi herpesvirus disease - USA (AZ) 20090613.2186
2008
----
Koi herpesvirus disease - UK (02): (England) 20080926.3044
Koi herpesvirus disease - UK 20080908.2807
2007
----
Koi herpesvirus disease - UK (02) 20071108.3630
Koi herpesvirus disease - UK 20070817.2688]
...........................................sb/pmb/ejp/jw/ll
*##########################################################*
************************************************************
ProMED-mail makes every effort to verify the reports that
are posted, but the accuracy and completeness of the
information, and of any statements or opinions based
thereon, are not guaranteed. The reader assumes all risks in
using information posted or archived by ProMED-mail. ISID
and its associated service providers shall not be held
responsible for errors or omissions or held liable for any
damages incurred as a result of use or reliance upon posted
or archived material.
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[MARINE_BIOLOGY_INTERNATIONAL] Tiny Sea Plant Swims from Predators
| By Science
Boston, MA - A tiny marine plant has been caught acting like an animal, find scientists who discovered a species of phytoplankton, a microscopic alga, could swim away from its predators.
Their finding could shed new light on what causes some colorful plankton blooms.
"It has been well observed that phytoplankton can control their movements in the water and move toward light and nutrients," marine scientist Susanne Menden-Deuer, of the University of Rhode Island, said in a statement. "What hasn't been known is that they respond to predators by swimming away from them. We don't know of any other plants that do this."
In lab experiments, Menden-Deuer and her team observed that groups of the phytoplankton Heterosigma akashiwo flee when in the presence of predatory zooplankton. What's more, the tiny plants swim away from areas that previously contained the predators even if the immediate threat is gone.
"The phytoplankton can clearly sense the predator is there," Menden-Deuer said. "They flee even from the chemical scent of the predator but are most agitated when sensing a feeding predator."
The algae do this to stay alive. If the phytoplankton have no place to hide, they'll get eaten up by their zooplankton predators within a day. But the algae double in population every two days if they have a refuge, the researchers said. If the same is true for other species of phytoplankton, this discovery could offer a new explanation for some plankton blooms.
"One of the puzzling things about some phytoplankton blooms is that they suddenly appear," Menden-Deuer said. "Growth and nutrient availability don't always explain the formation of blooms. Our observation of algal fleeing from predators is another mechanism for how blooms could form. Amazingly, looking at individual microscopic behaviors can help to explain a macroscopic phenomenon."
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Amil Saude com preco incomparavel
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Email notifications from Google Webmaster Tools
| By Science
Dear Webmaster Tools user,
We know that having a healthy and well-performing website is important to you. To keep you informed about your site's status Webmaster Tools will now automatically send you a notification email if there are critical or important issues that we detect with your site.
We'll only send you email for issues that we think have significant impact on your site's health or search performance which have clear actions that you can take to address. For example, we'll email you if we detect malware on your site or see a significant increase in errors while crawling your site.
For most sites these kinds of issues will occur rarely. If your site does happen to have an issue we cap the number of emails we send over a certain period of time to avoid flooding your inbox.
If you don't want to receive any email from Webmaster Tools you can change your email delivery preferences at https://www.google.com/webmasters/tools/preferences.
We hope that you find this change a useful way to stay up-to-date on critical and important issues regarding your site's health.
If you'd like more information about Webmaster Tools and building Google-friendly websites please visit http://www.google.com/webmasters.
The Webmaster Tools Team
© 2012 Google Inc. 1600 Amphitheatre Parkway, Mountain View, CA 94043
You have received this mandatory email service announcement to update you about important changes to your Google Webmaster Tools account.
[MARINE_BIOLOGY_INTERNATIONAL] PETA sues Sea World over killer whale's injury
Friday, September 28, 2012 | By Science
SAN DIEGO (CNS) - Officials of People for the Ethical Treatment of Animals announced Friday they have filed a complaint with the Department of Agriculture for conditions at SeaWorld San Diego that led to a gaping injury to the lower jaw of an 11-year-old killer whale.
A SeaWorld statement said the whale, a male named Nakai, was injured during a nighttime performance Sept. 20, but did not make clear how the injury occurred.
"Nakai is currently receiving antibiotics and the veterinarians are pleased with the healing progress of his wound," the statement read.
Despite the injury, the whale is "swimming comfortably and interacting with other killer whales" in the Shamu Stadium pool complex at the marine park, officials said.
PETA, however, contends on its blog, the "PETA Files," that a whistleblower said Nakai was attacked by two other orcas, Keet and Ikaika.
In the complaint to the Agriculture Department, PETA said it wants SeaWorld disciplined for not keeping the whales separated as required under the Animal Welfare Act. According to PETA, the law requires incompatible marine mammals to be kept in separate enclosures.
SeaWorld San Diego did not immediately respond to a message seeking comment on PETA's allegations.
U-T San Diego quoted Dr. Nancy Anderson, a veterinarian with the University of California Davis Wildlife Center and a former veterinarian at Six Flags Discovery Kingdom, as saying Nakai's injury was too smooth to have been caused by another orca, and was more consistent with getting snagged on something and trying to pull away.
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[MARINE_BIOLOGY_INTERNATIONAL] Whale of a Tale: Sir Arthur Conan Doyle's Arctic Adventure
| By Science
LONDON - The surgeon aboard the whaling vessel Hope was often covered in the blood of seals and other animals, his clothes frozen enough that he'd have to stand next to the ship's stove to thaw before undressing.
A first-time sailor, he wasn't supposed to take part in the clubbing of seals, but he did, and repeatedly fell into the frigid waters, nearly freezing to death.
A journal by the young man, written at age 20 in 1880, was published yesterday. The author? Sir Arthur Conan Doyle.
Best known for creating the ingenious detective Sherlock Holmes, Doyle was first a surgeon, and went along on the whaling ship after a friend of his backed out, according to a review of the book by the Daily Mail.
The journey was intense and bloody, and the sailors' job was to take as many seals and whales as possible. As noted by the Smithsonian, though, Doyle's journal of the trip isn't all blood and gore, and contains Doyle's neat prose and lovely illustrations of the ship and the terrain it explored in the Arctic Ocean.
The killing of whales was common at the time, although Doyle did write about his feelings of sympathy for the hunted animals. He also describes the beauty of the icy landscape and awe he felt upon seeing enormous humpback whales, which the sailors didn't hunt because they contained too little oil to make their capture worthwhile. Whale oil was valuable for its use in lamps, candle wax and other applications.
Doyle wrote about his experience in both fiction and nonfiction, which helped him first catch the eye of publishers. Although he completed medical school and briefly practiced as a surgeon, he soon realized his true talent lay in writing.
The account of his Arctic voyage is called "Dangerous Work: Diary of an Arctic Adventure" (British Library Publishing, 2012) and is available from the British Library Shop.
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[MARINE_BIOLOGY_INTERNATIONAL] Gator that tore off woman's arm caught, killed
Thursday, September 27, 2012 | By Science
Gator that tore off woman's arm caught, killed
Trappers bring out a dead gator from the canal. FWC believes this is the gator that attacked the woman.
Thursday, September 27, 2012
.LEESBURG --
Florida Fish and Wildlife Conservation Commission officers believe they have the gator that attacked an elderly Lake County woman.
Carol Huff, 84, was standing on her back deck at her home on Hubbard Street when she fell into the canal around 7:15 a.m. Wednesday.
Officers said she was attacked by an 8-foot alligator.
Huff's neighbor, Del Zickefoose, was drinking his morning coffee when he saw the woman in distress in the water.
Zickefoose jumped in, pulled her to safety and held her until emergency responders arrived.
"As I was bringing her to the shore, I noticed her arm was gone," said Zickefoose. "Completely gone. It was just flesh hanging, and pieces of bone hanging out the side. I was at the right place, the right person at the right time. Another five minutes, and she would have been gone."
He said he didn't realize it was an alligator that attacked her until she repeated the word gator to him.
Deputies said many homes in the community have water behind them, and alligators are seen every day in the canal.
"They're there every day, up and down the canal. They're just part of the community," said Mary Weaver, who lives nearby. "There's nothing to be afraid of, but sometimes accidents happen."
FWC officers said they recovered parts of her arm, but some is still missing.
Officers say a necropsy of the dead gator found none of the woman's arm, but they did find pieces of hamburger, which proves someone was feeding the animal.
That's against the law in Florida, because gators will lose their fear of humans.
Even though they did not find any part of Huff's arm inside the gator, they believe this animal attacked her.
FWC said alligator attacks are rare, but do happen.
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[MARINE_BIOLOGY_INTERNATIONAL] Scientists Capture Clues to Sustainability of Fish Populations
| By Science
Santa Barbara, CA — Thanks to studies of a fish that gives birth to live young and is not fished commercially, scientists at UC Santa Barbara have discovered that food availability is a critical limiting factor in the health of fish populations.
The scientists were able to attach numbers to this idea, based on 16 years of data. They discovered that the availability of enough food can drive up to a 10-fold increase in the per capita birthrate of fish. And, with adequate food, the young are up to 10 times more likely to survive than those without it.
This research, published this week in the Proceedings of the Royal Society B, is expected to be useful for managers involved in maintaining sustainable fisheries.
The scientists used a remarkable set of black surfperch population data -- collected from 1993 to 2008 -- to develop these statistics. Divers collected the data by monitoring a fish population off Santa Cruz Island, near Santa Barbara. Russell J. Schmitt and Sally J. Holbrook, both professors in UCSB's Department of Ecology, Evolution, and Marine Biology and UCSB's Marine Science Institute, head the team of scientists.
First author Daniel K. Okamoto, a Ph.D. student in UCSB's Department of Ecology, Evolution, and Marine Biology, explained that there has been a lack of information about how survival and birthrates are influenced by food availability, which is known to fluctuate through time. Black surfperch, found off the Pacific Coast from central Baja California northward to Fort Bragg, feed on small crustaceans and worms.
"If a management procedure has called for a certain harvest rate that is constant through time, that would be like saying we should harvest the same amount of corn through time, even though we know that corn can be influenced by things like drought," said Okamoto.
The scientists consider the black surfperch (Embiotoca jacksoni) to be a model species because it is not fished commercially, making it easier to assess the effects of food availability on fish mortality and reproduction.
A key feature of the black surfperch is the fact that this fish gives birth to live young that remain on the reef, allowing for its population to be counted accurately from year to year.
"The individual fish stay on their natal reef; they have low emigration- immigration rates, so we can actually track cohorts through time," said Okamoto. "An adult gives birth to live, capable young, instead of laying eggs. Those young stay on the reef where the adults were, which is a really nice property. We can go to a reef in a given year, survey it for adults, then go to that reef again the next year and see the young that are there and know, for the most part, that those young came from the adults that were there the year before." By contrast, most fish are dispersed into open water when they are in the larval stage.
Okamoto said that not including food availability in calculating benchmarks for species conservation may leave out a critical element in fisheries management.
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[MARINE_BIOLOGY_INTERNATIONAL] Rare whale frolics off Australian coast
| By Science
Cape Byron, QL (Australia) - It may seem straight out of Moby Dick, but a rare white whale is thrilling Australians off the eastern coast.
The albino humpback has been nicknamed "Migaloo" by researchers who track his movements.
Albino whales are rare and Migaloo is the only documented all-white humpback adult, according to Peter Harrison, director of marine ecology research at Southern Cross University in Australia.
Peanut butter recall expanded Migaloo was first seen in 1991 when he was a juvenile, Harrison says, and researchers believe he is now in his 20s.
The humpbacks are on their annual migration from their breeding grounds along the Great Barrier Reef back to feed in the Antarctic.
"Everyone here is quite excited," says Oskar Peterson, who runs a website that tracks sightings of white whales around the globe. "We see him almost every year now, but it's still front page news when he turns up."
Migaloo is expected to pass by Cape Byron, the easternmost point in Australia, in the coming hours after passing by Surfer's Paradise, Peterson says. Spotters of the whale share sightings at his website
Male humpbacks can travel up to 140 kilometers (87 miles) a day during their migration, according to experts.
But they often hang around Cape Byron searching for mates, so whale watchers may see the albino humpback for a few more days, Harrison says.
He warns fans to steer clear -- at least 500 meters away at all times -- to ensure the whale's survival. Too much noise and chasing can disturb him and cause him to use precious energy he needs for migration.
Whale watchers may be able to enjoy Migaloo for decades. Humpback whales are believed to survive as long as 90 years in the wild, Harrison says.
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[MARINE_BIOLOGY_INTERNATIONAL] DIE-OFF, FISH - USA: (TEXAS) LAKE INVERSION SUSPECTED
| By Science
DIE-OFF, FISH - USA: (TEXAS) LAKE INVERSION SUSPECTED
*****************************************************
A ProMED-mail post
<http://www.promedmail.org>
ProMED-mail is a program of the
International Society for Infectious Diseases <http://www.isid.org>
Date: Mon 17 Sep 2012
Source: kristv.com [edited]
<http://www.kristv.com/news/6-investigates-mass-fish-death/>
We have new information about the fish kill we reported at Lakeview Park yesterday [16 Sep 2012]. The Texas Department of Parks and Wildlife met 6 News at the site this morning [17 Sep 2012] after we called them. They took samples of the water to test it and see what may have caused this large fish kill.
So far, officials have concluded that the fish died due to a lack of oxygen in the water. However, until their tests are fully complete, they won't know exactly what caused the low oxygen levels.
We talked with Dr Larry McKinney, a marine biologist at Texas A&M Corpus Christi about the fish kill. He offered up several possible explanations as to what may have happened to these fish. He says the most likely cause may be something called lake turnover.
Lake turnover occurs in ponds and lakes. Typically, in a climate like Corpus Christi's, ponds and lakes have warm water on top with high levels of oxygen and cold water at the bottom with low levels of oxygen. When a cold front comes through, like the rain we've just had, the water levels mix. That causes the overall oxygen level to drop and the fish can't breath.
"It's likely a natural phenomenon. When the temperature gets right and the conditions are right, these things do happen," Dr McKinney says.
He added that other possibilities include pollution from runoff into the waterway and diseases spreading from fish to fish.
Whatever the reason, regular visitors to the park are stunned. A local man has been coming to the pond for 30 years and can't believe what's happened. He had just one question. "What's really wrong with the water? I've never seen it like this," he says.
Texas Parks and Wildlife officials hope to have more answers to that question soon.
[Byline: Andrew Ellison]
--
Communicated by:
ProMED-mail from HealthMap alerts
<promed@promedmail.org>
[A naturally occurring temperature inversion might bring an oxygen-depleted layer of water from the bottom of a lake close to its surface. The density of water depends on its temperature, and water is at its densest at around 4 deg C (39.2 deg F). Water that is colder or warmer than 4 degrees will be 'lighter', and will tend to move upwards. This property of water makes it tend to form into layers.
There is less oxygen in deeper layers. In a lake, the interface between those layers is known as a thermocline. If water at the surface changes, approaching 4 deg C, it will sink downwards.
A map of the affected area can be accessed at <http://healthmap.org/r/3vBj>. - Mod.PMB]
[Thermocline diagram:
<http://www.fishingreports.com/wp-content/uploads/2012/05/thermocline-fishing.jpg>.
- Mod.JW]
[see also:
Die-off, fish - Canada: (ON) lake inversion susp 20120909.1287307 Die-off, fish - USA (06): (OH) RFI 20120827.1266581 Die-off, fish - USA (02): (GA) comment 20120601.1153265 Die-off, fish - USA: (GA) pollution susp. 20120531.1152141
2011
----
Undiagnosed die-off, fish - USA (02): (GA) columnaris 20110528.1641 2010
----
Undiagnosed fish die-off - USA (04): (WV, OH, PA) columnaris 20100610.1946] .................................................sb/pmb/mj/jw/ll
*##########################################################*
************************************************************
ProMED-mail makes every effort to verify the reports that are posted, but the accuracy and completeness of the
information, and of any statements or opinions based
thereon, are not guaranteed. The reader assumes all risks in
using information posted or archived by ProMED-mail. ISID
and its associated service providers shall not be held responsible for errors or omissions or held liable for any damages incurred as a result of use or reliance upon posted or archived material.
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