algal bloom

Craig Brennan, right, hauls an 18-inch smallmouth bass out of the Susquehanna River Monday at Long Level while Austin Schmitt continues his search in this November 2010 file photo. (FILE PHOTO)
Over the past decade, the decline of one of the most prized freshwater sport-fish species -- the smallmouth bass -- has puzzled anglers and scientists.
Populations that once thrived throughout the Chesapeake Bay watershed -- including the lower Susquehanna River -- have experienced fishkills and perplexing illnesses, according to a recent report from the Chesapeake Bay Foundation.
The problems include lesions, blotchy skin, shorter lifespans and abnormal sexual development in which males grow eggs in their testes, said Harry Campbell, the foundation's Pennsylvania executive director.
A myriad of influences are coming together to threaten the smallmouth bass, Campbell said. Phosphorus and nitrogen pollution have been linked to spring algal blooms that create low-oxygen conditions that stress fish.
"These algae blooms occur when our smallmouth fry are most vulnerable to infection," said John Arway, executive director of the commission in a conference call hosted by the foundation.
Younger populations of smallmouth bass are dying at "unprecedented rates," Campbell said.
With shorter lifespans for adults and juveniles not living to adulthood, the overall population is feared to be near collapse, he said.
The loss of this species will have serious environmental and economic impacts, Campbell said.
Smallmouth bass fishing in Pennsylvania generates $166 million for local economies,
Advertisement
supporting 1,300 jobs, according to data from the American Sportfishing Associations and the U.S. Fish and Wildlife Service. In the Susquehanna River, smallmouth bass populations have plummeted, with catch rates of adults falling 80 percent between 2001 and 2005, according to the Pennsylvania Fish and Boat Commission.
Subsequent studies by the commission have found that populations have not recovered.
This decline prompted the state agency to impose emergency regulations that prohibited fishing for the species in much of the river from May 1 to June 15, 2012, and again this year.
The Bay Foundation and others petitioned the DEP to list the lower Susquehanna as impaired because of ongoing disease and decline of the smallmouth bass.
The EPA recently approved the state Department of Environmental Protection's 2012 Impaired Waters List.
According to the report, the lower Susquehanna was deemed to have "insufficient water quality data to make an impairment determination."
Campbell and Arway said they will continue to push for investment in programs and policies that address the issues facing the smallmouth bass populations.
"Our fish are sick, our anglers are mad and my board and I, protectors of our fishery, are frustrated," said Arway. "We need Environmental Protection Agency leadership to drive the issues since it is a regional problem of national significance."

ANOTHER two dead dolphins were found on South Australia's coastline at the weekend as post-mortem results released today reveal another three dead dolphins from Gulf St Vincent tested positive for morbillivirus.

The virus is related to measles in dogs and humans and cannot be transmitted between species.
The latest juvenile dead dolphins were found at O'Sullivans Beach yesterday and Port Broughton in Spencer Gulf on Saturday, bringing the state's total to 31 since March 1.
Environment Department Chief Executive Allan Holmes said the outbreak of the virus could be the cause of the unusual spate of dolphin deaths.
"Morbillivirus can be spread through close contact between dolphins, including between mother and newborn," he said.

Mr Holmes said the virus had previously been found in dolphins in Queensland and Western Australia.
"It is a natural virus and outbreaks occur from time to time, with surviving animals developing immunity," he said.
"It is not associated with the recent algal bloom, but may be related to the warmer water temperatures that also caused the bloom."
Mr Holmes yesterday assured the public there were several thousand dolphins living in Gulf St Vincent and said the species was not under threat. 
Gallery: Adelaide's dead fish mystery

A rise in the number of deaths of dolphins along local beaches in South Australia had concerned experts. While they could not find what caused a total of 25 dolphins' deaths in recent weeks, the fatalities now are being linked to a virus.
The virus, reportedly, was not detected earlier in the region. But, Lucy Woolford, veterinary pathologist, has reported that a systemic fungal infection as well as the morbillivirus has been found in tests of two young dolphins.
The report finds that Dolphin morbillivirus (DMV) has been detected earlier as well in juvenile dolphins' deaths in Western Australia, Queensland and northern NSW. The virus has also been held responsible for the deaths of whales and dolphins overseas.
According to Dr. Woolford's statement, the latest findings have added to concerns that more animals could also face such consequences. A large number of small fish have also been found washed ashore along different parts of the SA coastline.
A wider investigation was called by the discovery and it concluded that an algal bloom produced by unseasonal winds was probably the cause.
"We don't know how big an impact it will have on the local dolphin population, whether it will be sporadic cases or become more widespread", avowed Dr. Woolford.

A virus not previously detected in South Australia has been blamed for a spate of dolphin deaths along local beaches.

Veterinary pathologist Lucy Woolford said the morbillivirus and a systemic fungal infection had been detected in two of the young dolphins tested.
They were among 25 found dead and washed up in recent weeks.
She said the discovery raised concerns that more of the animals could die in coming months.
"We don't know how big an impact it will have on the local dolphin population, whether it will be sporadic cases or become more widespread," Dr Woolford said.
Dolphin morbillivirus (DMV) has previously been implicated in the death of juvenile dolphins in Queensland, northern NSW and Western Australia.
Overseas it has been thought to be the cause of die-offs of whales and dolphins.
Around the same time as the dolphin deaths, tens of thousands of small fish also washed up dead along various parts of the SA coastline.
That sparked a wider investigation with scientists later attributing the fish deaths to an algal bloom sparked by unseasonal winds.

The South Australian Government says it has discovered the reason for fish recent mass fish deaths, saying an algal bloom is to blame, but it has been unable to pinpoint why so many young dolphins have died.
Thousands of dead fish have been washing up on beaches across the state since March, causing concern among beachgoers.
The SA Government says new satellite images confirmed that warm ocean temperatures and nutrient upwelling triggered the algal blooms responsible for the deaths.
"It is a physical trapping of the algae in the gills, the algae irritate the gills, the fish responds by forming mucus, and the mucus effectively stops oxygen transportation across the gills," Dr Rob Rahaley from Primary Industries said.
Minister for Fisheries Gail Gago said the bloom has likely dispersed and there is no risk to public health.
"This algal bloom is not producing any toxins that could be dangerous to human beings," she said.
While the fish mystery has been solved, authorities are yet to pinpoint the cause of 26 dolphin deaths in recent weeks.
Test results are in for six of the dolphins, showing four of them had a fungal pneumonia which also spread to their brains, which their immune system would normally fight off.
"Why are the dolphins, apparently, suddenly becoming susceptible to it?" dolphin researcher Dr Mike Bossley asked.
"Is there something that's made them more vulnerable?"
The Government says that is being investigated.
"There's no denying there is something that's put those dolphins into a situation where their immune system is compromised, we haven't found that underlying cause yet," Dr Rahaley said.
The Government says samples have also been sent to an animal health laboratory in Geelong to test for viruses.

The South Australian Government insists it in not downplaying a statewide marine crisis after the discovery of thousands more dead fish and another three dolphin carcasses.
Almost a fortnight ago, authorities believed the worst was behind us, but many beachgoers are growing increasingly skeptical.
Thousands of dead fish have washed up on South Australian beaches in recent weeks, along with dolphins and some penguins.
Most recently, a young dolphin carcass was discovered by a surf school at Southport this morning, while a dead dolphin calf was spotted in the Port River yesterday, being pushed along by its grieving mother.
Marine biology PhD student Nikki Zanardo told 7News: "We need to work out what it is, at this stage we are still unsure."
Theories range from water temperature to algal blooms and even dodge tides, but locals are not convinced.
Samples from some of the dead dolphins have been sent to New Zealand for testing.
BioSecurity SA won't say why they weren't all carried out locally.
"Well they're looking for biological toxins, bio-toxins as they call them," Vic Neveraskus from Biosecurity SA said.
He has reassured seafood customers not to be alarmed.
"I'm not at all nervous," he said.
But with autopsy results on the dolphins still weeks away and more marine life dying, authorities are scratching their heads for clues in the ongoing marine mystery.
"Dolphins, they're not much smaller than us and they're washing up dead on our shores, so yeah, it's horrible to think what it's doing to our health," surfer Rebecca Wissell said.

Lake Victoria is under threat and the very people this water source is supposed to serve are the ones threatening its existence. Today, let's explore why the Nile Perch is almost non-existent in the lake.
By Mathias Mugisha
More fish factories will close, turning fishermen into economic refugees. Out of the over 20 fish factories in Uganda, only 15 are still operational. In Jinja, two of the four factories have closed down. All the factories are operating below capacity.
Overfishing, catching immature fish, environmental degradation and pollution on Lake Victoria are killing the Nile perch, which forms the backbone of commercial fishing.
The young fish are starving and suffocating to death. The National Fisheries Resources Research Institute (NaFIRRI) predicts doom if nothing changes.
Information from NaFIRRI indicates that micro-organisms in the lake on which the young fish feed are also dying. This is brought about by the floating algae bloom on the lake that is poisoning the fish and cutting off oxygen supply to marine life.
Elias Muhumuza, a research technician at NaFIRRI, says Nile perch needs a lot more space and dissolved oxygen than other fish.
The lake is dying along with fish because of over fertilisation (eutrophication). This is the process by which a water body becomes rich in dissolved nutrients from fertilisers or sewage, thereby encouraging the growth and decomposition of oxygen — depleting plant life like algae and harming other organisms in the lake.
Algal blooms are normally a result of water pollution (normally caused by untreated waste from industrialisation, urbanisation and agriculture) which are normally experienced in some bays of Lake Victoria like Kitubulu and Murchison bay.
This has an effect on fish and other organisms in the water because the over-growth of algae due to a lot of nutrients and presence of suspended solids in the water reduces light penetration/ transparency, which has a lot of negative effects on all aquatic organisms.
Decomposition/decay of dead algae or other organisms consumes a lot of oxygen and hence competes with the fish, their prey and other aquatic organisms for dissolved oxygen, affecting the stability of the whole aquatic ecosystem.
“The result from the above scenarios is that the fish will die or will be under stressful conditions (due to lack of oxygen and food), meaning they will not be able to reproduce and grow well (the survivors), hence reduced stocks.

A man offloads smuggled fish from neighbouring Tanzania. PHOTO/Mathias Mugisha
Most young Nile perch stay in shallow waters near the shores to avoid high winds and being eaten by bigger Nile perch.
Nile perch is dying young because the organisms the fish feeds on also die,” explains Muhumuza.
Records from NaFFIRI show that the Nile perch has declined from an average of 1.2 million tonnes from 1999 to 2007, to about 800,000 today; while silver fish (mukene) has increased from about 400,000 to one million tonnes over the same period.
Other groups, mainly Nile tilapia (ngegge) and haplochromines (nkejje) have increased from 300,000 to about 600,000 tonnes. However, the trends show that when you compare the two, nkejje seems to have increased while ngegge declined.
“The increase in the smaller fish species is attributed to the decrease on the Nile perch which preys on them. Nile perch is the top predator. Once the number of predators goes down, its prey increases,” says Muhumuza.
Currently, mukene accounts for about 70% of Lake Victoria biomass, overtaking nkejje which accounted for 80% of the lake biomass when the Nile perch was introduced into Lake Victoria in the 1950s and 1960s for sport fishing.
The Nile perch (Latesniloticus) is a species of freshwater fish in the Latidae family of the order Perciformes. The
Nile perch can weigh up to 250kg with an average length of a mature fish averaging 121-137cm (48-54 inches), although many fish are caught before they can grow this large.
Though the introduction of the Nile perch was an ecological disaster that has led to the extinction of some of the indigenous fish species, it increased fish stocks in the lake 10 times, according to NaFFIRI.
The Nile perch was introduced along with two other tilapia species to boost the indigenous tilapia stocks in Lake Victoria which had declined.
The indigenous tilapia has since become extinct.

The pollution on the lake has also greatly affected the fish species.
According to Dr. Dismus Muhumuza, head of aquaculture research at NaFIRRI, the Nile perch was brought with four foreign tilapia species namely: Oreochromis niloticus, Tilapia zillii, Tilapia rendalli and Oreochromis leucostictes.
These species competed with the native tilapia species of Oreochromis variabilis and Oreochromis esculentus as the Nile perch hunted both of them with its biggest appetite directed at the nkejje.
Today figures from NaFIRRI show that Oreochromis variabilis is rare while Oreochromis esculentus is extinct.
The alteration of the native ecosystem had disruptive socioeconomic effects on local communities bordering the lake. Large-scale fishing operations, while earning millions of dollars from exports, have displaced many local people from their traditional occupations in the fishing trade and brought them to fishing villages where scarcity of fish has turned them into economic refugees.
On the flipside, Nile perch stimulated the establishment of large fishing companies and boosted sport fishing tourism in the region, with Murchison Falls considered one of the best fishing destinations in the world.
Every year, anglers from all over the world converge here to hook out Nile perch, weigh the fish and take their pictures with the catch, before releasing them back into the water.
But now, the tide has turned against the Nile perch, with man as its greatest enemy, threatening its existence and the livelihoods of the over 30 million people who depend on Lake Victoria.
“If this trend continues, more factories will have no choice but to close. There will simply be no fish left to sustain the factories,” Muhumuza concludes.

The statements, comments, or opinions expressed through the use of New Vision Online are those of their respective authors, who are solely responsible for them, and do not necessarily represent the views held by the staff and management of New Vision Online.
New Vision Online reserves the right to moderate, publish or delete a post without warning or consultation with the author.Find out why we moderate comments. For any questions please contact digital@newvision.co.ug

KAMPALA, April 15 (BERNAMA-NNN-NEW VISION) -- More fish factories in Uganda will soon close, turning fishermen into economic refugees. Out of the over 20 fish factories in Uganda, only 15 are still operational. In Jinja, two of the four factories have closed down. All the factories are operating below capacity.
Overfishing, catching immature fish, environmental degradation and pollution of Lake Victoria are killing the Nile perch, which forms the backbone of commercial fishing in landlocked Uganda.
The young fish are starving and suffocating to death. The National Fisheries Resources Research Institute (NaFIRRI) predicts doom if nothing changes.
Information from NaFIRRI indicates that micro-organisms in the lake, the continent's largest, on which the young fish feed are also dying. This is brought about by the floating algae bloom on the lake that is poisoning the fish and cutting off oxygen supply to marine life.
Elias Muhumuza, a research technician at NaFIRRI, says the Nile perch needs a lot more space and dissolved oxygen than other fish.
The lake is dying along with fish because of over fertilization (eutrophication). This is the process by which a water body becomes rich in dissolved nutrients from fertilizer or sewage, thereby encouraging the growth and decomposition of oxygen -- depleting plant life like algae and harming other organisms in the lake.
Algal blooms are normally a result of water pollution (normally caused by untreated waste from industrialisation, urbanisation and agriculture) which are normally experienced in some bays of Lake Victoria like Kitubulu and Murchison Bay.
This has an effect on fish and other organisms in the water because the over-growth of algae due to a lot of nutrients and presence of suspended solids in the water reduces light penetration/ transparency, which has a lot of negative effects on all aquatic organisms.
Decomposition/decay of dead algae or other organisms consumes a lot of oxygen and hence competes with the fish, their prey and other aquatic organisms for dissolved oxygen, affecting the stability of the whole aquatic ecosystem.
"The result from the above scenarios is that the fish will die or will be under stressful conditions (due to lack of oxygen and food), meaning they will not be able to reproduce and grow well (the survivors), hence reduced stocks.
Most young Nile perch stay in shallow waters near the shores to avoid high winds and being eaten by bigger Nile perch.
"The Nile perch is dying young because the organisms the fish feeds on also die," explains Muhumuza.
Records from NaFFIRI show that the Nile perch has declined from an average of 1.2 million tonnes from 1999 to 2007, to about 800,000 today; while silver fish (mukene) has increased from about 400,000 to one million tonnes over the same period.
Other groups, mainly Nile tilapia (ngegge) and haplochromines (nkejje) have increased from 300,000 to about 600,000 tonnes. However, the trends show that when you compare the two, nkejje seems to have increased while ngegge declined.
"The increase in the smaller fish species is attributed to the decrease on the Nile perch which preys on them. Nile perch is the top predator. Once the number of predators goes down, its prey increases," says Muhumuza.
Currently, mukene accounts for about 70 per cent of Lake Victoria biomass, overtaking nkejje which accounted for 80 per cent of the lake biomass when the Nile perch was introduced into Lake Victoria in the 1950s and 1960s for sport fishing.
The Nile perch (Latesniloticus) is a species of freshwater fish in the Latidae family of the order Perciformes. The Nile perch can weigh up to 250 kg with an average length of a mature fish averaging 121-137cm (48-54 inches), although many fish are caught before they can grow this large.
Though the introduction of the Nile perch was an ecological disaster that has led to the extinction of some of the indigenous fish species, it increased fish stocks in the lake 10 times, according to NaFFIRI.
The Nile perch was introduced along with two other tilapia species to boost the indigenous tilapia stocks in Lake Victoria which had declined. The indigenous tilapia has since become extinct.
According to Dr Dismus Muhumuza, head of aquaculture research at NaFIRRI, the Nile perch was brought with four foreign tilapia species namely: Oreochromis niloticus, Tilapia zillii, Tilapia rendalli and Oreochromis leucostictes.
These species competed with the native tilapia species of Oreochromis variabilis and Oreochromis esculentus as the Nile perch hunted both of them with its biggest appetite directed at the nkejje.
Today figures from NaFIRRI show that Oreochromis variabilis is rare while Oreochromis esculentus is extinct.
The alteration of the native ecosystem had disruptive socioeconomic effects on local communities bordering the lake. Large-scale fishing operations, while earning millions of dollars from exports, have displaced many local people from their traditional occupations in the fishing trade and brought them to fishing villages where scarcity of fish has turned them into economic refugees.
On the flipside, Nile perch stimulated the establishment of large fishing companies and boosted sport fishing tourism in the region, with Murchison Falls considered one of the best fishing destinations in the world.
Every year, anglers from all over the world converge here to hook out Nile perch, weigh the fish and take their pictures with the catch, before releasing them back into the water.
But now, the tide has turned against the Nile perch, with man as its greatest enemy, threatening its existence and the livelihoods of the over 30 million people who depend on Lake Victoria.
"If this trend continues, more factories will have no choice but to close. There will simply be no fish left to sustain the factories," Muhumuza concludes.

BEACHGOERS, lifesaving clubs and councils are united in demanding answers over the mass death of marine life littering local beaches.

They have welcomed a decision by the State Government, in the face of mounting public concern, to set up a taskforce of scientists to investigate the mass fish kill.
But they warn the findings must be acted upon to quell community concerns of a repeat event.
Seacliff Surf Life Saving president Andrew Chandler said he was eager to learn the outcome of the investigation.
"We need to know if it is a natural phenomenon or caused by humans to show us that we are not doing anything wrong as a community, or if it does come from pollution then this is something we must address," he said.

Thousands of dead fish have washed up along the foreshore at Moana Beach.
TENS of thousands of small fish as well as snapper, whiting, kingfish and mulloway were found washed up in the sands between Brighton and Marino.

Thousands of dead fish have washed up along the foreshore at Moana Beach.
Henley Surf Life Saving Club president Neville Fielder said the spate of dead marine life was the worst in his 40 years at the beach.
"We had a lot of dead carp wash up on the shore a few years ago but that was nothing like this," Mr Fielder said.
Christies Beach Surf Life Saving Club president Ron Harwood said clubs urgently needed to know what was causing the fish to die.
"If it's a water issue we have to take whatever steps are necessary to keep people out of the water," Mr Harwood said.

Recfish SA executive director Gary Flack said the carnage of marine life along Adelaide's coast was unprecedented.
"The main concern is that is that they (the deaths) are ranging across a mix of species from shallow water fish like yellow fin whiting to reef dwellers like snapper," Mr Flack said.
Brighton Tackle and Fish owner Pete Whiting said an investigation by an independent body was needed to reassure the public the desalination plant was not to blame.
"The talk is all about the desal plant, it doesn't mean it is the desal plant but we need an independent inquiry," Mr Whiting said.

Holdfast Bay Mayor Ken Rollond said he wanted to learn whether pollution and run-off from creeks, rivers, and drains could be a cause of algal blooms.
"The investigation is a worthwhile thing, we need independent scientists," he said.
Onkaparinga Mayor Lorraine Rosenberg said it was crucial to find out if the cause was natural.
"We need to know whether it is natural or not, because if it's not then we have to look at what mechanisms can be done to prevent it," Ms Rosenberg said.

Onkaparinga councillor and former Surf Life Saving SA president Bill Jamieson said: "We need to work out what's happening with it because it's a pretty special gulf and a lot of unique species live down our way."
Biosecurity SA manager of aquatic pests Vic Neverauskas said the fact most of the dead fish were small, shallow-water species coupled with signs of irritated and swollen gills suggested an algal bloom was to blame.
Algal blooms, believed to be caused by a hotter-than-usual March, deplete oxygen in the water and cause fish to die.
Fisheries Minister Gail Gago said testing of fish and water samples would be completed as soon as possible.

"To date, pathology tests show no evidence of disease, with evidence so far tending to suggest the predominantly juvenile fish that have died have been subjected to heat stress or lower oxygen levels consistent with algal blooms," Ms Gago said.
"(However) all findings will be made public."
For more news on the south-west, pick up a copy of the Guardian Messenger, read our digital edition online, or become a fan of our Facebook page.

A taskforce will be appointed to investigate the mass death of fish and dolphins in South Australian waters.
Sixteen dead dolphins have washed up during the past month along with thousands of dead fish, two penguins and an unusual amount of sea grass.
The dolphins were were found between Maslins Beach and North Haven, with four on Kangaroo Island and one in the South East which may be unrelated to the other deaths.
The South Australian Museum's curator of mammals, Catherine Kemper, says most were less than 18 months old.
Marine experts are hoping autopsies on two dolphins could shed light on changing conditions in coastal waters.
Dr Kemper says a post mortem on one of the creatures revealed some organ damage but the results were inconclusive.
"There was E. coli identified near the blow hole of that animal and it didn't look one hundred per cent inside either so there was some evidence that something was going on in terms of pathology inside," she said.
"In other parts of the world, fish and dolphins have died as a result of biological toxins entering the system and these happen when you have things like red tides and algal blooms.
"We wouldn't normally do testing for this but we will this time."
The Government says the taskforce will be made up of a team of scientists from several departments.
State Greens MP Mark Parnell says it has not been properly funded.
"The Government needs to put some money into this. We need to know why these animals are dying, is it purely natural causes? Or is it, as most people suspect, something that we're doing?" he said.
"Whether it's pollution or whether it's climate change, whatever, we need to get to the bottom of it.
"Environmental emergencies need an emergency response and the government will need to find money so that the scientists can do their job properly. There's not much point bemoaning the death of sea life if you don't resource the scientists to find out what's going on."
Fisheries Minister Gail Gago says the taskforce is adequately resourced.
"Those payments are picked up by either [the Environment Department] or PIRSA and those funds are available from our existing resources to more than adequately cover those costs. So it's just irresponsible scaremongering," she said.
"We will continue the testing and seek to find out the underlying cause for that so at this point in time we simply do not know what's caused the dolphin and penguin deaths."
The deaths of dolphins are not the only unusual recent incident along Adelaide's beaches.
Several tonnes of seaweed piled up on Glenelg beach last week.
Days earlier, tens of thousands of dead leather jackets were discovered on beaches along Spencer Gulf and Gulf St Vincent.
The Environment Department said the fish deaths and seaweed piles could both have been caused by unusually high ocean temperatures.
Warmer waters produce large amounts of algae consuming the oxygen needed by the fish.
Follow 7News Adelaide on Twitter

The United Nations have sat up and taken notice of a young Australian's message - asking why our teenagers are being pressured to be too sexual too early.

A terrible loss Last week I covered a story about Karta the orangutan, who is recovering from losing her fifth baby.I was incredibly moved by her carers at the Adela...