A virus outbreak has killed 60,000 juvenile steelhead at Robertson Creek Hatchery and prompted the involvement of the Canadian Food Inspection Agency.
Fisheries and Oceans Canada has confirmed that there was an outbreak of Infectious Haematopoietic Necrosis (IHN) virus at the Robertson Creek Hatchery.
The virus was diagnosed in January after extensive laboratory testing, said Fisheries and Oceans Canada (DFO) spokesperson Carrie Mishima, who only responded to questions from the News by e-mail.
The virus has infected more than 60,000 juvenile steelhead at the hatchery, which have since been destroyed, officials said.
Hatchery staff became aware of the outbreak after noticing higher than normal mortalities in juvenile steelhead. Staff noticed signs of the virus and initiated lab tests.
According to the fisheries department, IHN is a naturally occurring pathogen in wild fish throughout the Pacific West Coast from Alaska to California.
IHN poses no risk to humans but it can spread quickly and has a 100 per cent mortality rate if a fish population becomes infected.
The virus is known to exist in Great Central Lake where the hatchery draws its water supplies. Lab tests identified the virus as the endemic, naturally occurring strain that is commonly found in Pacific sockeye.
The Canadian Food Inspection Agency was called because IHN is a reportable disease.
Staff have isolated the area where the infected fish were being held, and are cleaning and disinfecting the area.
Measures have also been put in place to control the movement of staff and fish in and out of the hatchery.
Cleanup will be completed when the CFIA is satisfied that the process has met their requirements.
The number of fish killed in the Vasse-Wonnerup Estuary this week has been revised to more than 10,000.
City of Busselton workers spent yesterday cleaning up the dead fish, mostly mullet, around the Vasse floodgate area.
The Department of Water says high levels of toxic algae are present in the waterway, which is likely to have caused the fish deaths.
The department says the oxygen levels, which were blamed for the fish kill of the same size last year, all appeared normal this time.
Findings of an independent review into the waterway’s management are set to be handed down this month.
Around P5.2-million worth of tilapia have been devastated as another fish kill hit anew portions of the critical Lake Sebu in South Cotabato in the last three weeks.
Rudy Muyco, Lake Sebu town’s lake warden, said Wednesday the continuing fish kill has already destroyed a total of 68.291 metric tons (MT) of fingerlings and adult tilapia from fish cages situated in the lake’s eastern and western section.
Citing the prevailing market prices, he valued the damage at P85 per kilo for the adult tilapia and P150 for the hybrid fingerlings.
As of Wednesday, he said the fish kill already affected around five hectares of fish cages and a total of 54 operators.
“The fish kill is still ongoing in some portions of the lake and the situation might get worse in the coming days due to the erratic weather condition,” he told MindaNews on the phone.
Muyco said the latest fish kill, which is the first this year, was caused anew by kamahong, a phenomenon that is mainly caused by the sudden rise in the water’s temperature.
He said several fish cage operators initially reported the problem in some portions of the lake last January 13 after the area’s weather condition suddenly changed due to a low pressure area that affected parts of Mindanao and Visayas.
Kamahong, which usually occurs during the rainy season, triggers the rise of sulfuric acid in the lake’s waters that eventually caused the massive fish kill, provincial fishery coordinator Rex Vargas earlier said.
“It occurs when cold rainwater, which is heavier than warm water, settles at the abyssal zone of the lake. This causes the upturn or upwelling of warm water carrying silts, sediments and gases such as hydrogen sulfide, ammonia, sulphur and methane gas produced by the decomposing organic matter such as fish feeds,” he explained.
Vargas said such situation results in the reduction of dissolved oxygen in the water, “forcing fishes to take in oxygen directly from the atmosphere and eventually die.”
In October last year, around 20 MT of harvestable tilapia and pangasius valued at around P1 million were devastated due to a fish kill that affected some 60 fish cages in the area.
In 2012, around 57 MT of tilapia were destroyed in two fish kills at the lake that were blamed on kamahong.
The initial fish kill in January 2012 ravaged some 48.55 MT of tilapia. It affected 48 fish-cage owners and left a total damage of P3.8 million based on tilapia’s market price of P80 per kilo.
In August that same year, an additional 8,000 kilograms of tilapia, valued at around P650,000, were destroyed in another fish kill that affected 14 fish cages at the lake.
Muyco said the municipal government is presently preparing for the scheduled dismantling starting next week of illegal fish cages along the lake as a strategy to prevent future fish kills.
“The lake is overcrowded. We need to significantly reduce the number of fish cages to its carrying capacity to resolve these problems,” he said.
Muyco said that based on their assessment, Lake Sebu currently hosts a total of 4,800 fish cages or around 1,800 more than its carrying capacity.
The municipal government of Lake Sebu and the provincial government of South Cotabato earlier issued a demolition order for all illegal fish cages at the lake.
Among the fish cages that were targeted for demolition were those that have no permits, sub-leased by their original owners and situated in the lake’s inlets and outlets.
Muyco said the two local governments earlier gave fish cage operators and owners until January 30 to demolish their illegal fish cages but it was extended to February 11.
“Around 65 fish cages have been so far demolished by their owners and this is continuing as we speak. By next week, we expect this number to reach around 1,000,” he added.
MAGNITUDE 3.5 – WEST YELLOWSTONE, MT
Subject To Change
Depth: 10 km
Distances: West Yellowstone, MT – 26 km (16 miles) ENE (69 degrees)
Gardiner, MT – 33 km (21 miles) S (191 degrees)
Island Park, ID – 51 km (32 miles) ENE (57 degrees)
Big Sky, MT – 71 km (44 miles) SE (146 degrees)
Salt Lake City, UT – 453 km (281 miles) N (11 degrees)
Why have a significant number of dead albatross washed up on Ripiro Beach?
Regular beach patroller Noel Hilliam says he saw 12 dead albatross washed up along about five kilometres of beach south of Glinks gully about two weeks ago.
“I’ve never seen anything like this before. You sometimes see the odd one but never this.”
He says the birds appeared to have been dead for some time and were “looking pretty battered.”
“I’d like to know what caused it. Was it starvation, something they ate or a big storm?”
Mr Hilliam contacted the Department of Conservation but had not heard back from them at the time of print.
A live but exhausted southern royal albatross was found on the beach in mid January and taken to the Whangarei Native Bird Recovery Centre where, despite initially improving, it died.
Co-owner of the Whangarei Native Bird Recovery Centre, Robert Webb says he is concerned to learn there has been so many dead birds on the west coast beach.
“We usually hear about a few birds, but not as many as this. I am very concerned their deaths may not be due to stormy weather which is the normal cause.
Mr Webb said these ocean flying birds can fall victim to exhaustion from struggling with extreme off shore weather conditions.
He is also worried the birds have been left on the beach.
“An autopsy should be performed on one of these birds, to confirm the cause of death. The birds should also be removed and checked for identity bands and then buried,” said Mr Webb.
From the photograph sent to him by the Dargaville and Districts News he believes the bird to be a wandering albatross, but says it is difficult to be absolutely sure because of the bird’s condition.
“‘We have had four wandering albatross at the recovery centre on the last few years that had been banded.
“One in Florida, two during Antarctica expeditions and one from the Bismark Islands.”
Information on their recovery is sent to the country of origin.
Two new suspected bird flu cases were reported in South Korea Saturday, stoking concerns that the highly pathogenic poultry disease may be spreading in the country, the agriculture ministry said.
According to the ministry, the additional suspected cases were reported at a chicken farm in the southern port city of Busan, and a duck farm in Jincheon, 90 kilometers south of Seoul.
A virulent H5N8 strain of avian influenza has so far been confirmed in 27 cases in South Korea since it was first detected on Jan. 16 in Gochang, 300 kilometers south of Seoul.
More than 2.4 million chickens and ducks have so far been culled.
The government has pointed to migratory birds as the original source of bird flu after the H5N8 virus was identified in a group of wild ducks found dead Jan. 17 at a reservoir near a duck farm that reported the first outbreak of AI. The highly pathogenic strain of bird flu has since been identified in 13 other cases that involved wild birds.
Health officials said the H5N8 strain, unlike a few other strains of bird flu, poses no immediate threats to humans. No human infection of the strain has been reported, they said.
National water agency PUB said that it was notified about the dead fish on Tuesday morning, and immediately sent contractors to clean up the river. The clean-up was completed by 3pm on Wednesday, the spokesman added.
PUB explained that lower levels of dissolved oxygen in the water caused by recent hot and dry weather could have killed the fish. It said that only two species of fish – tilapia and mayan cichlids – were found dead.
At least 1,122 carcasses of Olive Ridley turtles were washed ashore on the beaches of Tamil Nadu and Andhra Pradesh in January alone.
More than 145 dead turtles were found on the stretch between Marina Beach and Neelankarai, while 226 were found between Neelankarai and Marakkanam. In Andhra Pradesh, Nellore recorded 547 carcasses. Marine conservationists say there has been a sharp increase in the number of dead turtles found along the beaches of Tamil Nadu and Andhra Pradesh.
The main problem, according to marine experts, is fishing nets. The turtles normally come to nest on beaches on the east coast from January to March. “The female turtles dig nests and lay around 60 to 120 eggs at a time. The same turtles may nest two or three times and stay close to the shore during this time. As they stay close to the shore, many easily get entangled in the fishing nets,” said Supraja Dharini, chairperson of TREE Foundation, a non-governmental organization that works for the protection of endangered marine species. The foundation conducted the study of the beaches.
Dharini said not a single day passed in January without phone calls from volunteers about carcasses on beaches. “The main reason for this tragedy is that the turtles get caught in the trawl fishing nets of mechanised boats, gill nets or ray fishing nets. Turtles need to come to the surface of the sea to breathe. Once they are trapped in the net, they remain underwater and drown,” said Dharini.
Marine expert P Dhandapani said the injuries on the carcasses had to be investigated. “In many cases, turtles die after getting entangled in fishing nets. Since the rate of mortality is so high in this case, the injuries on the carcasses need to be investigated properly before reaching a conclusion,” said Dhandapani, retired marine scientist, Zoological Survey of India.
Scientists estimate that only one in 1,000 hatchlings survives to adulthood. Creating awareness, according to Dhandapani, is not enough. “Everyone knows that many turtles die after getting trapped in fishing nets. But how do we stop this? The government must implement the suggestions made by marine scientists such as banning some types of fishing nets to prevent such deaths,” he said.