November 3, 2011

Today's Wildlife Disease News Stories


Fish & Game cautiously optimistic about fish disease

MAF has informed Otago Fish & Game that the hatchery trout infected with the Aeromonas bacteria is not the ‘typical’ strain of the disease. “The ‘typical’ version of the bacteria is of most concern to hatchery and fish-rearing facilities so it’s encouraging that this has been ruled out,” says Otago Fish & Game chief executive Niall Watson. MAF has advised Fish & Game that further testing is needed to prove whether it is the more common ‘atypical’ variant.

While Mr. Watson and his staff are still very concerned about any disease affecting trout, he says at this stage the latest development appears to be encouraging.

“We understand that if further tests return a positive for the ‘atypical’ strain, then this is less virulent in trout. We welcome the news from MAF and await further laboratory results. We’ll also be considering the implications of this development over the next few days. At this stage, though, it appears to be positive news.” Mr. Watson says there have been no further fish mortalities at the Macraes hatchery and stock held there all appear to be in a healthy condition.

“We are continuing to monitor the situation closely. Since the discovery of the disease we’ve enforced strict hygiene controls on-site and have a self-imposed restriction on further fish releases. We will review the situation in mid-November and make a decision then on whether or not to recommence releases from the hatchery.” Mr. Watson says there have been no reports of infected trout from waterways where releases were made before the discovery of the infected hatchery fish.

Scoop -
2 Nov 2011
Location: Otago, New Zealand


Mussel-bound lakes could imperil birds

Birds can be put on the list of possible victims of the zebra mussels being found in Minnesota lakes.

… While filtering the water, the mussels accumulate toxins, pollutants and microorganisms. Those concentrations are intensified in the bodies of the fish that eat them. The fish either die and wash ashore or become paralyzed and float to the surface. Birds eating those fish can die.

Next comes botulism poisoning.

"Zebra mussels have a connection with avian botulism," said Carrol Henderson, superintendent of non-game wildlife for the DNR. Botulism is a byproduct of mussel waste. The waste is eaten by fish, which then can infect fish-eating birds.

Star Tribune -
1 Nov 2011


Reported Wildlife Mortality Events to the USGS National Wildlife Health Center Updated

USGS and a network of partners across the country work on documenting wildlife mortality events in order to provide timely and accurate information on locations, species and causes of death.

This information was updated on Oct 24, 2011 on the USGS National Wildlife Health Center web page, New and Ongoing Wildlife Mortality Events Nationwide.

Quarterly Mortality Reports are also available from this page. These reports go back to 1995.

USGS National Wildlife Health Center
24 Oct 2011

Photo courtesy of The Guardian's Week in Wildlife