Epizootic Hemorrhagic Disease (EHD) has been confirmed as the cause of death in over 100 deer in southwestern Oregon, the Oregon Department of Fish and Wildlife announced last week. EHD had not been observed in this region of the state before. The finding was confirmed by Oregon State University’s Veterinary Diagnostic Lab.
EHD is transmitted by gnats and causes disease in both deer and livestock. In this case, the diseased deer were black-tailed deer.
There have also been reports of more than 200 dead deer in two counties that are south of the EHD site, the press release says, but those deer where shown to have Adenovirus Hemorrhagic Disease (AHD), which is common in the area and spread through nose to nose contact.
Late 2012 saw first case of chronic wasting disease (CWD) in captive deer in Iowa, and there has been chronic wasting disease in wild deer in every state bordering Iowa, but Iowa only recorded its first case of CWD in a wild deer in the state in an announcement on April 9.
According to an Iowa Department of Natural Resources press release, “The deer was reported as harvested in Allamakee County during the first shotgun season in early December.”
The state is formulating a response plan and coordinating efforts with nearby Minnesota and Wisconsin.
A report by KTVO says that the gates of the hunting facility in Davis County where the first case of CWD was found two years ago were chained open when the facility was supposed to be quarantined to protect local deer from the disease.
Plants, including crop plants such as alfalfa and tomatoes, may serve as a reservoir for the prions, or misfolded proteins, that cause chronic wasting disease in deer (as well as other prion diseases such as scrapie in sheep, and mad cow disease), reports WisconsinWatch after a careful reading of the The Wildlife Society conference program.
WisconsinWatch is produced by the Wisconsin Center for Investigative Journalism. And they certainly investigated here.
Christopher Johnson, U.S. Geological Survey’s National Wildlife Health Center will present a talk on his research at the conference on October 7.
Oh, and Johnson found that the prions from plants were infectious when injected into mice.
I’m going to skip right over the scary prospect of plants as a reservoir for prion diseases and go right to the next point made in the WisconsinWatch article: this finding is not going to change the fact that the Wisconsin Department of Natural Resources has pretty much given up on managing CWD in the state.
Johnson’s findings have not yet been published in a scientific journal, and it appears that the National Wildlife Health Center has not yet released a report or a press release on the research.
It’s been a quiet summer for epizootic hemorrhagic disease (EHD) in deer. Either conditions didn’t favor the biting midges that spread the disease among deer, or the northern states that experience periodic fatal outbreaks of the disease are becoming used to the new normal.
EHD season isn’t over, though, as these two news items show. Reuters says that wildlife managers in Montana are trying to pin down the cause of death for 100 white-tailed deer along the Clark Fork River. EHD had not been previously found in Montana west of the Continental Divide, the article says.
In North Dakota, there is no doubt that EHD is the cause of deer deaths there. An Associated Press story says that North Dakota’s Game and Fish Department has suspended the sale of 1,000 doe hunting licenses because of an EHD outbreak that began in August and continues, the article quotes ND wildlife Chief Randy Kreil as saying.
Two stories today focus on two different states’ efforts to get lead out of the environment.
An article in the Portland (Maine) Herald Press literally goes behind the scenes of the recent legislative ban on lead fishing gear in Maine, which was passed earlier this year, but won’t totally ban the lead gear until 2017. It goes into the lab of Mark Pokras, a Tufts University professor of wildlife health, who played a role in encouraging that legislation. Pokras has been studying lead poisoning in loons for over 20 years.
Pokras says that lead poisoning is responsible for the deaths of over a third of the loons that find their way to his lab in Massachusetts.
In Minnesota, studies show that a bad shot with a lead bullet (such as one that hits a hip bone), can cause lead to splinter throughout a white tailed deer’s flesh to the extent that it would be difficult, or impossible, to remove all of it. For the sake of public health, and also for the sake of the state’s bald eagles, the Minnesota Department of Natural Resources encourages deer hunters to voluntarily use copper bullets.
The article details some of the differences between hunting with copper and lead bullets, which implies that a different technique may be more effective when using copper bullets.
California Department of Fish and Wildlife (CDFW) researchers have captured and collected hair and blood samples from more than 600 deer and elk in an effort to understand “deer hair-loss syndrome,” says a CDFW news release.
A non-native louse appears to be a key factor in the syndrome, which also sometimes includes internal parasites. Deer with the syndrome are skinny, and the fawns don’t survive. A report from Fox 40 in Sacramento notes that the syndrome has been known in Oregon for years.
“Some of us speculate that the louse-infested deer spend so much time grooming they become easy targets of predation by coyotes or mountain lions,” said CDFW senior wildlife biologist, Greg Gerstenberg in the release.
The researchers have counted and identified lice on the captured deer, are following them through radio collars, and have treated some for lice. They hope to have answers soon.
“Hunter harvest continues to be the greatest cause of death of both adult and yearling bucks, while predation was the leading cause of fawn mortality, with most predations occurring within the first four to six weeks following birth,” said Jared Duquette, research scientist with the Wisconsin Department of Natural Resources and lead researcher for a five-year study of causes of adult deer mortality and a three-year study of fawn mortality in an item in department’s weekly news bulletin.
Capture of adults will continue through the 2012-13 and 2013-14 winters. Fawns were live-captured in May and June in 2011 and 2012 and will be captured again in 2013. A number of captured adults and fawns are fitted with radio collars. All are fitted with ear tags. Additional metrics are collected including body weight and size, blood samples, sex, presence of external parasites and age. Does are also examined for pregnancy. Deer are followed by radio signal until death, at which time researchers study the mortality to determine cause.
More details on the two studies are available in the department’s news report. Wisconsin is also conducting some other interesting deer studies. You can see the list here. I’d be interested to know the results of “An evaluation of the usefulness of deer-vehicle collision data as indices to deer population abundance.”
The Pennsylvania Department of Agriculture announced the first case of Chronic Wasting Disease (CWD) in deer there last week. As you may guess from the state department issuing the news, CWD was found in captive deer.
CWD had been found in New York, which borders Pennsylvania, several years ago and is believed to be eradicated there. But there have been more recent incidents in West Virginia and Maryland, which also border the state.
(My rough measurements show the Pennsylvania case as being about 40 miles from where CWD was found in Maryland and West Virginia.)
In other deer health news, Louisiana State Wildlife Division chief Kenny Ribbeck told the Louisiana Wildlife and Fisheries Commission last week that Hurricane Isaac killed up to 90 percent of the deer fawns in the Maurepas Basin, according to an Associated Press article that you can read in The Oregonian. Deer hunting in the region has been adjusted as a result.
And in the category of “when is no news actually news” the Canadian Cooperative Wildlife Health Centre notes in its blog that epizootic hemorrhagic disease (EHD) came awfully close to Canada this year. The midge that spreads EHD is not found in Canada, it says, but the disease may move north with the midge because of climate change. It also notes that because the disease has never struck there, the outbreak may be severe.
By using blood samples from hunter check-ins, the lab is able to get information from remote areas that are difficult (and expensive) to monitor through traditional methods. And, according to the WSCH story, they are finding a surprising amount of these diseases out there.
In Nebraska, the state veterinarian is saying that cattle in the state are getting EHD, which again is considered to be a rare occurrence. He is seeking more information from cattle owners whose animals are experiencing EHD symptoms (which are virtually identical to bluetongue symptoms, which is common in cattle). Read the press release here.
Finally, in Texas, officials had set up a containment zone when chronic wasting disease (CWD) was detected in deer on the border with New Mexico. However, the latest news from the San Angelo Standard-Times says that the new rules will be delayed until the Texas Parks and Wildlife Commission on November 7-8. According to the Austin Statesman, that’s after the archery season and a few days after the start of the standard deer season.