A species of exotic deer lice that is significantly impacting California black-tailed and mule deer populations, is also being seen in Nevada mule deer.  Infestation of the exotic lice leads to significant hair loss in deer populations.

 

To gain more information about how the Nevada mule deer are being impacted,  NOU spoke with Nevada Department of Wildlife veterinerian, Ms. Peri Wolff.

 

Ms. Wolff advised that In Nevada, documented cases of exotic lice infestations in mule deer have been reported across the state, including western, middle and eastern regions.

 

Although Nevada is not currently seeing a widespread problem with infestations at this time, California is seeing a large spike in mule deer mortality believed to be related to the lice.  Ms. Wolff stated that the hair loss/ lice infestations in deer populations have been a problem since the 1940’s, not only in California, but in numerous western states.

 

The exotic lice species is not the same species as the North American deer lice Ms. Wolff advised.  The North American deer lice typically number only one or two dozen per deer, whereas the exotic lice will be number in the “thousands” per deer, according to Ms. Wolff.

 

Because of the extreme infestation, the deer continually scratch, bite and chew at their hides, causing the extreme hair loss.  Ms. Wolff states that the mortality of the deer population due to the lice infestation is not completely understood.

 

Researchers have theorized that when the deer become lice infested, their continual grooming patterns become a distraction, making the deer more vulnerable to predator attacks.  Others speculate that significant hair loss in the deer creates a problem in extremely cold temperatures, making it harder for the deer to conserve energy (Source: Reno Gazette Journal).  Not surprisingly, fawns are dramatically impacted and vulnerable when infested.

 

Interestingly, the exotic louse species originates back to non-native fallow deer, which were  introduced to North America dating back to the colonial era.  “George Washington had fallow deer” commented Ms. Wolff.

 

How the exotic louse crossed species to the mule deer is unknown, however hair loss in black-tailed deer populations were documented back in 1996, when infested deer were found  in Oregon and Washington (Source: San Francisco Chronicle).

 

We asked Ms. Wolff why Nevada is not seeing the mortality and impact on mule deer vs. those in California.  She believes that because our overall mule deer population density is low, the infestation risk is less, as greater density leads to more crowding of herds and increased transmission of the lice.

 

However, she states that Nevada mule deer hunters be on the look-out for possible exotic louse infestations while out in the field.  Besides hair loss, look for deer infested with huge numbers of lice, typically concentrated heavily in  the armpits and groin area.

 

Ms. Wolff asked that  Nevada hunters please report to NDOW any possible observations so Nevada wildlife officials so they can keep apprised of the situation here in our state.

 

Peri Wolff has been an NDOW veterinarian for the past 4 years;

 thank you Ms. Wolff for keeping NOU members updated!