Lyme Ticks Don’t Harm Mice

cary institute mouse taggingThe ticks that carry Lyme disease, black-legged ticks or deer ticks, do not appear to harm their white-footed mice hosts, a paper in press in the journal Ecology says. In fact, the research found, a larger tick load correlated with a longer life in male mice.

The mice are a reservoir for Lyme disease, a report on the study in Entomology Today notes. “Deer and other mammals can spread tick populations, [but] they do not carry the disease,” the report says. “Instead, ticks mainly pick up Lyme pathogens from white-footed mice.”

In a press release from the Cary Institute, paper co-author Shannon LaDeau, a disease ecologist at the Cary Institute, says, “From a human health perspective, the indifference that white-footed mice have to black-legged ticks…. signals a positive feedback loop that favors the proliferation of parasites.”

Lots of details in the Cary Institute press release, here.
And in the Entomology Today article, here.

Photo: The study drew on 16 years of white-footed mouse mark-and-recapture data collected at the Cary Institute of Ecosystem Studies in Millbrook, N.Y. Photo credit: Cary Institute of Ecosystem Studies/Sam Cillo.


What Do You Say to a Naked Moose?

Winter tick infestations in moose can become so severe that the moose rub the hair right off their bodies. These have been called “ghost moose,” because of the whiteness of the mooses’ bare bodies. The tick infestation can lead to death from: anemia, distraction from grazing, or exposure to cold.

Estimating winter tick populations is an important component of moose management.

Research in New Hampshire found that counting winter ticks by any of three different methods turned up similar results. Winter tick populations were monitored by:
-dragging a white sheet over low vegetation in the spring,
-counting ticks on hunter-killed moose at check-in stations in the fall, and
-noting hair loss patterns on moose in the spring.

The three methods all revealed a similar pattern of lower winter tick numbers in 2008 and 2009, with a spike in 2010.

You can read about the New Hampshire research in an article written for a general audience in New Hampshire Fish & Game’s magazine, Wildlife Journal.

Alces Journal published a paper that reached a similar conclusion. The research there was in Maine, however. Read the paper here.

Photo: Alan Briere, courtesy NH Fish & Game