WDFW working to unravel deer disease mystery

OLYMPIA— In an effort to determine the cause of a disease weakening young blacktail deer on the westside of the state, the Washington Department of Fish and Wildlife has transported eight deer to Washington State University for observation and testing.

For the past two years, the Department has been working with several university laboratories specializing in wildlife disease to try to determine the cause of the problem, which causes deer to lose hair, leaving them vulnerable to weather and exhaustion. The actual hair loss is likely caused by high numbers of deer lice. Typically, lice numbers increase on wild animals when their immune systems are suppressed for some reason. It is hoped that by sending both healthy and affected deer to WSU, animal scientists there may be able to determine the source of the immune suppression.

The most-recent testing effort involves five deer which show signs of the condition and several from unaffected herds who show no symptoms. The deer are being penned for the study to avoid spreading the disease to wild deer on the eastside of the state.

The hair-loss syndrome, which first surfaced in the spring of 1997, now affects deer in many areas of western Washington, In early stages, the syndrome causes whitish to yellow discolorations of hair over rib cage, flanks, rump and neck; with hair loss occurring in those areas as the condition worsens. Affected deer are often seen to lick and groom obsessively. Excessive hair loss during cold spring rains subjects deer to severe stress, resulting in nutritional exhaustion or hypothermia. Safari Club International, a hunting organization, has donated radio collars to help WDFW monitor deer suffering from the syndrome. Preliminary monitoring results indicate that affected fawns and yearlings are more likely to die from the effects of the hair loss syndrome, while many affected adult deer appear to recover.

Tests performed at WSU, Oregon State University and the University of Georgia have shown no viral or bacterial cause for the syndrome.